There's strong scientific evidence to suggest an ancient asteroid impact off the coast of Mexico wiped out the dinosaurs, but new research suggests the giant lizards were already on the way out because some beautiful new species had begun to poison them, CNet reports.

A recent study published in the journal Ideas in Ecology and Evolution finds that the emergence of the first flowering plants, which included some poisonous species, occurs in the fossil record long before the fateful asteroid impact and just before the dinosaurs begin to decline.

University of Albany professor, evolutionary psychologist and co-author Gordon Gallup says dinosaurs may have been too slow to evolve a learned taste aversion that would allow them to associate the taste of certain foods with danger. Instead, they just kept chomping on the toxic plants despite gastrointestinal distress.

"Though the asteroid certainly played a factor, the psychological deficit which rendered dinosaurs incapable of learning to refrain from eating certain plants had already placed severe strain on the species," Gallup said in a statement this week.

Gallup and his former student Michael J. Frederick also studied whether birds and crocodilian species, which are both considered to be descendants of dinosaurs, could develop taste aversions. They found birds learn to avoid things that make them sick by recognizing them visually, while the crocodilians, like their larger ancestors, just kept chowing down.