Heartbeat: A comparison between the heart-beat of man, mouse and elephant. Smallest mammals have faster heart beats than larger ones. Males are highly individualistic and only join the herd for mating seasons. Their penis is retractable, there is no scrotum and the testicles are housed internally.
Males duel each other with the winner claiming steed rights for the whole herd. Deaths sometimes occur from wounds inflicted in these duels. The female runs away coyly for a short while, as part of a ritual, before submitting to her victorious mate. The bull then mounts the female from behind gripping her body with his fore feet upon her pelvis and assumes a standing posture. Copulation takes around 20 seconds with very little movement or noise.
Mating continues promiscuously with other herd males , for two days after which the most powerful bull drives off the others. He then remains with the cow for around three weeks. The female, when pregnant, carries the calf for 22 months and when parturition birth occurs other herd cows form a circle around the pregnant cow.
She assumes a squatting position while giving birth and the birth takes around 2 hours. In regions where large carnivores, such as big cats, prey upon newly born animals the mother forms alliances with other herd members. Mother and associated protectors then blow dust over the new-born calf with their trunks in order to dry it. Trunks Arguably the most versatile of all animal organs. The trunk can be used for such diverse tasks as shifting a kg log to picking up a coin.
It is a boneless mass of flesh and up to , muscles that can bend easily. It is 2 metres long and weighs around kg. The trunk has a small finger like lip at the end which can distinguish between size, shape, texture, hot and cold.
When totally submerged in water the trunk can also be used as a snorkel. Trunks can hold six litres of water and are often used as a flexible shower hose pipe. It is a superb organ of smell, and can be directed easily toward the source.
By beating the ground violently with the trunk the elephant signals its anger or displeasure. This emotion equates to desk-banging in humans. When an elephant is on unsteady or unfamiliar ground it will use the outside of the trunk to beat the earth, determining if the ground is firm enough to walk on. Once safety is substantiated the front foot is moved forward onto the tested area.
Elephants are non-ruminant herbivores. They do not chew cud, ruminate or belch as ruminant animals e. Properly equipped, a car could travel 20 miles on the amount of methane produced by one elephant in a single day.
Elephants may feed for up to 16 hours a day. In the wild one animal can consume as much as pounds of food in a single day, although — pounds is a more typical amount. In a zoo, a typical adult elephant may eat bales of hay and 10 — 18 pounds, or 4.
This amounts to a yearly quantity of more than 29, kg of hay and kg of feed per animal,. An elephant defecates from 12 to 15 times a day, a daily quantity of — pounds. This adds up to a yearly quantity of over 85, pounds of manure, more than 40 tons, per adult elephant. Generally, the size of the ears is directly related to the amount of heat dissipated through them. The difference in ear size between African and Asian elephants can be based on their geographic range.
The African elephant usually lives in a hotter, sunnier climate than the Asian elephant and needs larger ears to aid in thermoregulation. Although ears help to regulate body temperature in both species, they are more effective in African elephants in that regard because the ears are larger.
Flapping the ears helps to cool an elephant in two ways. The hotter it is the faster the elephants will flap its ears. On a windy day, however, an elephant may find it easier to simply stand facing into the wind and hold its ears outward to take advantage of the breeze.
An elephant may also spray water on its ears, which also will cool down the blood before it returns to the rest of the body. The ears of an African elephant are enormous. Each ear is about six feet from top to bottom and five feet across. A single ear may weigh as much as one hundred pounds. When an elephant is angry or feels threatened, it may respond by spreading its ears wide and facing whatever it may perceive as a threat.
Both are born with small brain masses. Similar to a human being, there is considerable growth and development in the brain as a young elephant grows up. As the mass of the brain increases so does the learning ability of young elephants. Brain size provides a rough measure of mental flexibility; large mammalian brains are associated with superior intelligence and complex social behavior.
The small and large intestines may reach a combined length of 35m. As food works its way through this system, it can take 24 hours to digest a meal. Elephants take about breaths per minute when lying or very calm. This increases to 10 breaths per minute when standing or active at rest humans take between breaths per minute.
The lungs attach directly to the chest cavity and to the diaphragm. Unlike other animals which use pressure changes to breathe in and out , elephants use muscles to inflate and deflate their lungs.
Due to their large size elephants reproduce slowly. First conception typically occurs at 10 - 11 years with the interval between calves ranging from 4 - 9 years. Elephant cows come into oestrous for periods of days and will tend to try to avoid approaching bulls. Bull elephants usually come into musth once a year for a period lasting a few days to several months.
During musth, testosterone levels rise, bulls become very aggressive and are more sexually active. Musth bulls can easily be identified by the copious secretion of fluid from the temporal gland on the side of their head and the constant dribble of a pungent greenish liquid from their penis. Cows may be approached by several bulls who may fight over her. Any musth bulls will dominate other potential suitors. When a bull finds a potential mate he will use his trunk to test her urine or vulva to see whether she is ready to mate.
A receptive cow may walk or even run away from the herd if approached. When a bull finally gets close enough, copulation, with the bull standing on his hind legs, takes less than a minute. The bull guards the female against the approach of other males and this protective behaviour can last for a few hours or even several days.
Mating and births are most frequent during the rainy season. Births take place with the female squatting. Delivery is relatively quick about half a minute and the newborn is helped onto its feet by its mother and other females.
New born calves weigh about kg and are very feeble for the first few days. They remain shaky for several weeks. The young calf has to locate the teats between the mother's forelegs on its own. While suckling, the trunk hangs to one side. Calves begin trying food other than milk at about 4 months, but are not capable of feeding themselves on solid food until well into their second year. Suckling carries on until the birth of the next calf, which can be up to 8 years.
Before young cows have their own calves they are the main caretakers of other calves within the herd. Known as "allmothers" they will rush to protect or assist any calf in trouble and give comfort to distressed calves.
Calves with a greater number of allmothers have a higher survival rate. Many elephants die from natural causes. Just like humans, they can suffer from life-threatening diseases or abnormalities. They can be affected by environmental conditions such as drought. And they may sustain fatal injuries through accidents or fights with other individuals. Even if elephants lead a long and healthy life, they will finally die of starvation when their teeth can no longer function.
Scroll down to find out more about elephant mortality, or click on a specific link below:. Serious drought conditions can cause elephant deaths. Unlike their younger brothers or sisters, they are no longer able to suckle from their mother. In , 9, elephants starved to death in a severe drought in Tsavo National Park, Kenya. In , several months of drought conditions in Hwange National Park in Zimbabwe caused severe water shortages. Grazing was scarce, waterholes dried up and at least 40 elephants died from starvation and dehydration.
Elephants are relatively free from most fatal diseases. They may die from blood diseases such as septicemia contracted from infected wounds or after childbirth. They are also susceptible to anthrax, tuberculosis, and foot and mouth disease.
In , anthrax outbreaks in the eastern Caprivi region of Namibia and Chobe National Park in Botswana both caused a number of elephant deaths. Anthrax is a bacterial infection contracted through direct contact with infected carcasses or inhalation of anthrax spores.
It causes bleeding from the mouth and other body openings and death is sudden. Due to their longevity, older elephants also suffer from conditions associated with old age such as cardiovascular disease.
They are liable to heart attacks and strokes. Potentially one of the largest living animals on earth, the elephant can live for 65 years or more. The limiting factor for its life expectation is the condition of its teeth. Once its final set of molars has been warn down, the elephant loses the ability to grind and adequately digest the large quantities of coarse vegetation that make up the bulk of his diet. It eventually succumbs to the effects of malnutrition and dies.
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