tag:blogger.com,1999:blog-81605492795449064252024-02-19T03:35:28.785-08:00The Birds and the BeesEverything you were afraid to ask about the secret lives of animals.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.comBlogger17125tag:blogger.com,1999:blog-8160549279544906425.post-89424977271949772012011-03-22T17:02:00.000-07:002011-03-22T18:16:57.746-07:00For Sea Turtles, Feeling Excluded is a Good Thing!<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEia_GRD5q2RpIzg9bhz-d9X0-Cfmsi_XxP8r7QEVS2SIaqGMouwdqPov8D1pJ5_EejvH_CwjqO59EAul0fjVh7M_ErpQhKvZJS_bGK2f0Vz8aYOx9buBA8UBiDeZM1uDWNbdfkDGwXFUvo/s1600/sea-turtle-01-138471299093246DzK.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEia_GRD5q2RpIzg9bhz-d9X0-Cfmsi_XxP8r7QEVS2SIaqGMouwdqPov8D1pJ5_EejvH_CwjqO59EAul0fjVh7M_ErpQhKvZJS_bGK2f0Vz8aYOx9buBA8UBiDeZM1uDWNbdfkDGwXFUvo/s320/sea-turtle-01-138471299093246DzK.jpg" width="320" /></a></div>Life as a sea turtle can be rough. Not only do you sometimes have to migrate hundreds to thousands of miles to reproduce, sometimes you get caught in commercial fishing nets and drown. Ungh.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0801880076&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Hopefully your good friend TED will help you out with that. Not Ted Nugent. While I am sure sea turtles like "Cat Scratch Fever" as much as the next species, when they find themselves swept up in a fishing net, they can escape through a Turtle Excluder Device. Oh, <i>that</i> TED!<br />
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As <a href="http://scientistatwork.blogs.nytimes.com/author/lekelia-d-jenkins/">Lekelia Jenkins</a> writes in today's New York Times <a href="http://scientistatwork.blogs.nytimes.com/2011/03/22/how-to-not-catch-a-sea-turtle/"><i>Scientist at Work</i></a> blog, a Turtle Excluder solves what would seem like an insurmountable problem: creating a hole in the net big enough for a huge turtle to pass through but that prevents the escape of smaller critters like shrimp. The solution is actually quite simple: cover the hole with a trapdoor flap of netting that can only be opened by something heavy (like a sea turtle) but not something small (like fish or shrimp). Check it out:<br />
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Happy World Water Day!<br />
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In other news, Knut, arguably the world's most famous polar bear, <a href="http://www.time.com/time/world/article/0,8599,2060743,00.html?hpt=T2">died today at the age of four</a>. He became famous as a cub because his mother rejected him and he was successfully hand-reared by a human. Among his accomplishments: sharing the cover of Vanity Fair with Leo DiCaprio. RIP Cute Knut.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-8573791616011377052011-03-19T16:18:00.000-07:002011-03-19T16:18:07.284-07:00Female Promiscuity: Darwin's Benefit of the Doubt<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidV0UDy8VoeR9EXXEl-GcEZOGdrZHq4n1QMeXlvRszqTXxYYDBad47hIJOQk1i3M39aEVOZedX_OM1rJWmK1J6Ao3hPApeDupCPF-Q2AezJ4IoVAk_7NFnsDzURiYta-Gx1RQAVlsxR0M/s1600/296-12766001755MN5.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="214" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidV0UDy8VoeR9EXXEl-GcEZOGdrZHq4n1QMeXlvRszqTXxYYDBad47hIJOQk1i3M39aEVOZedX_OM1rJWmK1J6Ao3hPApeDupCPF-Q2AezJ4IoVAk_7NFnsDzURiYta-Gx1RQAVlsxR0M/s320/296-12766001755MN5.jpg" width="320" /></a></div>If you have been following this blog, female philandering in various animal species should come as no surprise to you. (If you have not been reading along but are interested, check <a href="http://bird-n-bee.blogspot.com/2011/02/why-do-females-sleep-around-geometry-of.html">this</a> out. Or <a href="http://bird-n-bee.blogspot.com/2011/02/monogamy-can-be-stressful.html">this</a>.) <br />
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However, a new book by scientist and author Tim Birkhead illustrates how the greatest naturalist of all time got it wrong. And how generations of scientists also got it wrong as a result.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=1596915412&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>In his book, <i>The Wisdom of Birds: An Illustrated History of Ornithology</i>, Dr. Birkhead discusses one of the biggest misconceptions in the study of animal behavior: that female songbirds are sexually monogamous. Most songbird species are socially monogamous, forming pair bonds in which one male and one female cooperate to raise offspring. But it wasn't until the last decade or so that we could determine with DNA fingerprinting that the male in the pair is not always (quite often not!) the genetic father of the chicks in the nest. <br />
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Mommy's babies are daddy's maybes.<br />
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So perhaps Charles Darwin can be forgiven for assuming that social monogamy is the same thing as sexual monogamy among songbirds when he wrote <i>The Descent of Man, and Selection in Relation to Sex</i>. After all, Mr. Darwin knew nothing of DNA or genes. Despite being a contemporary of Gregor Mendel, he missed the boat on the principles of inheritance we take for granted today.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0814720641&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Dr. Birkhead argues that Mr. Darwin should have known better. After all, he observed it himself! Darwin, like many gentlemen of his day, was a breeder of doves and therefore surely observed the occasional dalliance by pair-bonded females. He knew about female promiscuity among thief pigeons - in which females were known to abandon a mate in favor of setting up shop with a sexier male. <br />
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Dr. Birkhead discusses additional examples of female promiscuity described by Mr. Darwin and then addresses the question: Why, in the face of evidence to the contrary, did Darwin conclude that only males were evolving promiscuity under sexual selection?<br />
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Interestingly, it may have been due to his Victorian sensibilities: it was simply impolite to discuss such a scandalous notion as female philandering. To compound matters, his daughter was his editorial assistant and he may have been uncomfortable sharing such conclusions with her.<br />
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Whatever Darwin's reasons, Dr. Birkhead argues that generations of scientists - including such ornithological heavyweights as David Lack - went on to largely dismiss female promiscuity in birds because Mr. Darwin said it was unimportant!<br />
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I teach a course on Evolutionary Biology every academic year. One of the first lessons in the class is that uncritical acceptance of any theory or idea is bad practice for a scientist. That even though I consider Mr. Darwin's theories about natural and sexual selection to be powerful and well-tested ideas, as a scientist I must be among the most skeptical of them.<br />
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Dr. Birkhead's book is an excellent splash of cold water in the faces of uncritical scientists. I believe it will make an excellent addition to my course reading list.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com1tag:blogger.com,1999:blog-8160549279544906425.post-19185864453997062352011-03-17T18:04:00.000-07:002011-03-17T18:04:42.134-07:00What is the most common predator in North America? Thufferin' Thuccotash!<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhqZJ-cclhloQ7jz4imhj3UGV4MS6QMFZIfMJQFknt3lPLX9WBSuMRtUnLajV6JeovuwW1TJUyNpyenimprKVSMRSkU01-F5g5qq8wKGofM8mHcTFvOBu3_CBUjLxwxawzwEMhtFkJqEV0/s1600/black-and-white-cat.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="228" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhqZJ-cclhloQ7jz4imhj3UGV4MS6QMFZIfMJQFknt3lPLX9WBSuMRtUnLajV6JeovuwW1TJUyNpyenimprKVSMRSkU01-F5g5qq8wKGofM8mHcTFvOBu3_CBUjLxwxawzwEMhtFkJqEV0/s320/black-and-white-cat.jpg" width="320" /></a></div>If I was a contestant on Jeopardy, I probably would have guessed "What is <i>Homo sapiens</i>?" <br />
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But as <a href="http://blog.nwf.org/wildlifepromise/2011/03/new-studies-highlight-impact-of-outdoor-cats-on-birds-and-other-wildlife/">Laura Tangley reports in her blog</a>, The Wildlife Society announced on Tuesday that the domestic cat, <i>Felis catus</i>, is the most bloodthirsty of killers these days. It seems there as many as 157 million cats running loose in the United States.<br />
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Wait. Read that again: 157 million cats running loose!<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0226647277&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Maybe it is because they do not compete with us for the kind of prey found at Dunkin' Donuts that most of us have failed to notice the body count these legions of carnivores have racked up. According to <a href="http://joomla.wildlife.org/index.php?option=com_content&task=view&id=845&Itemid=183">The Wildlife Society</a>, they are racking one up to the tune of one million birds per day and up to a billion birds per year.<br />
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Assuming there are four and twenty blackbirds baked in a pie that adds up to about 41,666,666.66 sixpence per year. Quite the butcher's bill. <br />
