PubMed · 2026-01-26
Scientists conducted the most comprehensive analysis yet of how seeds evolved over 350 million years, tracing their origins from the late Devonian period through the end-Permian extinction. The study reveals how key innovations—like pollen-capturing structures and protective seed coats—gradually shaped the seeds that now sustain nearly all plant life on Earth.
A new family tree built from 79 fossil seed species and 89 physical traits—with only 24% missing data—confirms three major ancient seed groups: lagenocarps, trigonocarps, and cardiocarps, with three genera serving as previously unknown connecting links between them.
The origin of the true seed depended on two key biological breakthroughs: complex chemical signaling to guide sperm through the seed wall, and localized cell death that carved out a specialized pollen-receiving chamber at the seed's tip.
The end-Permian mass extinction (~252 million years ago) wiped out plants bearing lagenocarps and trigonocarps, likely because features of their reproductive biology made them vulnerable to desiccation during the crisis.