The technical way to explain this odd-looking fowl is that it’s “gynandromorphous.” But if you just want to call it “one seriously confused chicken,” that works, too.

For a new study in Nature, Michael Clinton and colleagues investigated a few of these half-male, half-female chickens they obtained from chicken farms. Gynandropmorphs show up now and then not just in chickens, but also in parrots, pigeons, and some other kinds of animals. But scientists weren’t sure how the mix-up happens, since the standard idea for sex differentiation is that the sex hormones released by the gonads either masculinize or feminize the embryo. Clinton’s team discovered that bird cells don’t need to be programmed by hormones. Instead they are inherently male or female, and remain so even if they end up mixed together in the same chicken [BBC News].

The researchers had first assumed that the half-and-half chickens followed the hormone pattern, and that they were females with some sort of chromosomal problem on the male side (the lighter half of the bird in the image, which also sports a large wattle, sturdy breast musculature, and a leg spur on its male side). Instead, they found the chickens to be almost perfectly split between male and female. The hen half was, for the most part, made up of normal female cells with female chromosomes, whereas the cockerel side contained mostly normal male cells with male chromosomes [Nature News].

Since both sides experienced the same hormone exposure, that couldn’t explain what was happening. In addition, once the team believed that cell identity was at work here, and not hormones, further experiments seemed to confirm this idea. When the researchers transplanted tissues from genetically female embryos into what would become the gonads of genetically male ones and vice versa, the transplanted cells didn’t start expressing opposite-sex characteristics [Science News].

Clinton’s study is buttressed by others that suggest the standard explanation for sex determination doesn’t apply as widely as previously thought, or at least needs some tweaking. Besides the other birds mentioned previously, some marsupials and invertebrates stray from the pattern. “These funky chickens, oddities of nature that they are, will provide new perspectives on questions of sexual identity long thought to have been resolved,” wrote Duke University cell biologists Lindsey Barske and Blanche Capel in a Nature commentary accompanying the findings [Wired.com].

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Image: The Roslin Institute at the University of Edinburgh

The following recent comments on the “Pharyngula” blog have been brought to my attention via multple emails from readers–some of them victims of rape and sexual abuse:

Fuck them [my co-blogger, our commenters, and I] all sideways with a rusty fucking knife.

Later:

The commenters are basically wetting themselves hoping Kirshenbaum comes down hard because people are saying she should be raped with a rusty knife, and Myers “likes it that way”.

I am a big proponent of free speech, however, this thread crosses the line by advocating sexual and physical violence. I have become accustomed to ignoring much of the ridicule I receive online, but keeping silent on this particular issue, is, in my mind, acceptance. Those who contacted me do not have a platform to publicly express their disgust, but I can. Rape is not a joke or game and the fact that these remarks were not removed perpetuates the notion that they’re okay.

Adam Bly and I shared a panel in 2008 at the AAAS Forum on Science and Technology Policy where he discussed the values of Seed Media Group. Further, as a former Seed blogger with many friends still on the network, I’m quite familiar with their stated mission:

Seed Media Group is committed to strengthening public interest in science and improving public understanding of science around the world.

I cannot see how the tone of commentary contributes to this goal. However, given the volume of emails I’ve already received, I’m certain it reflects poorly on Seed, science blogging, and science broadly.

The Cassini spacecraft recently passed very near the tiny moon Helene and returned amazing pictures of it.

Helene is a dinky iceball, only about 36×32x30 km (22×19x18 miles) in size (this picture has an incredible resolution of about 113 meters (123 yards) per pixel). It circles Saturn in the same orbit as the much larger Dione, and is in fact in the larger moon’s leading Trojan point: a peculiar artifact of gravity when an object orbits another. It’s a gravitational stable point, like a valley between two mountains.

Clearly battered, Helene has an oddly smooth appearance, which may be due to the feeble gravity of the moon collecting dust also trapped in the Trojan point. At The Planetary Society Blog, Emily has more info on Helene and speculates about its appearance. She also has a good description of how the Trojan points work.

Credit: NASA/JPL/Space Science Institute