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Folks, one-third of the birds in North America are threatened or endangered. Keep kitty inside.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com1tag:blogger.com,1999:blog-8160549279544906425.post-84392703316779082062011-03-11T05:27:00.000-08:002011-03-11T10:41:21.755-08:00Why do they eat poop? The answer might save your life!<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh_X0MrtA9emyebmsovE9y656K2uVUyIwjGI6qFtRRNnpj-W_HH9j18UVTxJ-VdbIJxqGYe9NeavZ402AypcGQNZ-mzSPlUZu2tVuSfamNhJWa7CLc94TAC6c8_BmGM56YQ_0zjX-hxoPw/s1600/1-1222003159fAx6.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh_X0MrtA9emyebmsovE9y656K2uVUyIwjGI6qFtRRNnpj-W_HH9j18UVTxJ-VdbIJxqGYe9NeavZ402AypcGQNZ-mzSPlUZu2tVuSfamNhJWa7CLc94TAC6c8_BmGM56YQ_0zjX-hxoPw/s320/1-1222003159fAx6.jpg" width="320" /></a></div><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0142409308&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Anyone who has ever kept a pet rabbit has seen Mister Hoppypants gobble up feces like it was Cocoa Puffs. Bunnies like poop! So do hamsters, guinea pigs, and koalas. Gorillas, elephants, hippopotamus. Puppies. Terrestrial isopods. Chimpanzees. The list goes on and on. Animals have a culinary craving for kaka!<br />
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Assuming that you do not occasionally sample your own stool, news of this phenomenon may be somewhat hard to swallow. (ba-dum-bump) There are, however, a number of good reasons why it makes biological sense.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0754641163&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>For herbivores that (lacking the enzyme to break down plant cell walls) are unable to completely digest food the first time around, re-eating food as feces gives the digestive system more time to break it down. It may also help the animal reclaim limiting vitamins and nutrients. It might remove cues that a predator could use to find the pooper.<br />
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Or, as Nicola Jones writes for Nature.com, eating fecal material might prevent pathogens from killing you.<br />
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According to a study presented by Brett Finlay (University of British Columbia) at the International Human Microbiome Conference, mice that ingested particular kinds of poo were far more likely to survive exposure to gut pathogenic bacteria. The experimental design was straightforward: one strain of mice was resistant and a second strain susceptible to <i>Citrobacter rodentium</i> (the pathogenic bacterium). Dr. Finlay killed all the bacteria in the susceptible mice with antibiotics and then fed them feces from resistant mice. The resistance was thereby transferred and most of the recipients survived. The key appears to be that other bacteria living in the guts of resistant mice prevent the pathogen from doing damage.<br />
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While this approach is new, it nonetheless may not come as much surprise to the medical community. After all, they have been performing fecal transfusions for years.<br />
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What? You've never had a fecal transfusion?<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=192913214X&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>For some forms of colitis, medical practitioners will administer enemas of gut bacteria from the feces of close relatives to the patient. A 2003 study published in the journal <i>Clinical Infectious Diseases</i> by Johannes Aas and colleagues found that most patients treated with donor stool survived diarrhea and colitis associated with the bacterium <i>Clostridium difficile</i>. They further reported that "no adverse effects associated with stool treatment were observed."<br />
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That's good, because just reading about how the enemas were prepared using household blenders and coffee filters had an adverse effect on me.<br />
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And I think I will skip that bowl of Cocoa Puffs this morning.<br />
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To read more, visit <a href="http://blogs.nature.com/news/thegreatbeyond/2011/03/for_mice_swapping_fecal_bacter.html">Nature.com</a>:<br />
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<a href="http://blogs.nature.com/cgi-bin/mt/mt-tb.cgi/12950">http://blogs.nature.com/cgi-bin/mt/mt-tb.cgi/12950</a>Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-73867238158937652662011-03-09T13:49:00.000-08:002011-03-09T14:00:29.319-08:00Why don't humans have spines on their penises? Ask a chimpanzee!<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjm2zl1Nyr4e3iPPl4e5HRk3g00php0CuBPhP48A2nNsRGnb_7FTc_sCdydLZk0dqTuaLZSfX7U3uIx0I_mt5xGvtzWolBWGwI3hRZB00q-M5MhwZo78ONlaClJ-Eow5pmcKoDirRVu_1g/s1600/chimpanzees.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjm2zl1Nyr4e3iPPl4e5HRk3g00php0CuBPhP48A2nNsRGnb_7FTc_sCdydLZk0dqTuaLZSfX7U3uIx0I_mt5xGvtzWolBWGwI3hRZB00q-M5MhwZo78ONlaClJ-Eow5pmcKoDirRVu_1g/s320/chimpanzees.jpg" width="240" /></a></div>Yes, you read the title correctly. Other primates have spiny penises, including our closest cousins. The question is: why don't we?<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0060984031&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Several theories have been proposed to account for penis spines in those species that have them. It is possible (as with the <a href="http://bird-n-bee.blogspot.com/2011/03/earwig-genitals-size-really-does-matter.html">earwigs I wrote about recently</a>) that penis spines serve to remove sperm left by other suitors that previously copulated with a female. Another theory is that the spines injure the female during copulation, ensuring that she will not be in the mood for sex again for a while - long enough, at least, that competitor sperm arrives too late.<br />
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Whatever the reason spines grow from the penises of other species, they decidedly do <b>not</b> grow there in humans. No doubt this comes as quite a relief to many of my female readers.<br />
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We may not know exactly <i>why</i> our species dropped this peculiar prickly penile adaptation, but thanks to the work of McLean and colleagues at Stanford University (published today in <a href="http://www.nature.com/news/2011/110309/full/news.2011.148.html">Nature</a>) we know <i>how</i> we dropped it. We lost some of our DNA.<br />
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McLean and colleagues (including Gill Bejerano and David Kingsley) used a novel - and very clever - method of analyzing the DNA of chimpanzees and humans. Rather than looking for similarities (as many studies do), McLean <i>et al</i>. looked at the <i>differences</i>. They found more than 500 regions present in the chimpanzee genome that is missing in humans.<br />
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One of the sequences missing in humans is located near the Androgen Receptor gene in chimpanzees. When the sequence was inserted into mice, embryos developed penis spines. They also developed sensory whiskers - another trait that our ancestors dropped sometime after we shared a common ancestor with chimpanzees.<br />
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The missing sequence in humans appears to be a developmental switch: something that turns on genes for particular traits (such as spines or whiskers). Lose the switch, lose the trait.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0312046707&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>The correlation between these two traits is interesting: Perhaps we lost our whiskers because of selection against penis spines? Or did we lose our penis spines because of selection against whiskers? Some have argued that loss of penis spines accompanied our foray into monogamy. I have always been suspicious of this theory, though, because human cultures are not all socially monogamous and there is plenty of philandering in those that are.<br />
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As much as we men like to think everything revolves around our genitals, perhaps it revolves more around our whiskers! (or lack thereof)Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-50730198434027597082011-03-08T16:10:00.000-08:002011-03-08T16:10:24.851-08:0060 year old albatross hatches chick. Talk about stamina!<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg7GCA23nMA44yYoMaVbMQb1ckUZVDis0MA4UhmWgOXBj-LvtprG-QN95J9LP87cRb9MTq4dZXAGPMpkdTX9-caAGGUqh8B1kaIA_ngxFuffxBBhwGLSaRsU0STeTYMsaaWl8CMPFAKc78/s1600/1299613391725.JPEG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="223" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg7GCA23nMA44yYoMaVbMQb1ckUZVDis0MA4UhmWgOXBj-LvtprG-QN95J9LP87cRb9MTq4dZXAGPMpkdTX9-caAGGUqh8B1kaIA_ngxFuffxBBhwGLSaRsU0STeTYMsaaWl8CMPFAKc78/s320/1299613391725.JPEG" width="320" /></a></div><div style="text-align: center;">Photo Credit: John Klavitter, U.S. Fish & Wildlife Service</div><br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0691131325&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Her name is Wisdom and she certainly knows something about life. Not only is Wisdom the oldest wild bird in North America, she's also perhaps the oldest mother. At sixty years of age, Wisdom successfully hatched a chick, according to the US Fish and Wildlife Service.<br />
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And this is hardly an anomaly. She is known to have successfully reproduced for at least the last several years and has more than 30 chicks under her belt total.<br />
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To put this in perspective, elephants can live up to 70 years (the oldest I am aware of died at age 82) and giant tortoises around 100 (although some have been reported to break 175). Other Methuselah species include sturgeon (100+ years) and crocodiles (70+ years).<br />
