Fossil Find in California Shakes Up the Natural History of Cycad Plants
Published:25 Jun.2023 Source:University of Kansas
The findings are detailed in a paper by two University of Kansas paleobotanists. “The fossil record of cycads is poorly understood, and many things that have been called cycads have turned out not to be cycads at all. Here, we have a three-dimensionally preserved cone clearly assignable to cycads because it has internal anatomy and pollen grains typical of this group. However, the external morphology of this pollen cone is different from living cycads today. This finding suggests cycads aren’t really ‘living fossils’ and they probably have a more dynamic evolutionary history than previously thought.”
According to the KU researchers, their analysis of an 80-million-year-old permineralized pollen cone found in the Campanian Holz Shale formation located in Silverado Canyon, California, tells a more accurate cycad natural history -- one where the plants diversified during the Cretaceous.
“With this type of discovery, we realize during this time there were cycads that were really different than the ones today in their size, in their number of pollen sacs, in a lot of things,” Elgorriaga said. “Maybe we haven’t found that many cycad fossils as well -- or maybe we’re finding them but we’re just not recognizing them because they were so different from how they are today. They aren’t ‘living fossils’. They were different in the past.”