In detail


What are mammals? Definition:

The class of mammals covers about 5,500 species worldwide. The name derives from the fact that the offspring is suckled by the mother with milk from the mammary glands. Therefore in mammal science the mammal class is also called mammalia (lat. Mamma = breast).
By far the most common habitat of mammals is the land. More than 99% of the species are found here. Some mammals, on the other hand, are adapted to life in the water, including e.g. Whale, dolphin, seal or otter. In this context, we often talk about marine mammals. Finally, with the order of the bats, there is only one group capable of flying.
About 125 million years ago, the first mammals appeared in the Cretaceous. However, the 'triumph' of mammals only began with the decline of the dinosaurs. The comet impact on the Yucatan Peninsula led to the extinction of many species. As a result, ecological niches were freed, which could be occupied over time by more and more mammal species. At that time, there was not nearly the diversity of mammals we know today. Most mammals were small, mouse-like animals. Their small size spared them from the mass extinction, because in contrast to the tons of dinosaurs, the mammals could seek shelter under the earth's surface. In addition, the reduced supply of food, in the post-comet impact, did not present the first mammals with any major problems. While a dinosaur needed several hundred kilograms of food daily, just a few grams were enough for small mammals.
Today, biologists divide mammals into three subclasses:
marsupial: Kangaroo, koala, possum, wombat
Ursäuger: Anteater, Platypus
placental mammals: Human, ape, cow, cat, pig and more

Characteristics of mammals:

The following is a list of the most important characteristics of mammals. Occasionally, however, there may be exceptions to the features. Due to evolutionary adaptation to new environmental conditions, some animals have regressed some typical mammalian traits. This particularly applies to mammals with permanent residence in the water, including e.g. Dolphin and whale. Another special case is the platypus: As a so-called living fossil, it combines characteristics of different animal classes (see: bridgeheads).
brood: Intensive brood care of at least one parent is observed in almost all mammals.
flightlessness: With the exception of the bat, all mammals are flightless.
denture: Presence of teeth in the jaw.
brain: The brain of mammals is one of the most complex of living things. The neocortex is found only in mammals.
ossicles: The three ossicles hammer, anvil and stirrup reinforce incoming sounds and lead them from the eardrum into the inner ear.
warm-blooded: For equally warm animals, the body temperature is consistently at a certain temperature level.
body hairNearly all mammals have body hair (fur). In some aquatic animals, the fur has regressed.
circulation: Pulmonary circulation and systemic circulation provide for the enrichment of the blood with oxygen, as well as its distribution throughout the organism.
pulmonary respiration: Mammals absorb oxygen from the air through their lungs.
mammary glands: The suckling of the young with milk from the mammary glands is the characteristic of the mammals.
quadrupedalismEach mammal has four extremities (in humans, these are arms and legs).
Viviparie: Mammals are live, i. At birth, the cub is not in an egg in which it would still have to grow. The only exception is the platypus.
spinal column: Among the vertebrates, every mammal invariably has a spine.

List of mammals:

African Elephant, Alpaca, Anteater, Anteater, Antelope, Asian Elephant, Aurochs, Bear, Pine Marten, Bengal Cat, Bengal Tiger, Thatch Wolf, Beaver, Burmese Cat, Muskrat, Bison, Blue Whale, Bonobo, Brown Bear, White-Rhinoceros British Shorthair, Humpback whale, chinchilla, badger, fallow deer, degu, dolphin, dingo, dromedary, squirrel, polar bear, elk, elephant, aardvark, meerkat, donkey, sloth, hare, fennec, bat, flying fox, finger animal, otter, fossa, ferret, fox, Chamois, gazelle, cheetah, gibbon, giraffe, gorilla, grizzly bear, armadillo, haflinger, hare, dormouse, hamster, ermine, deer, dog, hyena, hedgehog, polecat, impala, jaguar, camel, rabbit, cat, Icelandic horse, kangaroo, Capuchin Monkey, Katta, Koala, Leprechaun, Kodiak Bear, Coyote, King Tiger, Kudu, Cow, Llama, Lemming, Lemur, Leopard, Liger, Lynx, Lion, Maine Coon, Mandrill, Manul, Mammoth, Marten, Mole, Mouse, Weasel, Guinea Pig , Mouflon, mongoose, groundhog, nudibranch, nar whale, coatis, rhino, clouded leopard, mink, hippopotamus, nutria, okapi, opossum, orangutan, orca, ocelot, panda, panther, baboon, persian cat, horse, plumploris, polar fox, sperm whale, przewalski's horse, cougar, ragdoll Cat, Rat, Reindeer, Rhesus monkey, Beef, Seal, Red panda, Ruffled tiger, Savannah cat, Sheep, Jackal, Chimpanzee, Platypus, Snow leopard, Black bear, Pig, Killer whale, Manatee, Serval, Shetland pony, Siamese cat, Siberian tiger, Dormouse, Sphynx cat, Porcupine, Capricorn, Beech marten, Skunk, Chipmunk, Tapir, Tasmanian devil, Tiger, porpoise, Squirrel monkey, Bactrian camel, Wolverine, Whale, Wallaby, Walrus, Raccoon, Water buffalo, Aquatic pig, Wild cat, Boar, European bison, Wolf , Wombat, gerbil, yak, zebra, goat, ground squirrel