There are two subclasses of mammals - first beasts and true beasts. The first group includes the detachment One-pass. They differ from the latter in that they lay eggs, but the young hatched from them are fed with milk. Real animals are divided into two superorders - marsupials and placental mammals.
The first differ from the second in that during pregnancy, the female does not form a placenta - a temporary organ that provides a link between the mother and daughter organism. But such animals have a bag that is designed to carry a cub that is born incapable of independent life. This superorder includes only one order - Marsupials. And all other orders belong to the placentals, such as artiodactyls, pinnipeds, carnivores, primates, bats, etc.
Classification
Marsupials occupy an ambiguous position in animal taxonomy. According to some systems, this group of organisms is a detachment, and according to others, an infraclass. Let's take a koala as an example. According to one of the options, its place inclassification looks like this:
- Domain - Eukaryotes.
- Kingdom - Animals.
- Type - Chordates.
- Subtype - Vertebrates.
- Class - Mammals.
- Squad - Marsupials.
- Family - Wombat.
According to another option - like this:
- Domain - Eukaryotes.
- Kingdom - Animals.
- Type - Chordates.
- Subtype - Vertebrates.
- Class - Mammals.
- Infraclass - Marsupials.
- Detachment - Bicameral marsupials.
- Suborder - Wombat-shaped.
- Family - Koala.
Characteristics of marsupial mammals
Most of the species of this order are endemic, that is, they live only in a particular area. Most often it is Australia. Almost all marsupial mammals of the planet live on this mainland. Most marsupials are listed in the Red Book.
Also, representatives of this group of animals inhabit New Guinea and are found in South and North America. Marsupials are divided into nine families: Possums, Marsupial anteaters, Bandicoots, Predatory marsupials, Coenolests, Possums, Kangaroos, Wombats, Marsupials. The oldest and most primitive of the families of this order are the Possums, from which all other animals of this group originated. Let's take a closer look at each family and its representatives.
Marsupials outside Australia
The most ancient family - Opossums. Animals belonging to this group- one of the few marsupials that live outside of Australia.
They are common in America. This family includes such marsupial mammals as smoky, oriental, brownie, velvet, American opossums. These are small animals, about 10 cm long, with a long tail and thick hair. They are predominantly nocturnal, feeding on insects and a variety of fruits. These animals are good at pretending to be dead in case of danger. Also outside of Australia, in South America, some species of kangaroos live, for example, wallabies.
Representatives of the order Marsupials living in Australia
These include most of the animals of this group. The most famous of them are mammals of the Kangaroo family. It includes such representatives as the large red kangaroo, bear kangaroo, long-eared kangaroo, western gray kangaroo, etc. These are large animals with a large tail, which serves as an additional support for them. These mammals have underdeveloped front legs, but strong hind legs, which allows them to move by jumping over long distances. The main diet of kangaroos consists of plants. The young of these animals are born only three centimeters in length, the gestation period of the female is only about 30 days (up to 40, depending on the species). In addition, kangaroo rats belong to this family. No less common in Australia are wombats. These are small animals, the muzzle of which is somehowresembles a bear, but their teeth are almost the same as those of rodents.
Wombats feed on the roots of various plants, all kinds of fruits and seeds. Their front paws have large claws, which allows them to dig the ground more efficiently, because wombats are one of the animals that spend most of their lives in burrows underground. Marsupial moles are characterized by similar behavior - they are small animals that eat beetle larvae and seeds. They also differ in that they do not have a constant body temperature.
Marsupials listed in the Red Book
The most famous of these are koalas. They are on the verge of extinction, since the only food they eat is eucalyptus leaves, and not all of them - out of 800 species of this plant, only 100 are eaten by koalas. The ring-tailed kangaroo, northern long-haired wombat, marsupial marten and others are also listed in the Red Book..
The largest and smallest animals of the order Marsupials
The largest mammal of this group is the large gray kangaroo, and the smallest is the honey badger possum, which feeds on plant pollen. The largest marsupial animal lives in Southern and Western Australia. His weight can reach fifty kilograms, and his height is a little more than a meter.
The smallest marsupial mammal - Acrobates pygmaeus - lives only in Australia. Its weight rarely exceeds fifteen grams. This animal has a long tongue, it is needed in order to beit is more convenient to get pollen and nectar of plants. Also, one of the smallest marsupials can be called a marsupial mouse, whose weight is also about ten grams.
