Solution (source code)

= Solution

\b[<Extinction selectivity> is systematic variation in the <probability> or rate of <extinction> among lineages with different traits], rather than trait-independent loss. Traits may be biological, ecological or geographical: for example, survival may differ between narrow-ranging and widespread taxa within the same <extinction> interval.

A test needs an explicit denominator of taxa at risk, a defined taxonomic level and time window, and a specified trait measurement. Regional disappearance is not automatically global <extinction>. Nor is an association necessarily a causal mechanism: traits covary with habitat, abundance and preservation, and their effects can change between background intervals and <mass extinctions>.