Dammit Jim!

According to Tangled Bank, a blog carnival is a weekly showcase of good weblog writing, selected by the authors themselves. This sounded like a nice way to motivate myself to actually write about biology (which is for some reason hard for me to do outside work) and see some other blogs. So although I’m not sure my stuff counts as ‘good weblog writing’, I submitted a couple links to the new Tangled Bank. The host Lab Cat, had this to say about me: …which brings us to sex. Dammit Jim seems to have an fixation on this subject…. Well can’t really argue with that although I probably should get some non-sex related biology up at some point.

I was browsing journals the other day trying to figure out where to send a paper when I came across a paper called Genital damage in the orb-web spider increases paternity success. I guess I have a weird sense of curiosity because I had to take a look and see what they were talking about.

When females of a species mate with several males, evolution can develop some pretty weird adaptations in males competing to fertilize the egg. More numerous, faster or cooperative sperm can improve the chances of their sperm reaching the egg first. Another alternative is to try to prevent other males from mating with that female.

As a way to interfere with other males, many species develop sticky semen to form copulatory plugs blocking other sperm access to the egg. I had heard of this before but what I didn’t know was that some insects have taken this method to an extreme and actually leaves pieces of their genitals behind in the female. These pieces had been shown to protect the males’ sperm against competition by blocking rivals from mating with the female. Similar genital breakage had been observed in spiders but since spider females like to eat their mates and males have two penis-like organs, called pedipalps, scientists debated whether a spider sacrificing one of his genitalia could be a sort of quick release to allow the males to live another day and mate again.

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I was browsing Science Daily today when I came across the headline “Rodent Sperm Work Together For Better Results”. I had thought that sperm were mindless little swimmers just looking for an egg so I had to take a look at the article (available online and free).

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I’ve been busy with school administrative stuff and field work in Cape Breton recently. Luckily, I did have the opportunity to go halibut longline fishing with one of the guys up here. That should really be ‘halibut’ fishing. We only saw one (undersize) the whole trip. It was quite a change from fishing on the west coast where even research boats can catch thousands of pounds of halibut a day.

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I just added a new book to the Darwin du Jour site. A Naturalist’s Voyage Round The World (also known as Voyage of the Beagle) is Darwin’s log of his travels on the H.M.S. Beagle. I just started reading it myself but it looks like a pretty interesting look at the history of the regions, the old methods of biology and, of course, how Darwin came up with the idea of natural selection. Project Gutenberg again provided the base text (html in this case) although I had to do a bit of conversion to make it look decent.

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