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But for a bird, Wisdom is off the charts. In 1986, according to <a href="http://www.stanford.edu/group/stanfordbirds/text/essays/How_Long.html">Dr. M. Kathleen Klimkiewicz</a> of the Bird Banding Laboratory (USFWS), the longest lived bird was another albatross that clocked in at 37 years and 5 months. And even THAT was an old-timer for a bird. Most avian species live between 3 to 20 years.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=1554074150&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Because most of us are far more familiar with dogs than albatrosses, I will leave you with one final frame of reference. The American Kennel Club will not register pups from females breeding past the age of 12 years. Wisdom has our dogs beat almost six times over!Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-61950402420862284992011-03-07T14:27:00.000-08:002011-03-07T14:28:20.512-08:00The Sperm Queen passes away: RIP JoGayle Howard<div class="separator" style="clear: both; text-align: center;"><a href="http://nationalzoo.si.edu/AboutUs/Staff/BiosAndProfiles/images/HowardJoGayle.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="http://nationalzoo.si.edu/AboutUs/Staff/BiosAndProfiles/images/HowardJoGayle.jpg" width="221" /></a></div><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0823963179&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe> Photo Credit: <a href="http://nationalzoo.si.edu/AboutUs/Staff/BiosAndProfiles/HowardJoGayle.cfm">Smithsonian National Zoological Park</a><br />
<br />
<b><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=B000N0C7D0&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Dr. JoGayle Howard</b>, well-known for her ability to help even the most not-in-the-mood endangered species breed in captivity, passed away Saturday at the age of 59. She is perhaps best known for her role in the birth of giant panda cub Tai Shan at the National Zoo in 2005. She also played a critical role in captive breeding of the highly endangered clouded leopard and black-footed ferret.<br />
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<br />
As a <span class="PTitle">theriogenologist (drop that one in conversation to impress your friends), Dr. Howard pioneered techniques in </span>sperm cryopreservation, sperm processing and laparoscopic artificial insemination.<br />
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From <a href="http://smithsonian.com/">Smithsonian.com</a>:<br />
<br />
<blockquote>"Howard, the subject of the upcoming Smithsonian Channel program <i><a href="http://www.smithsonianchannel.com/site/sn/show.do?show=137812">Nature’s Matchmaker</a></i>, pioneered new techniques in animal reproduction. She achieved “countless breakthroughs, trained hundreds of students and foreign colleagues and played an instrumental role in saving species,” reports the National Zoo, where Howard worked for three decades. Howard’s reputation as an animal matchmaker and reproductive sleuth, solving the difficult issues of breeding endangered species, garnered her the sobriquet, “Sperm Queen,” a nickname she relished."</blockquote><br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0743299884&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Sperm Queen? Perhaps she will become the patron saint of <i>The Birds and the Bees</i>.<br />
<br />
I can think of nobody more fitting.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-20107276640204331712011-03-04T17:04:00.000-08:002011-03-04T17:12:31.431-08:00Earwig genitals: Size really does matter!<div style="text-align: center;"><a href="http://www.pdclipart.org/albums/Animals_Bugs_Insects/Earwig.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://www.pdclipart.org/albums/Animals_Bugs_Insects/Earwig.png" /> </a></div><br />
People spend a lot of time talking about the size of male genitals. One has only to type "jokes about penis size" in Google to discover that there are no fewer than 387,000 pages about the topic!<br />
<br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0142002593&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe> "So this sailor walks into a bar with an earwig perched on his shoulder..."<br />
<br />
Wait a minute. This blog is about <i>animal</i> behavior. Let me focus on the earwig!<br />
<br />
Copulation presents any number of challenges for earwig males. They need to copulate often enough - and long enough - to ensure that sperm are transferred successfully. If a female has previously mated, it may take even more (or lengthier) copulation to remove or overwhelm sperm left by the previous suitor.<br />
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As I have argued in <a href="http://bird-n-bee.blogspot.com/2011/02/why-do-females-sleep-around-geometry-of.html">previous</a> <a href="http://bird-n-bee.blogspot.com/2011/03/sexual-conflict-and-infanticide-when.html">posts</a>, extra sex may not be in the best interests of a female. She may only need to mate once to have all of her eggs fertilized. This sets the stage for behavioral and evolutionary antagonism between the sexes: what is good for the goose is not good for the gander and <i>vice versa</i>. That is a <a href="http://bird-n-bee.blogspot.com/2011/02/why-do-they-do-that.html">common theme</a> in this blog!<br />
<br />
Enter male genitals. In some animals, males have evolved penis shapes that make it difficult for females to disengage. For example, male genitals may swell in size or protrude anchors while inserted, making it difficult for the female to end copulation. Longer male genitals may be more effective in removing the sperm of rivals from the female reproductive tract. Hence male genital shape evolves in response to both females and other males.<br />
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But this is not the case in earwigs. Females can end copulation any time just by walking away. <br />
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<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=117202152X&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Emile van Lieshout of the University of Melbourne <a href="http://www.springerlink.com/content/r7p8618313372481/">published a study</a> in the February issue of <i>Behavioral Ecology and Sociobiology</i> about genital size and reproductive success in the earwig <i>Euborellia brunneri</i>. Males have unusually long ejaculatory ducts (by "unusual" I mean longer than the entire body) with a structure at the tip for displacing rival sperm. Males with the longest ducts therefore have the greatest advantage in sperm competition because they can place sperm beyond the reach of less-endowed rivals.<br />
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But wait: females of the species each have an extremely long spermatheca ("sperm receptacle") that matches and complements male genitals. Females clearly have not been neutral bystanders in the evolution of genitals in this species!<br />
<br />
So who is winning the battle of the sexes? The study addressed this question by examining how often males and females copulate -- and for how long. If males are winning, they should copulate longer with females that have already mated with other males (sperm competition). If females are in control, however, copulation time should be shorter after they have already mated and obtained sperm. <br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0207137544&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Copulation diminished after mating experience in <i>both</i> sexes: virgin males and virgin females copulated more often than males and females that had already mated. However, the duration of each copulation did not differ with mating experience in <i>either</i> sex. The battle of the sexes seems to have ended in an evolutionary standoff.<br />
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But things are not always what they seem. Duration of copulation varied among males with different sized genitals! Males with lengthier genitals copulated significantly longer (but not more often) than less-endowed males.<br />
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<br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0674035402&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>There seems little doubt that in earwigs, at least, females prefer males with bigger genitals. But the female preference is "cryptic" because well-endowed males do not win more copulations than those with smaller genitals. They may, however, fertilize more eggs because they have more time (and reach) to remove the sperm of competitors and replace it with their own.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com3tag:blogger.com,1999:blog-8160549279544906425.post-31016252347813695182011-03-02T18:57:00.000-08:002011-03-03T04:04:31.626-08:00Sexual Conflict and Infanticide: When the Battle of the Sexes Gets Ugly<div class="separator" style="clear: both; text-align: center;"></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEghG3bP1Jo5RZ-zMQkEV4M1XLuF2N14tCWZ_5kr7V0Q2Km8TEHcuP_ac-V6UZHfXnLvhuVll67Ey28pjVkaVLRKCuECpiVzmDJ1cdFolu3qAymPXxs1tqEm950MY9QxMhx5sRsWya4u4A0/s1600/Macaque-monkey1454.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEghG3bP1Jo5RZ-zMQkEV4M1XLuF2N14tCWZ_5kr7V0Q2Km8TEHcuP_ac-V6UZHfXnLvhuVll67Ey28pjVkaVLRKCuECpiVzmDJ1cdFolu3qAymPXxs1tqEm950MY9QxMhx5sRsWya4u4A0/s320/Macaque-monkey1454.jpg" width="202" /></a></div><br />
Imagine you are a theoretical male mammal. You recently hit puberty and are on the prowl. By this, of course, I mean you go out looking for females to have sex with. But woe is you: all the females are either already pregnant or nursing and in not in the mood for love. You could wait around patiently for the nursing female to finish up and become receptive -- or you could do something absolutely sinister. You could bite her young in the head and kill them.<br />
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"Egad! That seems rather churlish!" you might be thinking (if you are the sort to use words like "churlish"). But for a male mammal, such a dastardly deed could have evolutionary payoffs: when a female mammal loses her offspring she quickly becomes fertile once more. Of course there is no payoff to the killer if she scampers off to have sex with somebody else. But in many species it is precisely the killer of her offspring that she mates with.<br />
