African and Indian Elephants are the only proboscideans (Order
Proboscidea) alive today, but there is a vast number of different
species in the order that are now extinct. There are also many cases of
parallel and convergent evolution. The closest living relatives of the
modern-day elephant are in fact the dassie, or hyrax, and sea cows:
manatees and dugongs. Sea cows and dassies are thought to have evolved
from a common ancestor to the Proboscidae.
The earliest known ancestors to the elephant were
herbivores that lived about 40 million years ago, and were roughly the
sizes of pigs and cows. The direct ancestor to the modern-day elephant
is unknown, but fossils of numerous evolutionary off-shoots, such as the
moerithenes (40 million years ago), the barythenes (40 to 35 million
years ago), paleomastodons (40 million years ago), gomphotheres such as
the mastodon, the stegodon, and the mammoth have all been found and
studied.
ElephantStory
Because Elephant is Important
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วันพฤหัสบดีที่ 16 มกราคม พ.ศ. 2557
ELEPHANT ADAPTATION
The elephant has several adaptations that help it survive in its natural
habitat. To stay comfortable in the heat, an elephant can flap its
ears and create a cooling effect. The large molars in the elephant's
mouth are used for chewing and grinding very fibrous plant materials.
An elephant's trunk has many uses including picking up food, drinking
water, and communicating with other elephants. Elephants also have very
low-pitched sounds that allow them to communicate with each other.
ELEPHANT AND ECOSYSTEM
Elephants are a very important part of the ecosystems they inhabit. By
dropping seeds with their dung, they are helping to create new plant
life. Their large bodies can also knock down small trees and other
obstacles so that smaller animals can get through to find food. If
there is some kind of water drought, elephants will dig to find water
deep beneath the ground surface.
ELEPHANT FAMILY LIFE
Elephants are very family-centered animals. They travel together under
the supervision of a female called a matriarch. The matriarch of a herd
has knowledge of food and water sources and is responsible for helping
her sisters, cousins, and other family members to stay safe and healthy.
When it's time to reproduce, the female elephants mate with bull
elephants after a period of courtship. The female stays pregnant for 22
months while her baby elephant grows and develops inside of her.
During labor, the pregnant elephant is given help by another female
elephant. Once a baby elephant is born, it may drink its mother's milk
for up to four years and will be cared for by everyone in its herd.
ELEPHANT AND SOCIETY
Elephants have had a number of key places in society. Asian elephants
have been used as work animals for many years and often haul heavy loads
from one place to another. They have been also used as a method of
transportation in Asian and African countries. Some elephants are taken
out of Asia and Africa to travel with the circus and provide
entertainment. Still others are used for their tusks so that ivory
products can be made. Other members of society have revered elephants
and worked to protect them from harm.
THE DIFFERENCE BETWEEN ASIAN AND AFRICAN ELEPHANTS
To the untrained eye, African and Asian elephants can be
indistinguishable, but there are key physical features that make these
two species relatively easy to tell apart.
The most noticeable physical differences can be seen in the ears, tusks and head shapes of the two species, according to The Elephant Sanctuary, a natural-habitat refuge for endangered elephants located in Hohenwald, Tenn.
African elephants have large ears, shaped much like the continent of Africa itself. The larger surface area of their ears helps to keep African elephants cool in the blazing African sun. Asian elephants have less to worry about heat-wise, as they tend to live in cool jungle areas, so their ears are smaller.
Asian and African elephants have very distinct head shapes. African elephants have fuller, more rounded heads, and the top of their head is a single dome. Asian elephants have a twin domed head with an indent in the middle.
There's another thing sets them apart: Only male Asian elephants grow tusks and even then, not all males will have them. In African elephants, both sexes generally (but not always) exhibit tusks.
Beyond these larger, more noticeable details, there are many other, smaller features that distinguish the two elephant species: number of toenails, how wrinkled their skin is, the feel of their trunk, and even the shape of their teeth.
Despite these physical differences, both species of elephant are very similar socially. Both species of elephant are herd animals living within defined social structures, according to the conservation group WWF. The herds are usually led by the oldest female, and are made up of her daughters, sisters and their offspring. Once they reach puberty, male calves leave the mother's herd and join other young males in bachelor groups. Older males tend to be solitary.
As Asian and African elephants do not come in contact in the wild, there has only been one incident of cross-breeding between the two species. In 1978, at the Chester Zoo in England, the Asian elephant cow Sheba gave birth to a calf with an African elephant bull named Jumbolino. Their calf was named Motty, who had features of both his parents. Sadly he was premature and died of stomach complications two weeks later, according to Dr. Derek Lyon, veterinarian in charge at Chester Zoo during Motty's birth..
The most noticeable physical differences can be seen in the ears, tusks and head shapes of the two species, according to The Elephant Sanctuary, a natural-habitat refuge for endangered elephants located in Hohenwald, Tenn.
African elephants have large ears, shaped much like the continent of Africa itself. The larger surface area of their ears helps to keep African elephants cool in the blazing African sun. Asian elephants have less to worry about heat-wise, as they tend to live in cool jungle areas, so their ears are smaller.
Asian and African elephants have very distinct head shapes. African elephants have fuller, more rounded heads, and the top of their head is a single dome. Asian elephants have a twin domed head with an indent in the middle.
There's another thing sets them apart: Only male Asian elephants grow tusks and even then, not all males will have them. In African elephants, both sexes generally (but not always) exhibit tusks.
Beyond these larger, more noticeable details, there are many other, smaller features that distinguish the two elephant species: number of toenails, how wrinkled their skin is, the feel of their trunk, and even the shape of their teeth.
Despite these physical differences, both species of elephant are very similar socially. Both species of elephant are herd animals living within defined social structures, according to the conservation group WWF. The herds are usually led by the oldest female, and are made up of her daughters, sisters and their offspring. Once they reach puberty, male calves leave the mother's herd and join other young males in bachelor groups. Older males tend to be solitary.
As Asian and African elephants do not come in contact in the wild, there has only been one incident of cross-breeding between the two species. In 1978, at the Chester Zoo in England, the Asian elephant cow Sheba gave birth to a calf with an African elephant bull named Jumbolino. Their calf was named Motty, who had features of both his parents. Sadly he was premature and died of stomach complications two weeks later, according to Dr. Derek Lyon, veterinarian in charge at Chester Zoo during Motty's birth..
WHAT IS ELEPHANT?
Elephants are large mammals of the family Elephantidae and the order Proboscidea. Traditionally, two species are recognised, the African elephant (Loxodonta africana) and the Asian elephant (Elephas maximus), although some evidence suggests that African bush elephants and African forest elephants are separate species (L. africana and L. cyclotis respectively). Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia. Elephantidae are the only surviving family of the order Proboscidea; other, now extinct, families of the order include mammoths and mastodons. The largest living terrestrial animals,
male African elephants can reach a height of 4 m (13 ft) and weigh
7,000 kg (15,000 lb). All elephants have several distinctive features
the most notable of which is a long proboscis or trunk used for many purposes, particularly for grasping objects. In addition to their trunks, their incisors
grow into tusks, which serve as tools for moving objects and digging
and as weapons for fighting. The elephant's large ear flaps help to
control the temperature of its body. African elephants have larger ears
and concave backs while Asian elephants have smaller ears and convex or
level backs.
Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts and marshes. They prefer to stay near water. They are considered to be keystone species due to their impact on their environments.
Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts and marshes. They prefer to stay near water. They are considered to be keystone species due to their impact on their environments.
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