An animal's risk of extinction is associated with species traits such as body size and geographic range — but this is not the case for plants. Jonathan Davies at McGill University in Montreal, Canada, and his colleagues report that, contrary to patterns seen in animals, threatened plants tend to be young species in rapidly evolving lineages.

The team studied the evolutionary history of threatened plant species on the Cape of South Africa — a plant biodiversity hot spot. Anthropogenic drivers, such as habitat loss, do not seem to endanger plants as they do animals. The authors suggest that conservation strategies for animals and plants should use different assessment criteria.

PloS Biol. 9, e1000620 (2011)