Are snakes right or left handed?

An embryo of Cape house snake (Boaedon capensis) stained to show developing muscle blocks in the trunk. The embryo shows right-handed coiling. Credit: Raul Diaz, California State University Los Angeles.

That was the question that led scientists to a study during COVID lockdown after seeing many photo of snake embyos all coiled to the right. What makes them coil to the right? Do they stay that way? Is there a right or left dominance like with us? These and many more thoughts popped to mind for evolutionary biologist Tetsuto Miyashita of the Canadian Museum of Nature when he needed a project that was socially distanced. 

“There is a touch of mystery to spirals and we are only beginning to understand how these shapes are produced in animals, such as our looping intestine, snail shells, and now these beautifully coiled snake embryos,” says lead author Alexandra Weber, now a graduate student in zoology at the University of British Columbia.

They did find out why the embryos coil to the right. It is the position of the yolk, but the how they got their is pretty cool and I suggest you pop over and read all about it here.