Have ecological niches been conserved in evolutionary time for South
Asian River Dolphins?
Abstract
The niches of species that are geographically separated can either be
conserved or diverge. This dynamic has been studied over time through
Species Distribution Modeling and quantification of niche metrics. Here
I have conducted this study for South Asian Dolphins. The Ganges River
Dolphin and the Indus Dolphins are considered sub-species but there has
been debate on this classification. The niche overlap was found to be
very low meaning Indus Dolphin which most likely separated through the
process of drainage capture has diverged from its original niche. The
niche equivalency test also showed that there is a niche divergence is
statistically significant. These dolphins could well be two separate
species given their difference in niches but further study especially
genetic studies are needed to affirm this. But the study highlights
deviations from niche conservatism for the taxa due to significant niche
shifts.