The Yangtze River porpoise, which is endangered, has been shown to be a "distinct species" according to new research.
The Yangtze River porpoise is the only freshwater species of porpoise and is part of a group of species known as finless porpoises (Credit: Handout)
New research has suggested that the endangered Yangtze River porpoise is a completely indepedent species, contrary to previous theories about the origins of the animals.
As reported on Phys.Org, the Yangtze River porpoise was previously thought to be one of three sub-groups of a wider finless porpoise species. However, the paper published in the journal Nature Communications has instead suggested that the unique genetic makeup of these animals means they are a "distinct species".
The findings were based on a comparison of the genome of the animals known locally as "river pigs" with 48 other finless porpoises from different populations. The results show that the group had "not shared gene flow for thousands of years" with the findings suggesting that they split from other groups of porpoises at some point between 5,000 and 40,000 years ago.
Yangtze River porpoise numbers have shrunk to approximately 1000, with the species under particular threat from bycatch and shipstrike due to the heavy shipping traffic on the waters in which it lives. Animals are usually around 2m in length and the population is smaller than that of the panda, with the Chinese government relocating a number of individuals to protected reserves in 2015 in a bid to protect the species.