As cricket blastoderms form, cell nuclei are pulled into an egg’s remaining empty space to form the new cell layers that will shape the developing animal.
The primitive streak, a structure that emerges during mammalian and avian gastrulation, might be a byproduct rather than a landmark of the embryonic development process.
Across the tree of life, animals use sound and other vibrations to glean valuable sensory information about their environments even before they are born.
A combination of approaches, including uterus transplantation and the joining of two animals’ circulatory systems, allowed males to bear pups, according to a preprint. But some experts say the experiments were not justified.
Wolpert, who conducted research at University College London, was known for his work on morphogenesis and pattern development in embryos and for his multiple books and broadcast appearances.
Extended pluripotent stem cells from mice can self-organize to form blastocyst-like structures called blastoids that enable a closer look at early mammalian development.
In a species of freshwater turtle, embryos can move toward warmer or cooler environments within the egg and thus help choose their sexual destiny, but not all experts are convinced.