Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Global taxonomic diversity of monotypic tetrapod families and ecological diversity of modes used by tetrapod families. These two measures of diversity correlate, with a Spearman's rank correlation coefficient of ρ = 0.9727, p < 0.001 and a linear regression of y = 0.2518x. Mass extinctions are 
end-Permian extinction, 
end-Triassic extinction and 
end-Cretaceous extinction (solid line, families; dashed line, modes).
