Most terrestrial animals crawl. Crawling is the characteristic mode of locomotion for most reptiles, amphibians and mammals. Insects generally crawl when they aren't flying, and terrestrial molluscs, such as snails and slugs, crawl on a single, specialized foot.Know More
Newts and salamanders crawl, as do frogs and toads when they aren't hopping. Lizards crawl with a characteristic side-to-side motion that is replicated by their close relatives the snakes. Birds generally do not crawl, though some penguins slide on their bellies for high-speed and long-distance travel. Most terrestrial invertebrates crawl, and even flying species, such as flies, moths and bees, usually revert to a stepwise, six-legged locomotion to move efficiently across surfaces.
Some animals crawl at various stages of life, but not at others. Humans, for example, typically crawl in infancy and can revert to all fours when the situation calls for it, but this is slow and inefficient relative to the adults' normal upright posture.
Many terrestrial animals have ways of moving apart from crawling, such as the horse's gallop or trot and the adult human's bipedal walk, but crawling on four, six or eight legs is common. Some animals can also form a ball and roll, such as the pangolin.Learn more about Zoology
Animals are an integral part of the Earth's ecosystem. Each organism in the ecosystem plays a role in supporting the ecological community, which means that animals play a vital role as well. Each organism in the ecosystem depends on the other organisms in the system to play its role. Without animals, there would be dysfunction within the system and human life would be disrupted.Full Answer >
Aside from the fact that an array of animal species makes life on earth more interesting, protecting endangered species has important health benefits to humans. In particular, animals fit into the well-established ecological food chain, and extinction causes a disruption to natural order, according to the National Wildlife Federation.Full Answer >
Zoos may be good or bad for animals, depending on the cleanliness of the facility, quality of the establishment, knowledge of zoo staff and other factors. Arguments supporting keeping animals in zoos argue zoos save animals from high risks of extinction. Arguments opposing housing animals in zoos cite the lack of replicating true environmental conditions, which jeopardizes the health and happiness of resident animals.Full Answer >
The top 10 endangered animals in the world, as of December 2014, are the ivory-billed woodpecker, Amur leopard, Javan rhino, numbat, northern sportive lemur, western lowland gorilla, saola, leatherback sea turtle, tiger and the Chinese giant salamander. Other critically endangered species include the mountain gorilla, northern right whale and the kakapo parrot.Full Answer >