Digest: Fossils, evolutionary models, and diatoms.

Adaptation to new environments by organisms has been and is of much interest in scientific research. Does the diatom lineage Stephanodiscus niagarae/yellowstonensis follow models compatible with adaptation to a new environment? Voje (2019) shows that in this lineage, none of the current models tested-decelerated evolution, Ornstein-Uhlenbeck, and random walk-fully explained how multiple traits-valve diameter, the number of costae, and spines per valve-evolved. More accurate models are needed to understand the evolutionary history of these diatoms.