Wednesday, 21 September 2011

A New And Ancient Species Of Caniform

The fossils of Lycophocyon hutchinsoni
Caniform is the name given to a group of carnivorous mammals. Today they are a diverse group, but their ancestral forms are represented by a series of mysterious, dog-like mammals. It is thought that a creature called Miacis is the oldest caniform on Earth and indeed the ancestor of all carnivorous mammals. However a recent fossil discovery from the Santiago Formation in San Diego, California, could challenge this long standing and popular theory.

Lycophocyon hutchinsoni was discovered by Susumo Tomiya in 2011. Its name translates as twilight dog and honours the American palaeontologist J.Howard.Hutchinson. The creature is known from a collection of cranial and dentiary remains alongside a few fragments of its body and limbs. The creature evolved around 43 million years ago and died out just 3 million years later. All the fossils date from within this late Eocene time period. This creature is an important discovery. Apart from being a completely new species of caniform, it sheds light on the early evolution of carnivorous mammals.

Its teeth reveal some surprising facts about its place in evolution. While Miacis is often described as the oldest caniform, it is mysterious and its true place within the tree of life is unclear. If this creature is not the ancestor of all carnivorous mammals, then Lycophocyon fills the evolutionary gap perfectly. The carnivorous mammals, known as the Carnivorans, are divided into two groups, the Caniforms and the Feliforms. Lycophocyon potentially represents the common ancestor to both groups.