Ornimegalonyx, a class of extinct owl birds of the family Ornimegalonyx, survived in Cuba during the Late Pleistocene. Ornimegalonyx gigas, the largest species in the genus, has a shoulder height of more than 1.1 meters and a weight of 9-10 kilograms. It is the largest member of all the owls, even compared with the eagle-like tiger-head sea sculpture. Unlike modern owls, the Cuban giant owl is a highly habituated bird of prey with short wings, which may have lost flight ability or only a very weak ability to fly at short distances; by contrast, the Cuban giant owl’s legs are too long, making its appearance quite strange as an owl. Like other orioles, Cuban giant owls are ferocious predators. Their main prey should be large rodents and trench shrews in Cuba at that time. In addition, some small lazy birds may fall victim to their big claws. Many people think that these long-legged owls can hunt their prey in the open at a very fast speed, but some scholars think that Cuban giant owls should mainly hunt by ambush. They may lie in the treetops, and when mammals pass under the shade, they suddenly rush down and attack the head of the prey with their claws to solve the battle quickly.