American lion wasn't a lion

Panthera atrox is known as the American lion, a fearsome Ice Age predator even larger and scarier than the modern African lion. It could weigh 350kg. (I saw the fossils once in a California museum, and just say I don't want one for a pet.) The affinity between the two felines has always been considered so close that some specialists call the extinct type Panthera leo atrox. A new study has overturned this classification. It turns out the ancient "lion" comes from a line distinct from all the modern big cats. The animal is closest to the jaguar Panthera onca. Being a giant jaguar, though, isn't any less impressive.