Snake sex chromosomes say less about sex and more about survival
Snake sex chromosomes say less about sex and more about survival | Whitehead Institute
The problem is that it's not as simple to find out if a snake is male or female as it is in many other animals. On the outside, male and female snakes look similar. However, with a bit of experience, there are ways to differentiate between the two. The following methods of sexing snakes should only be done by experienced caretakers or veterinary staff. If you are a beginner in snakes and want to know the sex of your snake, find an experienced reptile keeper or vet to demonstrate these methods to you.
How to Determine a Snake's Sex
Researchers studied the genes on the sex-specific chromosomes of three species of snakes, including the five-pacer viper left , the pygmy rattlesnake center and the mountain garter snake right for clues about the forces that shaped their evolution. Now, a new study from research scientist Daniel Winston Bellott in the lab of Whitehead Institute Member David Page broadens our understanding of what makes a gene able to survive on a sex-specific chromosome by looking at one especially slithery branch of the evolutionary tree: snakes. Comparing surviving genes on snake sex-specific chromosomes to those that are lost to the ravages of time can teach scientists about the evolutionary pressures that shaped sex chromosomes as we know them today. Instead, many of these genes are essential to the survival of the animal, and take part in key developmental processes.
We used to assume that male snakes were in charge and females were largely passive, but that has proved to be spectacularly wrong. The anaconda's swollen body suggested she was full of food, so Rivas waited for her to throw up: snakes often vomit after a meal if they have over-eaten or are stressed, to make themselves lighter so they can flee. But instead of a typical prey, like a capybara, a reptilian tail started emerging from her mouth. The female anaconda had eaten one of her most recent sexual partners, a phenomenon known as sexual cannibalism.