South Asian river dolphin display the variances needed to support their classification as separate species. Thus, at present, a single species with two subspecies is recognized in the genus "Platanista", "P. g. gangetica" (Ganges river dolphin) and "P. g. minor" (Indus river dolphin). An assessment of divergence rates in mitochondrial DNA of the two subspecies indicates that they diverged from a common ancestor around 550,000 years ago. This ancestor is thought to have been a marine Platanistid inhabiting the epi-continental seas in South Asia during the sea level rises in the middle Miocene. The earliest fossil identified as belonging to the species is only
Zoo Tycoon 2: Endangered Species 3D. "Endangered Species" contains 20 brand new animals from various countries and habitats. The expansion focuses on endangered and critically endangered animals like the Orangutan, Javan rhinoceros, Florida panther, and Giant sable antelope. However, other animals are included that are 'lower risk' and 'vulnerable' as well. "Zoo Tycoon 2"'s first expansion, "Endangered Species" updates most of the animal behaviors; basic herding behaviors were added (more advanced herding and pack behavior came out in "") and animals cannot breed with their siblings, parents or grandparents. Animal models and skins are also slightly more realistic than the animals from the original game.