The cat gap is a period in the fossil record of approximately 25 million to 18.5 million years ago in which there are few fossils of cats or cat-like species found in North America. The cause of the "cat gap" is disputed, but it may have been caused by changes in the climate, changes in the habitat and environmental ecosystem, the increasingly hypercarnivorous trend of the cats, volcanic activity, evolutionary changes in dental morphology of the Canidae species present in North America, or a periodicity of extinctions called van der Hammen cycles.

Pseudaelurus is a prehistoric cat that lived in Europe, Asia and North America in the Miocene between approximately twenty and eight million years ago. It is considered to be a paraphyletic grade ancestral to living felines and pantherines as well as the extinct machairodonts (saber-tooths), and is a successor to Proailurus. It originated from Eurasia and was the first cat to reach North America, when it entered the continent at about 18.5 Ma ending a 'cat-gap' of 7 million years. The slender proportions of the animal, together with its short, viverrid-like legs, suggest that it may have been an agile climber of trees.