CANBERRA, Feb. 27 (Xinhua) -- An international research involving Australians has confirmed there are three elephant species rather than two.
The team of researchers on Tuesday published the first map of the elephant family's genomic history, confirming a genomic difference between African savannah elephants, African forest elephants and Asian elephants.
David Adelson, director of Bioinformatics at the University of Adelaide, said that in order to map the genomes, researchers had to study extinct members of the elephant family such as mammoths and mastodons.
"The process required sequencing a total of 21 genomes; 10 from of the three living elephant species and from 11 ancient (extinct) elephantids from different species," Adelson told Xinhua News on Tuesday.
The University of Adelaide developed a new method for resolving the differences between species which led to the African elephants being confirmed as different from one another.
"Our new method involves using mobile genetic elements that are capable of copying and pasting themselves throughout the genome," Adelson said.
"By comparing where in the genome the elements lie in the different species, we can use the presence or absence of elements in particular locations to determine how similar the genomes of those individuals are.
"This is a completely different type of marker/method compared to the standard method of using single base changes in DNA sequences as markers for studies of genetic similarity."
The two species of African elephants had similar genetic sequencing despite the two remaining separate from one another.
"The savanna and forest elephants have been reproductively isolated for the last 500,000 years, resulting in different species," Adelson said.
"While they have largely similar genomes (for example like us and Neanderthals or horses and donkeys) they are different species."
"This is an important project as it firmly supports the existence of three distinct elephant species and in particular demonstrates that forest elephants (critically endangered) and savanna elephants, while related species, have been isolated for the last 500,000 years.
"Hopefully the major impact of this work will be to assist in conservation efforts for critically endangered forest elephants that are now poached for ivory and traditional medicines."