wombat and snails
By: Krissy Collins
This large, pudgy mammal is a marsupial, or pouched animal, found in Australia and on scattered islands nearby. Like other marsupials, wombats give birth to tiny, undeveloped young that crawl into pouches on their mothers' bellies. A wombat baby remains in its mother's pouch for about five months before emerging. Even after it leaves the pouch, the young animal will frequently crawl back in to nurse or to escape danger. By about seven months of age, a young wombat can care for itself.
Wombats use their claws to dig burrows in open grasslands and eucalyptus forests. They live in these burrows, which can become extensive tunnel-and-chamber complexes. Common wombats are solitary and inhabit their own burrows, while other species may be more social and live together in larger burrow groups called colonies.
Wombats are nocturnal and emerge to feed at night on grasses, roots, and bark. They have rodentlike incisors that never stop growing and are gnawed down on some of their tougher vegetarian fare.
The field and pasture damage caused by wombat burrowing can be a destructive nuisance to ranchers and farmers. Wombats have been hunted for this behavior, as well as for their fur and simply for sport. Some species (the northern hairy-nosed wombats) are now critically endangered, while others (the common or coarse-haired wombat) are still hunted as vermin. Space for all wombats is at a premium as farm and ranch lands increasingly replace natural space. http://animals.nationalgeographic.com/animals/mammals/wombat/
The main habitat for the Common Wombat is the temperate forest-covered areas of southeastern Australia. The species tends to avoid rainforests and is often found in the mountainous areas. In southern Queensland and northern New South Wales it is found only in sclerophyll forest above 600 m
both wombat and snails (cartoon)
The snail can retreat into its shell when danger threatens. The spiral shell gives it protection from predators and from being damaged. Land snailsare very well adapted to changing weather conditions. Snails that live in moist areas usually have thinner shells.
Snails that respire using a lung belong to the group Pulmonata, while those with gills form a polyphyletic group; in other words, snails with gills form a number of taxonomic groups that are not necessarily more closely related to each other than they are related to some other groups. Both snails that have lungs and snails that have gills have diversified so widely over geological time that a few species with gills can be found on land and numerous species with lungs can be found in freshwater. Even a few marine species have lungs.
Snails can be found in a very wide range of environments, including ditches, deserts, and the abyssal depths of the sea. Although landsnails may be more familiar to people, marine snails constitute the majority of snail species, and have much greater diversity and a greaterbiomass. Numerous kinds of snail can also be found in fresh water.
Most snails have thousands of microscopic tooth-like structures located on a ribbon-like tongue called a radula. The radula works like a file, ripping food into small pieces. Many snails are herbivorous, eating plants or rasping algae from surfaces with their radulae, though a few land species and many marine species are omnivores or predatory carnivores.
Several species of the genus Achatina and related genera are known as giant African land snails; some grow to 15 in (38 cm) from snout to tail, and weigh 1 kg (2 lb). The largest living species of sea snail is Syrinx aruanus; its shell can measure up to 90 cm (35 in) in length, and the whole animal with the shell can weigh up to 18 kg (40 lb).