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CLASS MAMMALIA
- includes all animals with mammary glands … |
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Mammals are
members of class
Mammalia, air-breathing vertebrate
animals
characterized by the possession of endothermy,
hair, three middle ear bones,
and mammary
glands functional in mothers with young. Most mammals also possess
sweat
glands and specialized teeth. The largest group of mammals, the placentals,
have a placenta
which feeds the offspring during gestation. The mammalian brain, with its
characteristic neocortex,
regulates endothermic
and circulatory
systems, the latter featuring red blood
cells lacking nuclei
and a four-chambered heart. Mammals range in size from the 30–40
millimeter (1- to 1.5-inch) bumblebee
bat to the 33-meter (108-foot) blue whale.
The word "mammal" is modern, from the scientific name Mammalia coined by Carl Linnaeus in 1758, derived from the Latin mamma ("teat, pap"). All female mammals nurse their young with milk, which is secreted from special glands, the mammary glands. |
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Except
for the five species of monotremes (which lay eggs), all living mammals give birth to
live young. Most mammals, including the six most species-rich orders, belong to
the placental
group. The three largest orders, in descending order, are Rodentia (mice, rats, porcupines, beavers, capybaras, and other
gnawing mammals), Chiroptera
(bats), and Soricomorpha
(shrews, moles
and solenodons).
The next three largest orders, depending on the classification
scheme used, are the primates, to which the human species belongs, the
Cetartiodactyla
(including the even-toed hoofed mammals and the whales), and the Carnivora (cats, dogs, weasels, bears, seals, and their
relatives).
Quick Facts on Mammals
Quick Facts on Mammals
1.
Mammals are animals that have skin covered with
hair.
2. Mammals
are viviparous – young are born alive.
3. Mother
mammals nourish their babies with milk thru
mammary glands.
mammary glands.
4. Mammals
are heterodonts – have a variety of specialized
teeth (incisors, canines, premolars, and molars) and strong
jaws.
teeth (incisors, canines, premolars, and molars) and strong
jaws.
5. Most
mammals are placental – the embryo develops internally
in a uterus to the mother by a placenta.
in a uterus to the mother by a placenta.
6. Some are
marsupial – in the very early part of the embryonic
development the young are born and completes its development in the mother’s pouch
development the young are born and completes its development in the mother’s pouch
7. One very
unusual is the duck-billed platypus is monotreme –its egg laying.
8. Many
mammals are terrestrial.
9. Others
are aquatic.
10.
A few are aerial.
11.
Some are domesticated.
12.
Others are wild.
13.
Mammals are the only animals with an outer ear
just like the hare.
14.
Pandas eat lots of bamboo up to 12 hours every day.
15.
Moose are the biggest of all the deer.
16.
Despite the hump, a camel’s spine is straight.
17.
Porcupines float in water.
18.
A cat’s jaws cannot move sideway
19.
Koala sleeps 20 hours each day.
20.
Bats are the only flying mammals.
21.
Kangaroos cannot walk backwards.
22.
Chimps are the only animals that can recognize
themselves in a mirror.
23.
Elephants have been known to remain standing when
they die.
24.
Giraffes are the tallest animals.
25.
Cheetahs are the fastest animals.
26.
A zebra is white with black stripes.
27.
Armadillos can walk underwater.
28.
Blue whale is the largest animal that lived on
earth.
29.
Only humans can sleep on their backs.
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