Paleontologists have recovered the fossilized stays of three hyaenodont species, together with one beforehand unknown to science, from Miocene sediments in Pakistan.
Metapterodon anari. Picture credit score: Steven Jasinski / SergeyAtrox1.
“Hyaenodonts had been a few of the most necessary mammalian carnivores earlier than cats and canines and the opposite mammalian predators we all know as we speak advanced and started to take over these niches, and a few of them obtained to extremely massive sizes,” mentioned Harrisburg College of Science and Know-how’s Professor Steven Jasinski.
In a brand new examine, Professor Jasinski and his colleagues examined fossils of three completely different hyaenodonts that lived between 14 and 9.5 million years in the past.
The specimens got here from the Chinji and Nagri formations of the Decrease and Center Siwaliks in Pakistan.
One of many hyaenodonts, tentatively recognized as Megistotherium or Hyainailouros, was an extremely massive species that will have reached as much as 500 kg — in regards to the dimension of a polar bear.
The fossils had been deciduous tooth from juvenile animals that had not but developed everlasting dentition, making agency identification tough.
Different fossil tooth had been recognized as a member of the genus Hyaenodon.
Whereas this wide-ranging genus is thought from many northern continents, together with North America, Europe, and Asia, these are the primary specimens from this area.
They’re additionally the youngest identified incidence of the genus and should characterize a definite species, although extra materials is required to substantiate this.
These creatures possible weighed round 30 kg, comparable in dimension to a small grey wolf or leopard.
The paleontologists additionally recognized a tooth belonging to a genus of comparatively small hyaenodonts referred to as Metapterodon.
Beforehand identified solely from African fossils, the genus is now confirmed to have traveled out of Africa through the Miocene.
Named Metapterodon anari, the brand new species may additionally be one of many youngest hyaenodont fossils revealed up to now.
“Metapterodon anari is extremely necessary each for its place amongst comparable species, but in addition its placement in time,” Professor Jasinski mentioned.
“It represents one of many final hyaenodonts and provides us potential perception right into a time when there was possible competitors between these mammalian predators and carnivorans, which had been beginning to overtake them as the principle terrestrial carnivorous mammals.”
Metapterodon anari reached about 15 kg, comparable in dimension to a big purple fox or coyote.
“The importance of those fossils lies not solely of their taxonomic identifications but in addition of their geographic implications,” the researchers mentioned.
“They affirm necessary connections between Africa and Europe through the Miocene and recommend attainable migration of hyaenodonts from neighboring areas reminiscent of China.”
“The Miocene Pakistan hyaenodonts are notably fascinating as a result of they lived alongside carnivorans, offering information on how the 2 teams competed.”
“All present options of hypercarnivores, with meat dominating their diets: a specialization that will in the end have left them weak to aggressive exclusion by carnivorans.”
The fossils additionally assist scientists higher perceive South Asia through the Miocene, a time of cooling world temperatures and shifting animal communities that helped lay the inspiration for the ecosystems we see within the area as we speak.
“Fossils should not simply an fascinating anecdote about previous animals and vegetation; they assist us perceive what adjustments have occurred and the way dwelling issues handled these adjustments,” Professor Jasinski mentioned.
“Learning them additionally may help give us clues for what adjustments might happen in our future, and concepts as to methods to cope with these adjustments.”
The workforce’s results seem within the journal PalZ.
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Ok. Mahmood et al. Hyaenodonta from the Center to Late Miocene deposits of the Siwaliks of Pakistan with a quick account of Indian subcontinent hyaenodonts. PalZ, revealed on-line April 16, 2026; doi: 10.1007/s12542-025-00766-5
