This is Mazon Monday post #159. What's your favorite Mazon Creek fossil? Tell us at email:[email protected].
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An artist’s rendering of Melanedaphodon hovaneci, a reptile-like mammal ancestor that lived in what is now Ohio more than 300 million years ago. Henry Sharpe
Arjan Mann is lead author of a paper that describes a new edaphosaurid, Melanedaphodon hovaneci, from the late Pennsylvanian Period around 310 million years ago. The paper appeared in the in the journal Nature. The animal is a ancestor to mammals that provides clues to the origin of herbivory in the mammal lineage. It was described from a few specimens found at famous Diamond Coal Mine in Linton, Ohio, which was in operation from 1855 to 1921. Fossils from the site are found in cannel coal, which was used to manufacture kerosene during the 1800's.
Abstract
Herbivory evolved independently in several tetrapod lineages during the Late Carboniferous and became more widespread throughout the Permian Period, eventually leading to the basic structure of modern terrestrial ecosystems. Here we report a new taxon of edaphosaurid synapsid based on two fossils recovered from the Moscovian-age cannel coal of Linton, Ohio, which we interpret as an omnivore–low-fibre herbivore. Melanedaphodon hovaneci gen. et sp. nov. provides the earliest record of an edaphosaurid to date and is one of the oldest known synapsids. Using high-resolution X-ray micro-computed tomography, we provide a comprehensive description of the new taxon that reveals similarities between Late Carboniferous and early Permian (Cisuralian) members of Edaphosauridae. The presence of large bulbous, cusped, marginal teeth alongside a moderately-developed palatal battery, distinguishes Melanedaphodon from all other known species of Edaphosauridae and suggests adaptations for processing tough plant material already appeared among the earliest synapsids. Furthermore, we propose that durophagy may have provided an early pathway to exploit plant resources in terrestrial ecosystems.
Figure 2
CM 93779, a natural mold of partial skeleton comprising a right maxilla, a right pterygoid, a left parietal, a left frontal, a parabasisphenoid, and postcranial bones (Fig. 2). Collected by John Spina and donated by Scott McKenzie.
Smithsonian Magazine has a nice summary article.
While plants first colonized land 470 million years ago, there haven’t always been animals able to eat them. Being a herbivore requires specialized traits like durable teeth to break down tough plant material and a large gut housing microbes capable of digesting cellulose. As a result, researchers have long thought that large animals did not start chowing down on greens until the early Permian period around 300 million years ago.
But the discovery of a new fossil critter may push this dietary revolution back millions of years. In a study published today in the journal Scientific Reports, Smithsonian paleontologists Arjan Mann and Hans Sues named a new species of ancient reptile-like mammal ancestor that had chompers reminiscent of living lizards like blue-tongued skinks who devour everything from fruits and veggies to insects.
“The similar tooth morphology present in this fossil animal may indicate the earliest inklings of herbivory,” said Mann, a Peter Buck Postdoctoral Fellow at the National Museum of Natural History and the lead author of the new study. “The adaptation of herbivory is now much earlier than previously recognized.”
Museum paleontologist Arjan Mann holds the fossilized skull of a Gorgonops, another type of reptile-like mammal ancestor that lived around 260 million years ago in what is now Zambia. Arjan Mann
