• Sebecids, large crocodile-like predators, inhabited the Caribbean islands millions of years ago, much later than previously thought.
• The discovery supports the GAARlandia hypothesis, suggesting a past connection between South America and the Caribbean via land bridges or island chains.
• These findings challenge current understanding of Caribbean ecosystems and highlight the potential for further fossil discoveries in the region.

Paleontologists have unearthed fossils of sebecids, extinct crocodile-like predators, in the Caribbean islands, revealing their presence in the region until approximately 5 million years ago. This discovery challenges previous assumptions about the region's ecosystem and supports the GAARlandia hypothesis, suggesting a land connection between South America and the Caribbean. The fossils, including teeth and vertebrae, indicate that these predators, some reaching up to 20 feet in length, thrived in the Caribbean long after their South American relatives went extinct.

• What: Discovery of sebecid fossils in the Caribbean, indicating their presence millions of years ago.
• Who: Lazaro Viñola Lopez (paleobiologist at the Florida Museum of Natural History), Jonathan Bloch (curator of vertebrate paleontology at the Florida Museum of Natural History), Elson Core (graduate student from the University of Puerto Rico).
• When: Sebecids lived in the Caribbean until about 5 million years ago, much later than their South American relatives (extinct around 11 million years ago). Fossils dated between 7.14 and 4.57 million years ago were found in the Dominican Republic in 2023. Teeth were found in Cuba (~18 million years ago) and Puerto Rico (~29 million years ago).
• Where: Caribbean islands, including the Dominican Republic, Cuba, and Puerto Rico.

The discovery of sebecid fossils in the Caribbean is significant because it challenges previous assumptions about the region's ecosystem and supports the GAARlandia hypothesis. This theory posits that land bridges or island chains once connected South America to the Caribbean, allowing terrestrial animals like sebecids to migrate. The fact that sebecids thrived in the Caribbean long after their South American relatives went extinct suggests that the islands provided a refuge from whatever threats caused their demise on the mainland. This discovery opens up new avenues for research into the paleogeography and ecology of the Caribbean region.

That emotion of finding the fossil and realizing what it is, it’s indescribable.

You wouldn’t have been able to predict this looking at the modern ecosystem.

The sebecid is only the tip of the iceberg.

The discovery of sebecid fossils in the Caribbean provides compelling evidence for the presence of these large predators in the region millions of years ago and offers support for the GAARlandia hypothesis. This finding challenges current understanding of Caribbean ecosystems and highlights the potential for further fossil discoveries. Ongoing research may reveal more about the ecological role of sebecids and the connections between South America and the Caribbean in the distant past.