. Illustration of some of the apex predators in the Paja Formation biota with a human for scale. Illustration Credit: Guillermo Torres, Hace Tiempo, Instituto von Humboldt. |
Predators at the top of a marine food chain 130 million years ago ruled with more power than any modern species, McGill research into a marine ecosystem from the Cretaceous period revealed.
The study, published in the Zoological Journal of the Linnean Society, reconstructs the ecosystem of Colombia’s Paja Formation, and finds it was teeming with marine reptiles reaching over 10 meters in length that inhabited a seventh trophic level.
Trophic levels are the layers or ranks within a food chain that describe the roles organisms play in an ecosystem based on their source of energy and nutrients. Essentially, they help define who eats whom in an ecosystem. Today’s marine trophic levels cap at six, with creatures like killer whales and great white sharks.
The discovery of giant marine reptile apex predators occupying a seventh trophic level underscores the Paja ecosystem’s unmatched diversity and complexity, offering a rare view into an evolutionary arms race among predators and prey.