News Humans

Human embryos have extra hand muscles found in lizards but not most adults

New microscope images reveal the lost tissue

hand muscles

Muscles in the back of a 10-week-old human embryo’s hand called dorsometacarpales (the two smallest horizontal muscles highlighted at center) will be lost or fuse with other muscles during development.

Rui Diogo, Natalia Siomava and Yorick Gitton

By Tina Hesman Saey

- More than 2 years ago

Human embryos are more muscle-bound than adult humans, new microscope images cataloging early development show.