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The question is: why?<br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0202362213&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>A <a href="http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WMD-5207B6J-1&_user=687439&_coverDate=04%2F07%2F2011&_rdoc=1&_fmt=high&_orig=gateway&_origin=gateway&_sort=d&_docanchor=&view=c&_searchStrId=1662507238&_rerunOrigin=scholar.google&_acct=C000038299&_version=1&_urlVersion=0&_userid=687439&md5=5131615104d4077e8e8f5810efd8c86e&searchtype=a">new study</a> in the April issue of <i>Journal of Theoretical Biology</i> attempts to answer this question, at least for primates. Because we are primates - and yes we have been known to do a little infanticide now and then - the study may be of particular relevance.<br />
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James Lyon and his colleagues at the University of South Florida developed a little game that theoretical primates could play. (biologists like to play little theoretical games: remember John Maynard Smith from my <a href="http://bird-n-bee.blogspot.com/2011/02/sex-and-red-queen.html">last post</a>) In this game there are three contestants: females with infants, potential fathers of the infants, and newcomer males. Strategies for males in the game included either attacking, defending, or remaining neutral toward offspring, whereas strategies for females were to mate either with the insider male or the newcomer male.<br />
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While the math is a bit complex, the outcome is fairly straightforward: the best strategy for females is to mate with <b>both</b> males because it reduces the likelihood of infanticide. A male, on the other hand, only won the game with infanticide if he was a new arrival (in which case he could not be the father of any offspring) or if he was a resident who had recently risen to higher rank (but only if he stands a good chance of mating with the mother of the offspring he killed).<br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0521772958&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>The model appears to be spot on: females of many group-living primates are indeed polyandrous (they have sex with multiple males - see my earlier post on the <a href="http://bird-n-bee.blogspot.com/2011/02/why-do-females-sleep-around-geometry-of.html">geometry of promiscuity</a>). And when do males commit infanticide? Rarely if there is any chance they might be the father of any offspring they kill and generally only when they are likely to be the father of future replacement offspring.<br />
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Lest you think this sort of behavior is the domain of furry brutes without the higher intellect reserved for our own brand of primate, I invite you to search Wikipedia for the word "infanticide" ...<br />
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<div style="text-align: right;">Here, let me <a href="http://en.wikipedia.org/wiki/Infanticide">do it for you</a>.<br />
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</div>Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-6117952105361386342011-02-26T21:10:00.000-08:002011-02-27T06:37:15.049-08:00Sex and the Red Queen<blockquote><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=B0013H9AB4&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe> "Well, in our country," said Alice, still panting a little, "you'd generally get to somewhere else — if you run very fast for a long time, as we've been doing."<br />
<br />
"A slow sort of country!" said the Queen. "Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!" </blockquote><div style="text-align: right;">-- Lewis Carroll, "<i>Through the Looking Glass and What Alice Found There</i>" </div><br />
Would you believe that passage inspired one of the most important theories in modern biology?<br />
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A question (some would say THE question) that continues to produce one of the most heated debates among scientists is one of the most fundamental: Why is there sex?<br />
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Can you believe that we (when I say "we" I mean all of modern science, with our hoity-toity technology and molecular genetics) have not answered this question yet?<br />
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You may be thinking: "Well duh, you need sex to reproduce!" <i>You</i> may, but not everyone does. Bacteria don't, and there are way more of them than us. Certain animals don't! Entire generations of aphids reproduce asexually. In some animals reproduction is always asexual, such as the bdelloid rotifers that have been cloning themselves for millions of generations. Among fish, reptiles and birds, some species are known to avoid sex when reproducing. Everyone lays eggs, and as such everyone is female.<br />
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If you think about it, the question shouldn't be "Why sex?" It should be: "Why males?"<br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0521288843&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0521293022&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>In the 1970s a clever biologist named John Maynard Smith asked this question by playing a little game. His game went like this: suppose there exists a population in which some individuals reproduce sexually and others reproduce <b>asexually</b>. He imagined a founding population with three individuals: a male sexual, a female sexual, and a female asexual and assumed that both females could produce two eggs each. The male and female sexuals would need to get jiggy and produce a son and a daughter from their two eggs, while the female asexual made a couple of daughters from hers.<br />
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Already the asexuals went from 1/3 of the population (sex male: sex female: asex female) to 1/2 of the population (sex son: sex daughter: asex daughter: asex daughter). Playing the game for just one more generation puts the asexuals ahead! The sexual son and daughter make a couple of offspring (a boy and a girl), but the two asexual daughters make two female offspring apiece for a total of four asex granddaughters! Hence after two rounds of mating asexuals have the numerical advantage of 2/3 of the population. And that advantage increases with each additional generation. <br />
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Sex is a losing strategy in a pure numbers game because <b>males don't make eggs</b>.<br />
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Now that fundamental question doesn't seem quite as lame, huh? So .. Why males?!?<br />
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The answer must be that the numbers game does not give asexuals an advantage in most species of plants and animals.<br />
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Cue the heated debate. The scientific literature is full of theories, many of them heavy on the math, many of them heavy on the genetics, but two of the main contenders are fairly intuitive.<br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=B00005YUPW&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>The first contending theory, credited to another clever biologist named Alexy Kondrashov, is that sex evolved because it made possible the elimination of bad mutations from sexual populations while asexual populations accumulated more and more harmful mutations. In sex we shuffle up our chromosomes and only pass on half to each offspring. Because each offspring is a random half-mix of each parent there is a good chance it might luck out and NOT inherit a particular bad mutation. Unfortunately some of its brothers or sisters probably will, but natural selection takes them -- and their bad mutations -- out of the gene pool. Asexuals, however, pass on bad mutations to ALL their offspring, some of whom will produce even more new and different bad mutations in addition. The gene pool gets more and more polluted over time and puts asexuals at a disadvantage in the game.<br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0060556579&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>The second contending theory, credited to yet another of those clever biologists named Leigh Van Valen, is all about the Red Queen. What if, in an evolutionary sense, it takes all the running you can do to stay in the same place?<br />
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In this version of the game, sexual shuffling results in all sorts of new combinations of chromosomes each generation. Let's say a particular combination fell into evolutionary disfavor in the past, but then the environment changed in a way that favors it once again. No problem! A little sex and we get that combination back! But asexuals are out of luck because their offspring still have the SAME combinations their parents had. If natural selection removes a particular asexual combination from the population it never comes back.<br />
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Suppose natural selection kept changing directions, back and forth. It would take all the running (in an evolutionary sense) that a population could do to keep in the same place -- the place of non-extinction! <br />
But does it really work that way? Why would natural selection keep changing directions?<br />
<br />
<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=1570616116&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>The work of Curtis Lively (the last clever biologist I will mention today) and his colleagues at Indiana University have put the Red Queen to the test by examining a snail that plays John Maynard Smith's game. Some populations of <i>Potamopyrgus antipodarum</i> are comprised ONLY of asexual females. In other populations, however, there are a mix of sexual males, sexual females, and asexual females.<br />
