Ancient Caiman Attacked “Terror Bird”

Fossilized Bite Marks Reveal Prehistoric Apex Predator Clash

Fossilized evidence has unearthed a remarkable prehistoric encounter between two formidable predators in South America, offering rare insights into ancient food webs.

A Deadly Encounter

Between 16 and 11.6 million years ago, a young caiman likely preyed upon a “terror bird,” a formidable carnivorous avian known as a phorusrhacid. The discovery of puncture marks on a fossilized bone from the Middle Miocene Epoch suggests this was not a scavenging event, but a direct confrontation.

“Evidence of direct trophic [feeding] interactions between apex predators remains as a topic that has been historically understudied,” researchers wrote. “Prey is most often represented by herbivores and other animals that are not on the top of the trophic web.”

—Researchers, Biology Letters

This interaction between an aquatic apex predator and a terrestrial one significantly enhances our understanding of complex ancient ecosystems. Paleontologists are analyzing these bite marks, which indicate a substantial predator. For comparison, the average lifespan of a modern saltwater crocodile, a close relative of ancient caimans, can exceed 70 years (Florida Museum).

Unearthing the Truth

To investigate this ancient showdown, scientists created a digital model of the puncture marks found on the terror bird fossil. These tooth impressions were then compared to dental records of crocodyliforms from La Venta, Colombia, a rich fossil site where the specimen was discovered.

The findings suggest the perpetrator was likely a large caimanine, estimated to be between 15.1 and 17.7 feet long. The best match within the La Venta fauna for such a large crocodyliform is identified as a juvenile or subadult specimen of P. neivensis, the largest crocodyliform known from that ancient environment.

No Signs of Healing

Crucially, the absence of healing on the terror bird’s bone indicates that the bird succumbed to its injuries or was already deceased when the caiman encountered it. This finding further emphasizes the predatory nature of the interaction.

The study contributes to a deeper understanding of the ecological dynamics involving some of South America’s most iconic Miocene predators, suggesting that large phorusrhacids faced threats from unexpected quarters.