Research on Gomphotherium
(PHYSorg.com Archaeology & Fossils)

For a long time, gomphotheres are considered to be the key link in proboscidean evolution. They are deemed as the ancestral stock of the true elephantids surviving now. The origins of stegodontids, rhynchotheres and cuvieroniines are believed to be more or less related to gomphotheres. However, gomphotheres are also considered as a problematic taxon or `dustbin` category in proboscideans. Historically, at least 60 species had been attributed into the genus Gomphotherium or its synonyms, and more than 10 species are widely acknowledged now. No agreement yet has been reached about whether these species have any synonyms or homonyms and about the systematic relations between species. The reason is that Gomphotherium has few autapomorphies (the only acknowledged autapomorphy is the oval or pear-shaped lower incisors), unspecialized feature of cheek teeth, and quite large intraspecific variation.