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Why don't asexuals win Maynard Smith's game in these particular populations? The answer may seem surprising: some populations get worms!<br />
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Various species of trematode parasites infect <i>Potamopyrgus antipodarum</i> and cause them to become infertile. Infertility, as far as natural selection is concerned, is the same as death. You can't pass on your genes to the next generation. <br />
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The worms are best able to infect snails with genetic combinations that are least resistant to infection. What happens to those combinations in a pond full of trematodes? They don't get passed on. The remaining snails reproduce and fill out the next generation. Common snail genotypes become rare and rare genotypes become common. Any versions of the worm that can infect the new snail population now have the advantage. The new genetic combination in the snails does not enjoy its supremacy for long. This is called frequency-dependent natural selection: the fitness of a genotype depends on its frequency: high fitness when rare, low fitness when common. <br />
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Remember the snail genotype that was eliminated by trematode infections in the first round? When the trematode population changes direction, wouldn't it be great for the snails to get that genotype back? They can -- if they can have sex! Asexuals, alas, are out of luck.<br />
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Dr. Lively and his colleagues found that trematode parasites are most common in ponds with sexual snails -- the more parasites, the more males. They also found that particular snail genotypes rose and fell in frequency over time in ponds with parasites. And that parasites in ponds were best at infecting whatever snail genotype was most common at the time.<br />
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All of these outcomes support a Red Queen hypothesis that snails are evolving quickly (in terms of genetic changes over time) but staying in the same place (disfavored genotypes later become favored and then disfavored all over again).<br />
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The Red Queen hypothesis may or may not turn out to be the ultimate explanation for sex in all species that practice it, but in <i>Potamopyrgus antipodarum</i>, at least, it can keep them one step ahead of their asexual competitors.<br />
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Time to quit writing for now -- I'm late for a very important date.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-30143148235384290202011-02-23T18:27:00.000-08:002011-02-23T18:30:51.625-08:00Monogamy Can Be Stressful!<div class="separator" style="clear: both; text-align: center;"><a href="http://upload.wikimedia.org/wikipedia/en/4/45/Wed-dress-004.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="http://upload.wikimedia.org/wikipedia/en/4/45/Wed-dress-004.jpg" width="224" /></a></div><br />
Remember your high school prom? Some of you were fortunate to secure a date right away. If so, this article is not about you. But you can eavesdrop if you like.<br />
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This article is about the rest of us. The girls who watched all the popular boys ask other girls first. And maybe even the less popular boys ask other girls first. Don't worry, it was just as bad for many boys but the rejection was more direct and unpleasant. We got to ask the popular girls first and be told no. And then we got to ask the less popular girls .. and be told no.<br />
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The good news is that most of us eventually got a date. The bad news is that many of us got a date with someone who was not our first choice. Or second choice. Or third choice.<br />
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And that is how it works in species with monogamous breeding systems. Just like prom sorts the high school population into nonrandom pairs of teenagers in formal wear, so too does monogamy sort a breeding population into pair-bonded couples.<br />
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Some of these pairs are quite happy with one another -- after all they got their first picks. Some of these pairs, however, are not so pleased with the way things turned out. They not only did not get their first or second pick, they ended up with a partner (maybe a partner for life!) that others had already rejected. <br />
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The matter might end there if such species were both sexually and socially monogamous. The females picked first may indeed be both. After all, they got the best males. But the males picked first have incentives to be socially, but not sexually, monogamous. After all, it may only cost a little sperm to dally with females paired with other males. Which places those picked-over females into the rather difficult position of deciding whether to mate only with their partner or cuckold the poor fellow. (see my earlier post about the <a href="http://bird-n-bee.blogspot.com/2011/02/why-do-females-sleep-around-geometry-of.html">geometry of promiscuity</a>)<br />
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This is why monogamy can be so stressful!<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0764138502&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Australian scientists Simon Griffith and <a href="http://sarahpryke.com/">Sarah Pryke</a> at Macquarie University and William Buttemer at Deakin University recently took an <a href="http://rspb.royalsocietypublishing.org/content/early/2011/01/25/rspb.2010.2672.abstract">experimental approach</a> to asking just how stressful monogamy can be. They compared levels of the stress hormone corticosterone in female Gouldian finches (<i>Erythrura gouldiae</i>) that were able to pair with the male of their preference versus females paired with a less preferred male. Stress hormone levels were four times higher in females paired with low-quality males! <br />
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The stakes are particularly high for female Gouldian finches because they are genetically incompatible with males of certain (non preferred) color morphs and suffer elevated mortality rates among the offspring of such pairings. It is not entirely surprising that stressed females with less-than-ideal mates are the most likely to cheat.<br />
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Therein lies the difference between social and sexual monogamy. I'm getting stressed out just thinking about it!<br />
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<span style="color: #0b5394;">Hey readers: leave a comment! What do you think of The Birds and the Bees?</span>Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-80337132945875768522011-02-22T19:36:00.000-08:002011-02-23T04:02:52.965-08:00VermilionToday.com - Whooping Cranes return to White Lake<a href="http://www.abbevillenow.com/view/full_story/11549027/article-Whooping-Cranes-return-to-White-Lake?instance=home_news_lead&sms_ss=blogger&at_xt=4d64802a2d8086e5%2C0">VermilionToday.com - Whooping Cranes return to White Lake</a><br />
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<div class="separator" style="clear: both; text-align: center;"><a href="http://www.fws.gov/northflorida/WhoopingCrane/Crane-Images/flying-wc.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="235" src="http://www.fws.gov/northflorida/WhoopingCrane/Crane-Images/flying-wc.jpg" width="320" /></a></div><div class="separator" style="clear: both; text-align: center;"></div><div style="text-align: center;"> Image courtesy of <a href="http://www.bringbackthecranes.org/">Whooping Crane Eastern Partnership</a><a href="http://www.photos8.com/"></a></div><br />
In a week in which the animal news was all about some jerk(s) <a href="http://www.aolnews.com/2011/02/20/endangered-whooping-cranes-found-shot-to-death/">shooting endangered Whooping Cranes</a> in Alabama, Georgia and Indiana, it is great to hear about their reintroduction in Louisiana.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0803234961&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>The species went through a genetic bottleneck of decidedly non-biblical proportions in 1938, when only 14 adults were alive on the planet. Travis Glenn, Wolfgang Stephan and Michael Braunt of the University of Maryland and the Smithsonian Institution demonstrated in a <a href="http://www.uga.edu/srel/Reprint/2394.htm">1999 study</a> that only one-third of the species' genetic variation remains in the approximately 150 birds living today.<br />
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To get your mind around that, imagine that all of the nearly seven billion humans on the planet - except for 14 random individuals - suddenly died. What would the survivors look like? Who knows - they were just lucky enough to be in the right place at the right time. Do you think those 14 humans would contain amongst them all the genetic variation of our species?<br />
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Not even close. We have two sets of 23 chromosomes, which means that an absolute maximum of 46 different versions of every gene could be conserved. And that is only in the extremely unlikely event that every single one of the 14 survivors was carrying two different and unique versions of every gene in the genome. <br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=155407343X&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>The bad news for Whooping Cranes is that even when boneheaded people aren't shooting them they have a hard time staying one step ahead of extinction. They have small populations (see above problems with small populations and genetic diversity), they produce small broods of two eggs and <a href="http://www.jstor.org/pss/4160389">rarely raise more than one of them</a> (a curious habit I will be writing about in the future), and do not even start mating until several years after reaching sexual maturity.<br />
