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
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 >
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 >
There are many species of animals on Earth that spend the majority of their lives alone, including species of reptiles, amphibians, mammals, fish, insects and arachnids. Solitude is common in the animal world, and it may be only during the mating season that individual members of a species interact with each other.Full Answer >
Brainz reports the existence of at least 10 animals that are born without eyes, including the Kauai cave wolf spider, southern cave crayfish, Mexican tetra, blind legless lizard, Texas blind salamander, widemouth blindcat and fresh water hydra. Other animals born without eyes are the blind albino cave crab, Brazilian blind characid and the olm. Many of these animals live in environments with very little or no light.Full Answer >