Abstract
Current global changes are driving many species towards extinction,
making the early detection of threatened species a priority for
efficient conservation actions. However, the threat status of many
species remains unknown because we lack primary data (e.g., population
trends), and using ecological indicator traits such as range size is not
always straightforward. Recently, the idea has emerged to link species’
current threat status to macroevolutionary indicators, e.g., rates of
extinction, diversification or niche evolution. However, to fully
utilise this approach, we need to understand the underlying assumptions
and when they are valid; namely, in which cases macroevolutionary
indicators can be used as proxies for extinction-promoting
characteristics, such as small range size, narrow niche breadth or low
evolutionary potential. Here, we assess current understanding of the
assumptions underlying the relationship between macroevolutionary
indices and contemporary extinction risk. We find that only past
extinction rates can be reliable predictors of current extinction risk.
Assumptions underlying relationships between current extinction risk and
diversification and niche evolution rates were only supported in
specific circumstances and should be tested on a case-by-case basis.
When intermediate assumptions are validated, macroevolutionary
indicators could be promising tools complementing trait-based approaches
in identifying vulnerable species.