Elephant Pregnancy Facts , 2. A Big Pregnancy for a Big Animal , 3. Elephant brain facts 1 , 4. Elephant brain facts 2 , 5. An Elephant Never Forgets , 6. The Intelligence of Elephants 1 , 7.
The Intelligence of Elephants 2 , 8. Elephants Under Threat , 9. Elephant Reproduction Cycles , Unpredictable Males , The Unique Extended Pregnancy 1 , The Unique Extended Pregnancy 2 , Elephant Conservation Through Artificial Insemination , Artificial Insemination of Elephants , Early Days of a Calf 1 , Early Days of a Calf 2.
Your information will be used in accordance with our privacy policy. This education and early socialization helps a male to avoid aggressive and possibly fatal encounters in the future. A young male's growing interest for novel male rough-housing partners from other families appears to be a trigger for his departure from his natal family.
As a male grows he spends less and less time with his family. A male is considered independent when he spends less than 20 percent of his time with his natal family. The average age of independence in the Amboseli population is 14 years old, but there is a wide range, with some males leaving as early as nine and others as late as 18 years old.
An evolutionary reason for the males' departure from their family may be to avoid inbreeding and genetic research has shown that males do avoid breeding with close maternal and even paternal female relatives.
Once independent, young adult males spend the majority of their time in association with other families or mixed groups. Spermatogenesis the formation of sperm occurs at around 10 years of age, but males do not begin to produce sperm in sufficient quantities until about 17 years old. These young males show interest in estrous females, but they are only half the weight of full-grown males; their small size and low social rank render them incapable of competing successfully for access to receptive females.
They must go through an extended period of growth and social development before they are able to compete with larger, older, more experienced males.
Male elephants grow rapidly during their teen years and continue growing, though more slowly, through most of their adult lives. Since males continue to grow in height and weight throughout their lives, older males are larger and generally dominant to younger males. When a male is in his late teens or early twenties he typically comes into into musth for the first time.
Musth, a period of heightened sexual activity and aggression is defined by unique behavioral displays, swollen and secreting temporal glands, dribbling strong smelling urine and a characteristic low frequency vocalization, the musth rumble. During musth, males also have increased levels of circulating testosterone.
Musth males in the Amboseli population range from 17 to 63 years old. Young males first start entering musth around the time their rate of growth in height begins to decline, allowing them to allocate more energy into putting on the weight they need to sustain energetically costly musth periods.
It is also around this age when males have grown larger than all adult females and are therefore physically able to successfully mount an estrous female. There is a strong relationship between a male's age and his duration of musth.
The musth periods of the young males may last only a matter of days. Males between years old come into musth for slightly longer periods of time, usually for a couple of weeks in a row, and they also may come into musth several times in a longer sexually active period. But, by the time a male reaches 35 years old his sexual cycle becomes more distinct and by 40 years of age a male exhibits a well defined musth period of three to four months in duration in a predictable yearly cycle.
The length of a male's musth period increases with age until he is approximately 50 years old when it starts to decrease. Reproductive success is positively correlated with increasing age. Males attain peak reproduction between 40 and 55 years of age are still reproductively active at age 60, at that age siring as many calves as a year-old male. Males need size, strength and experience to mate successfully. Young males are usually unsuccessful for several reasons. Copulation is quite complicated for males and successful mounting is a skill that requires experience.
A male must learn the proper technique for manipulating his long, curved, mobile penis. The female reproductive tract is also long and curved and a male must first mount the female and then move his penis into the correct position while the female stands still. Females prefer older males and frequently refuse to stand for young males. In addition, young males have much shorter penises than older males and penis size is probably an additional impediment for young males to successfully impregnate females.
In addition, rank among non-musth males is determined by size and strength. A year-old male weighs half that of a year-old male. Large males frequently displace young males when they are competing for access to an estrous female and, if a young male is lucky enough to mount a female, he is most often forced down or knocked off!
However, there are cases where elephants can have twins, but this only happens in one per cent of elephant births. This is only slightly smaller compared to humans, where 1. As you can imagine, carrying two huge babies can be very dangerous for the mother. However, we do see this happening, particularly with wild African elephants. At birth, elephants can weigh up to pounds and stand about 3ft tall. Imagine the poor stork having to carry all that weight!
Elephants give birth around every four years, and given their pregnancies can last around two years, that is quite a lot! Although elephants can live for years, they typically only have about four or five babies during their lives.
However, in areas of Africa, for example, where there can be food shortages at certain times of year, elephants are typically born in the rainy season. A study on working elephants in Myanmar showed that 40 per cent of babies were born between December and March at the beginning of the dry season. A lot of the words we use for elephants are similar to those we use for cows.
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