Primer: Rhynie chert ($) (Curr. Biol.)
This short Primer by Strullu-Derrien et al. introduces the amazing early vascular plant fossils from the Rhynie chert. The fossils’ high level of detail is a consequence of their being embedded in a glass-like silica matrix, possibly derived from hydrothermal springs. The fossils are approximately 407 million years old, and derive from the earliest stages of vascular development so are invaluable for our understanding of the origins of vascular tissues (although as the authors observe, water-conducting tissues are more evident than phloem). Although known for their unique plant fossils, these Rhynie chert fossils also contain cyanobacteria and green algae, giving a snapshot of a very different green world, as well as fungi, lichen, nematodes and other animals. (Summary by Mary Williams) Curr. Biol. 10.1016/j.cub.2019.10.030