New research examines how major shifts in Earth’s climate influenced the evolution of body forms in carnivorans, the mammal order that includes bears, wolves, seals, cats and dogs. The authors argue that all members of Carnivora evolved from ancestors that resembled modern mongooses, with long bodies and small round ears.
A team led by Chris Law measured skeletal shapes on more than 850 carnivoran specimens from 17 natural history museums. The sample covered almost 200 species in total, including 118 species that live today and 81 that are extinct. The researchers analysed the data to find patterns in body shape over time.
The analysis suggests two climate transitions had notable effects. The Eocene–Oligocene transition, about 34 million years ago, appears to have driven changes between families, while the Mid‑Miocene transition, about 15–13 million years ago, coincided with changes within families. The results give a clearer timeline for when major body-shape changes occurred, but researchers say more work is needed to connect these deep-time patterns to modern environmental change.
Difficult words
- carnivoran — a meat-eating mammal group like dogs and catscarnivorans
- evolve — to change over many generationsevolved
- skeletal — relating to the skeleton or bones of animals
- specimen — a single example of an animal or plantspecimens
- extinct — no longer living anywhere on Earth
- transition — a change from one state or periodtransitions
- coincide — to happen at the same time as somethingcoincided
- timeline — a list showing when events happened
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- How could studying ancient body shapes help scientists understand today’s environmental change?
- Do you think natural history museums are important for research like this? Why or why not?
- If the climate warms in the future, what changes in animal bodies might you expect to see?
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