A remarkable fossil find in Mallorca has unveiled what may be the world’s oldest known ancestor of mammals – a dog-sized predator with saber teeth that lived 270 million years ago. This discovery provides crucial new insights into how our earliest mammalian relatives evolved and spread across ancient Earth.
Published in Nature Communications | Estimated reading time: 7 minutes
An Unexpected Window into Deep Time
In the rugged cliffs of Spain’s Balearic Islands, scientists have unearthed fossil bones that are rewriting the story of mammalian evolution. The creature, known as a gorgonopsian, belonged to an extinct group called therapsids – the evolutionary lineage that would eventually give rise to all modern mammals.
Lead researcher Anne-Kathrin Baczko from Chalmers University discovered a remarkably complete specimen, including skull fragments, vertebrae, ribs, and a well-preserved leg. “We never thought we would find so many remains of an animal of this type in Mallorca,” notes Baczko.
A Portrait of an Ancient Predator
The creature, about the size of a modern husky, would have been a fearsome sight in its ancient habitat. While lacking fur and external ears like modern mammals, it possessed distinctive saber teeth – making it the oldest known animal with this iconic predatory feature. The fossil reveals an animal that moved with a gait intermediate between reptiles and mammals, suggesting an important transition in locomotor evolution.
Shifting the Timeline
The discovery’s age – at least 270 million years old – pushes back the timeline of therapsid evolution by several million years. During this period, Mallorca was not an island but part of the supercontinent Pangaea, located near the equator in a climate that alternated between wet and very dry seasons.
The research team, including scientists from Princeton University and the Field Museum, suggests this finding indicates that key mammalian traits may have first evolved in tropical regions before spreading to higher latitudes.
Glossary
- Therapsid: An extinct group of reptile-like animals that gave rise to mammals, combining features of both groups
- Gorgonopsian: A type of therapsid characterized by saber teeth and more upright leg posture than earlier reptiles
- Pangaea: The supercontinent that contained all of Earth’s landmasses about 270 million years ago
Test Your Knowledge
How old is the newly discovered fossil?
The fossil is at least 270 million years old, making it possibly the oldest gorgonopsian ever found.
Where was the fossil discovered?
The fossil was found in Mallorca, Spain, in the Balearic Islands.
What key anatomical features distinguish this creature from modern mammals?
The creature lacked fur and external ears, but had an intermediate leg posture between reptiles and mammals, and possessed saber teeth.
How does this discovery change our understanding of therapsid evolution?
It suggests that key mammalian traits may have first evolved in tropical regions near the equator, rather than in higher latitudes as previously thought.
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