Large, dangerous crocodiles suffered during the Holocene, persecuted and hunted by man. Few larger Crocodylians survived into the Neocene. Smaller types fared better, the African Dwarf Crocodile and Johnston's Freshwater crocodile prospered because of their less intimidating nature. In South America, smaller Caimans of the genus Paleosuchus evolved into new forms. As the South American continent moved southwards, parts of caiman habitat became dryer and more open. Paleosuchus already had some predisposition towards land, excavating burrows, travelling over land on occasion, and being able to lift its head and neck above its body, unlike its cousins. Neosuchus became more terrestrial in the Neocene, becoming the Land Caiman (Ziphocaiman terrestris). This caiman shows clear adaptations to a terrestrial lifestyle. Its snout is deeper and less flat, slightly resembling the face of a dog or theropod dinosaur, its head is held high. Its legs are longer and more muscular, and hold the animal in a more erect gait; its feet are more compact and less splayed, ending in conical claws for traction. It is able to move quickly by a gallop and fast walk. The middle rows of dorsal armor are very prominent and well developed, attaching very tightly to the back muscles. Its tail is less paddle-shaped, and more rounded in cross-section, like that of a large lizard, and it is held higher. Its teeth are serrated and curved like a theropod dinosaur, being Ziphodont. The animal is colored a light caramel brown with darker banding, along the side the banding becomes mottled spots, and the belly is a beige-cream color. Its osteoderms lack the serrated crest seen in its ancestors. The Land Caiman measures 3-3.5 meters long and weighs up to 80 kilograms. It preys predominately on small to medium sized animals such as large rodents, ground birds, lizards and snakes, Deermara and young of the Giant Paca are taken. It is like all crocodiles, an opportunist, scavenging and plundering eggs and nestlings. Each Land Caiman excavates at least one burrow, which is several meters long, it is most active in the afternoon, morning, and twilight, sheltering during the middle of the day. The mating season for land caimans is during the end of spring and the beginning of summer. Usually they are aggressive at close quarters, being able to avoid each other actively by sight on the plains. In the breeding season, males will choose a patch of ground fairly close to their burrow, and will call in the afternoon with loud bellows. The male will mate with any females that arrive, and will repel any interloping males with biting and shoving. The female will bury the 15-20 eggs in a nest of rotting vegetation, which she usually places inside her burrow, blocking access to it by sitting at the entrance, actively defending against intruders. The young will remain with her mother around her burrow for up to a fortnight, after which they disperse into nearby undergrowth. Lifespan of the Land Caiman can be from 60-70 years, older males usually accumulate scars and scrapes across their armor. In the Subtropical Pampas to the south occurs a smaller relative, the Grass Caiman (Ziphocaiman varanoides). This Caiman reaches between 1.5 and 2 meters and weighs up to 35 kilograms, and is lighter in coloration than its relative. It feeds mostly on small animals, particularly invertebrates, lizards, young birds and small rodents. The mating season is in late summer, and the female lays up to 20 eggs. Lifespan of this animal is between 40-55 years.