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So good luck to the Whooping Cranes re-introduced to Louisiana this month after sixty years. I am quite afraid you are going to need it.<br />
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And to the people of Louisiana: For Pete's sakes, don't shoot them!<br />
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<div style="color: #660000;"> (A note to my readers: Please leave a comment on this or any other post on The Birds and the Bees! I would love to hear what you think about idiots who shoot endangered species, whether or not the government should be spending so much money trying to save them (the cranes, not the idiots), or just what you think about idiots who write blogs about spider sex and related topics...)</div>Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-76422674261162554342011-02-20T18:15:00.001-08:002011-02-20T19:23:49.088-08:00What would Moses have thought of Brown Marmorated Stink Bugs?<div class="separator" style="clear: both; text-align: center;"><a href="http://njaes.rutgers.edu/images/photos/stinkbug/adult-female-full.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="213" src="http://njaes.rutgers.edu/images/photos/stinkbug/adult-female-full.jpg" width="320" /></a></div><div style="text-align: center;">The Brown Marmorated Stink Bug (<i>Halyomorpha halys</i>)</div><br />
A couple of years ago, I had never heard of this little stinkmeister. I am the person in the Biology department the community outreach people contact when someone needs a bug identified. I remember clearly the first time one of these critters arrived in the mail from a concerned citizen, all nasty and decomposing in a Ziploc baggie (the bug, not the citizen). I had never seen the species before and had to do a little research to figure out that it was a recently introduced invasive species.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=1155378741&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Two years later, I suspect that most of my US readers have heard of <i>Halyomorpha halys</i> (a shield-bug in the family Pentatomidae). I plucked one off the bedroom ceiling just last week (Brown Marmies have evolved the ability to drive teenage girls screaming from a room). Even I would shriek if I lived in Doug Inkley's house: <br />
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Did that, or did that not, give you the heebie-jeebies?<br />
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There are lots of unpleasant creepie-crawlies in the world and most of them do not bother me in the least. The thing that worries me about Brown Marmorated Stink Bugs is <b>Google</b>.<br />
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My blog is about animal behavior and as a human animal I do what most Americans do when I want to investigate my environment. I don't tap my antennae around as the woodlouse does nor do I sniff around the grass like the Jack Russell Terrier. I go to Google.<br />
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To my knowledge we are the only species to evolve Googling, but I believe the dolphins are close on our tail.<br />
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Do you know what happens when you type the words "<u>marmorated</u>" and "<u>biblical</u>" into the search field of Google (at least on late Sunday evening, February 20 of the year 2011)? You find out - in 0.38 seconds - that 15,500 different web pages contain those two words. 15,500!<br />
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That is a LOT of people connecting <i>Halyomorpha halys</i> with Old Testament smiting. <br />
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Contrary to what some Televangelists and conservative radio personalities might have us think, I do not believe the Old Testament God is presently looking to smite North America. So why are these bugs expected to reach plague-level population sizes in the very near future?<br />
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Population biologists watch two general things: births and deaths. Lack of natural predators and lots of crop plants are certainly parts of the equation that lower the death rate. The other part of the equation may be that these bugs are - even for insects - especially randy.<br />
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Back in 1982, when nobody but the bug nerds had heard of <i>Halyomorpha</i> in the US, Hitoshi Kawada and Chikayoshi Kitamura at Kyoto University <a href="http://nile.tm.nagasaki-u.ac.jp/medical/PDF/AEZ-1983-18-234.pdf">published a paper</a> about the species which had been "recently noticed as a horticultural pest" in Japan.<br />
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Among their findings were that copulation time for mating was approximately 10 minutes - much shorter, the authors claimed, than other pentatomid bugs. They were also observed to copulate more than five times per day (talk about stamina!). So much sex might seem like overkill because a single copulation provides a female with fertile eggs for half of her lifespan. But Kawada and Kitamura found that more copulations extended the period over which a female produced fertile eggs.<br />
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Which turns out to be a lot: in her lifetime a female lays more than 450 fertile eggs.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0618756361&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=B0007LBM4K&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>You do the math. And maybe think about moving to the Red Sea area. Or invest in a vacuum cleaner with a really big bag.<br />
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Want to know more? Visit my <a href="http://astore.amazon.com/thebir-20">Amazon Store</a>, where I have selected a variety of books and movies related to the animal behavioral patterns I discuss in my Blog.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-40017993356346244532011-02-17T20:16:00.000-08:002011-02-20T16:46:41.518-08:00Why do females sleep around? The geometry of promiscuity.<div class="separator" style="clear: both; text-align: center;"><a href="http://blackathlete.net/artman2/uploads/2/pot_and_kettle.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="283" src="http://blackathlete.net/artman2/uploads/2/pot_and_kettle.jpg" width="320" /></a></div><br />
In the United States, we are all familiar with the human sexual double standard from our developmental years in High School. Girls who "sleep around" are sluts but guys who "hook up" with lots of girls are studs. Sexist? Sure. Unfair? You bet. Biologically meaningful? Maybe just maybe.<br />
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The very first thing I wrote about in this blog was the <a href="http://bird-n-bee.blogspot.com/2011/02/why-do-they-do-that.html">fundamental asymmetry of sexual reproduction</a>. One of the two sexes works really hard to acquire the resources to make and/or care for offspring and the other sex works really hard to mate with as many of the opposite sex as possible. Or at the very least tries to prevent other members of the same sex from joining in the fun.<br />
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Typically (but not in every species) females are the sex investing most heavily in the production of offspring because they bear the burden of making eggs. Think of eggs as a lunchbox the mother packs for the developing embryo to build its body from. Males can potentially sire large numbers of offspring by mating with multiple females (that double standard studliness). Females on the other hand, receive more than enough sperm by mating with one male. Why would they need to mate with two males? To do so would seem rather .. well, slutty.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0060556579&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>If you think about it, the double standard in humans mostly benefits men because it minimizes the chance males will be "cuckolded" (a charming word that derives from cuckoo birds known to sneak their eggs into the nests of unsuspecting neighbors). Does the double standard benefit women? Perhaps, if through sexual fidelity a female gains higher reproductive success than if she does some cuckolding. <br />
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How interesting, then, that females of many animal species mate with multiple males during a single fertile period. I will leave stories about human postmen ringing twice and turn instead to Masked Julies.<br />
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<div class="separator" style="clear: both; text-align: center;"><a href="http://www.aquariumlife.net/profile-images/masked-julie.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://www.aquariumlife.net/profile-images/masked-julie.jpg" /></a></div><div style="text-align: center;"><i>Julidochromis transcriptus</i>, the Masked Julie</div><br />
Female Masked Julies (<i>Julidochromis transcriptus</i>, a cichlid fish found in Lake Tanganyika in eastern Africa) routinely mate with multiple males. But I would hardly call them sluts. I would call them <i>shrewd</i>.<br />
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Female and male Julies cooperate in providing parental care to eggs. In theory the eggs are more likely to hatch with two parents caring for them. Many female Julies do indeed form an exclusive pair with a single male. But wouldn't the eggs do even better if three parents looked after them? Probably so, but the problem is that male Julies are not so different from male humans: they chase off other suitors.<br />
