Many state legislatures are seriously considering human embryos at the earliest stages of development for legal personhood. Total abortion bans that consider humans to have full rights from the moment ...

The majority of fertilized eggs die and are resorbed into the body. ZEISS Microscopy/Flickr, CC BY-SA As an evolutionary biologist whose career has focused on how embryos develop in a wide variety of ...

Kathryn Kavanagh does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...