Researchers have revealed through a study that there lived a species of otter about 6 million years ago that was much bigger than today’s otters and were as big as wolves. One peculiarity of these wolf-sized otters was they had a surprisingly powerful bite.
According to researchers involved with the study, the findings provide great insight and understanding of the ecological niche that the oversized creature may have filled in the wetlands of southwest China, where these otters are though to have lived millions of years ago. The otter named Siamogale melilutra is estimated to have weighed about 110 pounds.
Scientists concluded through computer simulations that animal had much firmer jaw bones than expected and that this particular stiffness would have given the otter a surprisingly strong bite — even for its size.
Modern otters have a varied diet, with different species dining on foods that range from plants and rodents to fish, crabs and clams. Based on the new study’s findings, S. melilutra’s jaws would have been strong enough to crush the shells of big mollusks or the bones of birds and small mammals like rodents, though what exactly it ate is unknown.
To better understand S. melilutra, Tseng and colleagues compared the prehistoric critter to its living counterparts.
The team used computed tomography (CT) scans of skulls to create 3-D, computerized models showing how the jaw bones of 10 of the 13 known living otter species bend under biting forces. The team also made a model for S. melilutra, using CT scans of fossils as a guide. The work included a painstaking, digital reconstruction of the cranium based on a crushed fossil.
A comparison of all the otter jaw simulations revealed a linear relationship between jaw stiffness and animal size: Smaller otters had sturdier jaws. But S. melilutra was an outlier: The massive mammal’s modeled jaws were six times sturdier than expected. This strength, paired with the creature’s size, would have made it a formidable hunter.
The study has been published in Scientific Reports.