Mammal Characteristics

Mammals are the most developed animals on planet earth, they are generally terrestrial, and there are some mammals that can fly (but without feathers).

Most mammals are viviparous and all mammals are vertebrate animals.

One of the characteristics of mammals is that its classification is very broad and it must be clarified that sub-classifications are derived from the main classification.

Characteristics of mammals:

1.- Definition.- Mammals are known as all those animals that suck their first food from the mammary glands of their mothers, it is known that the Mammals' first lactation is highly nutritious and contains so-called "colostrum", which are special antibodies to kids. All mammals are animals with a skeletal system, although their structure varies according to the species and subspecies, as the case may be; These animals are usually born without teeth, and they develop them later, a natural function that is made to protect the mother from injury. The suction is instinctive, and it is a mixed process between the palate, the lower and the lips.

2.- Reproduction.- In this sense, it must be clarified that there are three forms of reproduction, although all are reproductions by opposite gametes (male and female):

• Viviparous reproduction
• Viviparous reproduction without placenta
• Oviparous reproduction

3.- Habitat.- Mammals inhabit all the means of the pane, aquatic, terrestrial and aerial, and this depends on the division or classification in which they are found.

4.- Classification.- The classification is somewhat extensive, but simple, it begins with a division between Prototeria and terrestrial (Terrios), to this division three more divisions are applied, which are the most extensive.

• Prototories
• Metaterios and
• Euterios

It is around this division that the complete classification is developed.

Complete classification of mammals:

a) Prototheiries.- They are mammalian animals that have their reproduction in the oviparous way, they are characterized by having a beak and being Amphibian animals are very rare in the world, their diet is based on crustaceans, worms and insects

• Echidna
• Platypus

b) Metaterios.- These are viviparous animals, which do not have a placenta, there are few species that have these qualities:

• Kangaroos
• Koalas
• Uombat
• Bandicut

c) Euterios.- This classification is the most abundant, and in this segment there is a subdivision of ten variants, being here the human being, which for obvious reasons is considered the most evolved.

1. Tubulidentate and xenatros.- These are mammals that have a poor formation of their teeth.
   - Armadillo
   - Anteater
   - Lazy
2. Hiracoids, lagomorphs, rodents.- They are herbivorous animals, they do not have canine teeth (fangs), and their incisor teeth are very sharp, of continuous growth, they are characterized by being able to gnaw hard food and materials solid.
   - Chipmunk
   - Beaver
   - Rabbit
   - Groundhog
   - rat
   - Mouse etc.
3. Ungulates.- They are herbivorous and omnivorous animals, if they have fangs they are defensive and extremely large, useless for feeding, and outside of the pachyderms, they lack canines.
   - Bovids
   - Elephants
   - Equines
   - Tilopods
4. Cetaceans.- These animals live in water, have lung respiration and developed fins instead of hands, which are perfected for movement in the water.
   - Whale
   - Sperm whale
   - Dolphin
   - Porpoise
5. Sirenids.- They are herbivorous animals, aquatic life and lung respiration, their diet is carnivorous, eating fish and some crustaceans.
   - Sea cow
   - Seal
   - Walrus
6. Fisipeds.- These are carnivorous animals, with fangs, claws and nails, they usually hunt their food although there are scavengers, their rear teeth are shaped like blades, developed to cut meat.
   - Canids
   - Felines
   - Mustelids
7. Pinnipeds.- These are carnivorous animals, their teeth are similar to fisipeds, and their habitat is aquatic, they have fins but they live on the surface of ice and on beaches.
   - Seal
   - Walrus
   - Elephant seal
8. Dermoptera, folidotes, Insectivores.- These animals feed on insects and worms, their molars are pointed and their nails with tips are developed.
   - Caguan
   - Sea urchin
   - Shrew
   - Mole
9. Chiroptera.- They are the only flying mammals that are known, they feed on fruits and insects, their reproduction is viviparous and their habitat is usually in caves.
   - Bat
   - Vampire
   - Flying fox
10. Primates.- These animals are considered the most developed, they are omnivores, they have complete teeth, with incisors (fangs) and teeth to grind, their hands are prehensile and plantigrade.
    - Chimpanzee
    - Gorillas
    - Humans
    - Orangutan
    - Apes Etc.

Internal organs that mammals have

The organs of these animals have many similarities, and they have essential functions for life and their metabolism. Although many are shared with other animals, there are many that are unique to mammals.

• Kidneys
• Heart
• Liver
• Blood vessel
• Pancreas
• Small intestine
• Large intestine
• Lungs
• Bladder
• Stomach
• Brain
• Esophagus
• Lips
• Mouth
• Language
• Nasal or respiratory system
• Eyes (although in insectivores, dermopterans and flidotes they are poorly developed),
• Nose
• Ears