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But females have found a very clever way around this problem.<br />
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Masanori Kohda and colleagues at <a href="http://www.osaka-cu.ac.jp/english/">Osaka City University</a> in Japan recently found that female Masked Julies prefer to deposit their eggs in wedge-shaped crevices. Big males can enter the crevice, but cannot squeeze their large bodies all the way into the narrow end of the wedge.<br />
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Which is precisely where the females lay some of their eggs.<br />
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Now cue the little guy. The 98 ounce weakling who would normally be chased away by the big male. The small male finds safe haven (and unfertilized eggs!) in the narrow end of the crevice. He fertilizes and cares for those eggs, the big male cares for eggs in the wide end of the wedge, and the female gets two babysitters for the price of one. What a bargain!<br />
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If anybody ever tells you girls are no good at math, remind them that female <i>Julidochromis transcriptus</i> won the battle of the sexes with geometry.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0738205281&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=B003ONR2WE&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=B003ONR38C&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Kohda et al. (2011) recently published their study in the <a href="http://rspb.royalsocietypublishing.org/content/276/1676/4207">Proceedings of the Royal Academy B</a>.<br />
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Want to know more? Visit my <a href="http://astore.amazon.com/thebir-20">Amazon Store</a>, where I have selected a variety of books and movies related to the animal behavioral patterns I discuss in my Blog.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-64900462786147825702011-02-16T21:13:00.000-08:002011-02-20T16:47:04.605-08:00Practice Makes Perfect: Spiders Rehearse Sex<div class="separator" style="clear: both; text-align: center;"><a href="https://1368176870788812915-a-1802744773732722657-s-sites.googlegroups.com/site/agelenopsis/executive-docs/Spider%20Group.jpg?attachauth=ANoY7cpTmOKvn2K12-vbr3i3NhcybqAEF6CQcQa55nlNex0V4-SYsa2ozb-GcHgJ7KUiGsQiuo-ZD7eQ_hCJk7hrNzMs6Zj4qamZhsPZAtiI7t6d5-s4DXBt47M95mUzAFC-EfRgDQKVxzTz6ZAliWVCAmMhvR4LtwBK-ZozVPNtVirvajI2Vp59bfq9fGWqnX38OtOSu13c8IDe36uJq97zTccvJFM1IzdKb7GqxlhaFQZFwgzG9LA%3D&attredirects=0" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://1368176870788812915-a-1802744773732722657-s-sites.googlegroups.com/site/agelenopsis/executive-docs/Spider%20Group.jpg?attachauth=ANoY7cpTmOKvn2K12-vbr3i3NhcybqAEF6CQcQa55nlNex0V4-SYsa2ozb-GcHgJ7KUiGsQiuo-ZD7eQ_hCJk7hrNzMs6Zj4qamZhsPZAtiI7t6d5-s4DXBt47M95mUzAFC-EfRgDQKVxzTz6ZAliWVCAmMhvR4LtwBK-ZozVPNtVirvajI2Vp59bfq9fGWqnX38OtOSu13c8IDe36uJq97zTccvJFM1IzdKb7GqxlhaFQZFwgzG9LA%3D&attredirects=0" width="320" /></a></div><br />
Would it surprise you to learn that some animals routinely engage in what can best be described as heavy petting? Indeed male and female spiders of the species <i>Anelosimus studiosus</i> often get to third base without scoring a proverbial home run. This is because males reach sexual maturity more quickly than females and begin the process of finding a mate before the fair sex is capable of reproduction. So like many human teenagers over the ages, they just make out instead. Or if you are a scientist: they pseudocopulate ("pseudo" means "false" and "copulate" means .. well, you know what it means).<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=1554073464&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Here is how teen angst works for spiders: sexually mature males leave the nest to find a mate, scrap it up with other suitors, and remain with the contested female if the male is tough enough to drive away the competition. The only problem is that the female is not yet old enough to mate. Rather than pass the time until she sexually matures with platonic affection, the male begins drumming on her web in a particularly seductive way and she responds by offering her body in a pose that leaves little doubt as to her intentions. The male climbs beneath her and assumes the appropriate position but doesn't put his you-know-what into her you-know-what. (It's called pseudocopulation for a reason!) The pair repeat the ritual until at last the female reaches maturity and actual reproduction ensues.<br />
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<a href="http://eeb.bio.utk.edu/pruitt.asp">Jonathan Pruitt</a> and <a href="http://eeb.bio.utk.edu/riechert.asp">Susan Riechert</a>, of the University of Tennessee, wondered what all the making out was about. After all, it seems like rather a lot of wasted energy at first glance. Pruitt and Riechert suspected that the spiders might in fact be rehearsing for copulation -- that by practicing spiders might be better at closing the deal when the time finally arrives. As the authors discuss in a forthcoming article in the journal <a href="http://dx.doi.org/10.1016/j.anbehav.2011.01.011">Animal Behaviour</a>, being good at copulation might be particularly important for a male, who needs to be quick about it before a stronger competitor comes along to drive him off. If she gets cozy with subsequent males, his sperm are more likely to do the fertilizing if he manages to inseminate her first.<br />
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There is also the rather unpleasant possibility that if he isn't quick enough the female will eat him. And you thought dating humans was tough!<br />
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Pruitt and Riechert found that "nonconceptive" sexual experience resulted in speedier mating in <iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=3642075576&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>sexually mature pairs and that spiders with multiple experiences were even quicker to mate. This would seem to confer the previously described advantages to males, but what do females get from these quickies? Females with nonconceptive sexual experiences produced heavier egg masses. Pruitt and Riechert suggest that females may invest more heavily in offspring sired by high-quality males.<br />
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How can male spiders demonstrate their quality? Possibly through the stamina it takes to copulate after so much pseudocopulatory foreplay.<br />
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Want to know more? Visit my <a href="http://astore.amazon.com/thebir-20">Amazon Store</a>, where I have selected a variety of books and movies related to the animal behavioral patterns I discuss in my Blog. Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-37723205819254159972011-02-15T20:46:00.000-08:002011-02-15T20:53:11.116-08:00Who says Natural History Museums are boring and stuffy?<div class="separator" style="clear: both; text-align: center;"><a href="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/images/orangutan.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="266" src="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/images/orangutan.jpg" width="320" /></a></div><br />
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Get your tickets while you can -- if you happen to be anywhere near London in the coming months.<br />
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The <a href="http://www.nhm.ac.uk/index.html">Natural History Museum</a> just opened a new (limited time) exhibit called: <a href="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/index.html">Sexual Nature</a>. Here is a promo from the Museum's web site (you need to imagine this with an English accent):<br />
<blockquote>"Anything goes in the animal kingdom, so leave your preconceptions at the door and undress the science of sex in this stimulating exhibition. </blockquote><blockquote>Explore sexual selection and different mating systems as you encounter fascinating Museum specimens, live creatures and witness dramatic BBC wildlife footage and other revealing films. The exhibition contains specimens and specially commissioned exhibits that have never been on public display before."</blockquote>I will admit laughed out loud when an imaginary voice in my head (that sounded rather like John Cleese) said "stimulating exhibition." But in all seriousness this sounds like an incredibly cool exhibition! Among the exhibits:<br />
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<div class="separator" style="clear: both; text-align: center;"><a href="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/ss_images/ss_image_gallery-walkway-pheasant.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="188" src="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/ss_images/ss_image_gallery-walkway-pheasant.jpg" width="320" /></a> </div><div class="separator" style="clear: both; text-align: center;"><b>It's the way that you do it</b></div><blockquote>"From buxom blossoms and flamboyant feathers to awesome antlers and barbed penises, the tools of seduction and reproduction are endless. You'll learn about many bizarre sexual techniques in the animal world."</blockquote><br />
And if you were wondering how hedgehogs manage the reproductive act (a prickly situation to be sure).....<br />
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<div class="separator" style="clear: both; text-align: center;"><a href="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/ss_images/ss_image_mating-hedgehogs.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="188" src="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/ss_images/ss_image_mating-hedgehogs.jpg" width="320" /></a> </div><div class="separator" style="clear: both; text-align: center;"><b>Bridled passion</b></div><blockquote>"Three specially-commissioned specimen displays of mating foxes, rabbits and these hedgehogs are sure to cause a stir. The male hedgehog is an example of a creature that uses a vaginal plug in sex to prevent other male conquests of his mate. His semen sets solid inside the female while the sperm swim to victory. Hedgehogs have to take special care when copulating."</blockquote><br />
