Data from: Ecological causes of decelerating diversification in carnivoran mammals

Clade diversification is a central topic in macroevolutionary studies.
Recently, it has been shown that diversification rates appear to
decelerate over time in many clades. What causes this deceleration remains
unclear, but it has been proposed that competition for limited resources
between sympatric, ecologically similar species slows diversification.
Employing carnivoran mammals as a model system, we test this hypothesis
using a comprehensive time-calibrated phylogeny. We also explore several
conceptually related explanations including limited geographic area and
limited rates of niche evolution. We find that diversification slowdowns
are strong in carnivorans. Surprisingly, these slowdowns are independent
of geographic range overlap between related species and are also decoupled
from rates of niche evolution, suggesting that slowdowns are unrelated to
competition and niche filling. When controlling for the effects of clade
diversity, diversification slowdowns appear independent of geographic
area. There is a significant effect of clade diversity on diversification
slowdowns but simulations show that this relationship may arise as a
statistical artifact (i.e., greater clade diversity increases the ability
of the gamma statistic to refute constant diversification). Overall, our
results emphasize the need to test hypotheses about the causes of
diversification slowdowns with ecological data, rather than assuming
ecological processes from phylogenies alone.