A recent study of more than 2,000 fossils showed that members of the cat family (felids) were better hunters and more capable of survival than their dog (canid) counterparts. The study, published in the journal PNAS, found that cats out-fought and out-hunted dogs, making the most of the available resources. That led to a significant decline in the number of wild dog species that survived. “The arrival of cats to North America had a deadly impact on the diversity of the dog family,” the report’s lead author, Dr. Daniele Silvestro, says.