For the voyeur in all of us (c'mon, be honest!)...<br />
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<div class="separator" style="clear: both; text-align: center;"><a href="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/ss_images/ss_image_deers-mating-image.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="188" src="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/ss_images/ss_image_deers-mating-image.jpg" width="320" /></a> </div><div class="separator" style="clear: both; text-align: center;"><b>Mating couples on camera</b></div><blockquote>"The exhibition gallery is adorned with sepia and black-and-white images depicting animals in sexual congress like this one. Large film screen panels project close-up footage of mating displays among birds, animals and insects. Some of these displays may raise eyebrows."</blockquote><br />
May raise eyebrows? Even mine are somewhere above my hairline and I've seen a lot of things in my day!<br />
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Remember what I was saying in my last post about females holding the keys to male reproductive success? Sometimes they get so bossy about it they grow a penis! Ok, not technically, but the museum has completely stolen my thunder in an upcoming post I had intended to write about female hyenas. Phooey.<br />
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<div class="separator" style="clear: both; text-align: center;"><a href="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/ss_images/ss_image_hyena.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="188" src="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/ss_images/ss_image_hyena.jpg" width="320" /></a> </div><div class="separator" style="clear: both; text-align: center;"><b>She’s the boss</b></div><blockquote>"Discover the species where females take the lead. Did you know female hyenas have extended genitals that have evolved to look like a penis and testicles? And the female spotted hyena actually leads the pack, rather than her smaller male counterpart."</blockquote><br />
Now I know what you are thinking: "Just hold it right there Mister!" because you are no doubt envisioning throngs of school children roaming through this tawdry exhibit on a Tuesday morning field trip. Fortunately the museum has produced a "<a href="http://www.nhm.ac.uk/visit-us/whats-on/temporary-exhibitions/sexual-nature/downloads/sexual-nature-content-guide.pdf">Sexual Nature Content Guide</a>" for parents and guardians. A good read for all concerned citizens.<br />
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In all seriousness, this is a unique and fascinating event that should appeal to anybody interested in the secret lives of animals (including the human animal!). It will run from 11 February to 02 October of this year. I may skip across the Pond myself and have a peep. Ticket prices are Adult £8, Child and concessions £4, Family £21. Free to Members, Patrons and children aged 3 and under. Although you might want to leave the latter with the sitter.<br />
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If you would like to read more about the exhibition, an <a href="http://www.dailymail.co.uk/news/article-1357405/How-hedgehogs-sex-mating-rituals-animal-kingdom.html">excellent article</a> appeared in the <a href="http://www.dailymail.co.uk/ushome/index.html">U.K. Daily Mail</a> today by zoologist Dr. George McGavin. There are also a number of great books in my <a href="http://astore.amazon.com/thebir-20">Amazon Store</a> that discuss animal reproductive behavior from a more scholarly perspective.<br />
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<iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=1555912923&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=B000FILILW&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0520240758&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe><iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=0805063323&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe>Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0tag:blogger.com,1999:blog-8160549279544906425.post-22150958226800188662011-02-13T18:09:00.000-08:002011-02-13T18:22:42.281-08:00Why do they DO that ???<div class="separator" style="clear: both; text-align: center;"><a href="http://birdquote.com/wp-content/uploads/2009/06/indigo_bunting.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="281" src="http://birdquote.com/wp-content/uploads/2009/06/indigo_bunting.jpg" width="320" /></a></div><br />
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When you were a kid, did you ever wonder why the little bird sings? Maybe you thought that was just how birds talk to each other. "Hey Bob! How are things with the wife and chicks?" Maybe you thought they do it to please the ears of the Creator that made them. The sounds are certainly pleasing enough to the ears of many humans. People even pay for CDs and MP3s of the stuff.<br />
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Wait a minute. Doesn't making all that noise attract unwanted attention? Like the attention of bigger birds that swoop in and eat little birds? Little birds that perch on the tips of branches, in the full sunlight (little COLORFUL birds), making a ruckus. A huge noisy ruckus that can be heard from far away.<br />
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Now that just doesn't seem very smart.<br />
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Fortunately for each songbird species (those birdies we humans classify in the Order Passeriformes), only half of them are bright, loud and stupid. The male half. Females, on the other hand (or wing in this case) tend to be rather quiet and retreating. And they are as a rule not very colorful at all. Check out the Indigo Buntings at the top of this entry. Which one is the female? Female songbirds are plain and quiet and dull and, well, camouflaged. <i>Well</i> camouflaged. Now THAT seems smart.<br />
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That's right. In the animal kingdom females are usually the smart ones.<br />
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Charles Darwin (you may have heard of him?) found this seemingly universal difference between male and female songbirds to be rather odd. Shouldn't there be ONE body color or means of communication that works well for both females and males? If natural selection favors quiet females that blend into their backgrounds, why doesn't it favor the same survival-promoting characteristics in males?<br />
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What struck Mr. Darwin as even more strange was that this difference between the sexes (sexual dimorphism) is not unique to songbirds. The same is true of many species of fish, amphibians, insects, and mammals (<i>Homo sapiens</i> comes to mind). It seemed that his tidy little idea of natural selection could not account for a great big chunk of all the species in the animal kingdom. Or even plants, many of which have distinctly different male and female flowers (guess which flowers are the largest and most colorful?).<br />
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Fortunately for him (and for all of us who study biology more than a hundred years after his death) Mr. Darwin was a brilliant naturalist. He might not have felt that way, but most scientists credit him with the greatest idea of all time. Wow, that's a tough act to follow!<br />
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But follow it he did. It occurred to Mr. Darwin that natural selection is not so much about survival, but rather it is all about reproduction. What good are traits that help you live a long time if you don't pass them on to anybody? And since males and females reproduce in dramatically different ways (consider the difference in size between a chicken egg and a chicken <i>sperm</i>) natural selection must operate differently on the two sexes. Female chickens need adaptations that help them make eggs - it takes a lot of extra food to make those eggs we so thoughtlessly crack on the skillet. Males don't need adaptations that help them get extra food. They need adaptations that help them get extra females!<br />
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Darwin called the process whereby males evolve characteristics that make them better at convincing females to have sex with them Sexual Selection. Let's face it. Some males are either sexier to females, strong enough to keep other males away from females, or both. <iframe align="left" frameborder="0" marginheight="0" marginwidth="0" scrolling="no" src="http://rcm.amazon.com/e/cm?t=widgetsamazon-20&o=1&p=8&l=bpl&asins=B003OIBHPM&fc1=000000&IS2=1&lt1=_blank&m=amazon&lc1=0000FF&bc1=000000&bg1=FFFFFF&f=ifr" style="height: 245px; padding-right: 10px; padding-top: 5px; width: 131px;"></iframe><br />
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So THAT'S what all that cock-a-doodle-dooing is about!<br />
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And that, on many levels, is what this Blog is about. Why do animals do the things they do? Usually because it has something to do with making babies. But what do giraffe necks have to do with that? Or lions killing cubs? Or fireflies pretending to be the wrong species? Or snails that don't even bother having two sexes?<br />
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Why do they DO that?<br />
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Stay tuned.Animal Professorhttp://www.blogger.com/profile/11971084760840395498noreply@blogger.com0