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The largest hoplophonine and a complex new hypothesis of nimravid evolution.

ABSTRACT: Nimravids were the first carnivorans to evolve saberteeth, but previously portrayed as having a narrow evolutionary trajectory of increasing degrees of sabertooth specialization. Here I present a novel hypothesis about the evolution of this group, including a description of Eusmilus adelos, the largest known hoplophonine, which forces a re-evaluation of not only their relationships, but perceived paleoecology. Using a tip-dated Bayesian analysis with sophisticated evolutionary models, nimravids can now be viewed as following two paths of evolution: one led to numerous early dirk-tooth forms, including E. adelos, while the other converged on living feline morphology, tens of millions of years before its appearance in felids.

SUBMITTER: Barrett PZ

PROVIDER: S-EPMC8548586 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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The largest hoplophonine and a complex new hypothesis of nimravid evolution.

Barrett Paul Zachary PZ

Scientific reports 20211026 1

Nimravids were the first carnivorans to evolve saberteeth, but previously portrayed as having a narrow evolutionary trajectory of increasing degrees of sabertooth specialization. Here I present a novel hypothesis about the evolution of this group, including a description of Eusmilus adelos, the largest known hoplophonine, which forces a re-evaluation of not only their relationships, but perceived paleoecology. Using a tip-dated Bayesian analysis with sophisticated evolutionary models, nimravids ...[more]

PMID: 34702935

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