Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are an informal grouping within the proboscidean family Elephantidae.
The mystery of the elephant's long pregnancy has been unravelled by scientists. A quirk of biology allows the unborn calf to develop in the womb for almost two years, giving it the brain power it needs to survive from birth.
At up to 23 months, elephants boast the longest gestation period of any land animal. They also boast big babies: a newborn elephant weighs about 230 pounds (105 kilograms).
Mums are pregnant for a long time
While carrying a baby for nine months may seem like long enough for some human mothers, spare a thought for giraffes who have gestation periods of 15 months!
The shortest known gestation is that of the Virginian opossum, about 12 days, and the longest that of the Indian elephant, about 22 months. In the course of evolution the duration of gestation has become adapted to the needs of the species.
Bullfrogs… No rest for the Bullfrog. The bullfrog was chosen as an animal that doesn't sleep because when tested for responsiveness by being shocked, it had the same reaction whether awake or resting.
The boa constrictor, monitor lizard and Komodo dragon are both capable of becoming pregnant without male fertilization, by parthenogenesis.
Gestation in lions is about 110 days and mean litter size is 2.3 (Schaller 1972). Females cease lactation when their cubs are 5-8 mo old (Schaller 1972), but do not resume sexual activity until their cubs are about 18 mo old (Bertram 1975; Packer and Pusey 1983).
Being 13-18 weeks in length, the elephant estrous cycle is the longest amongst all studied non-seasonal mammals to date. Progesterone increases 1-3 days after ovulation, indicating the start of the luteal phase, which lasts 6-12 weeks.
Answer. The males usually die soon after the fertilisation of the egg and females live long enough to produce the young ones.
Elephants are capable of having twins. However, the percentage of twin births is fairly low. Only one percent of elephant pregnancies result in twins. It is hypothesized that this reason is that mother elephants do not have enough milk to keep two elephants alive—the likelihood of both calves surviving decreases.
"In captive elephants it is common for them not to know about looking after their young." She may also have gone through birth without another female to help and comfort her. Elephants in zoos have been known to intentionally kill their young, but there is only speculation as to why this is.
"Male lions “mating” with other males is not an altogether uncommon occurrence," the told Traveller24. "This behaviour is often seen as a way of asserting dominance over another male, or a way of reinforcing their social bonds. Lions' social structures can be a complex system," he says.
A single male might often not be in control for long enough to mate with his grown daughters. Females do not only mate with the leader of their pride, but mate sometimes with males from outside of the pride.
Researchers say captive animals breed with kin 73 per cent of the time. Contrary to what many scientists had assumed, animals — when given a choice — rarely avoid mating with their cousins or siblings, according to a new study published in the journal Nature Ecology & Evolution.
Probably not. Ethical considerations preclude definitive research on the subject, but it's safe to say that human DNA has become so different from that of other animals that interbreeding would likely be impossible.
So, while it's possible for a human baby to be born of a virgin mother, it's very, very unlikely: These two genetic deletions might each have a one in 1 billion chance of occurring, and that's not counting the calcium spike and division problem required to initiate parthenogenesis in the first place.
Baby mice have been made with two mums and no dad, say researchers at the Chinese Academy of Sciences. It took a substantial feat of genetic engineering to break the rules of reproduction. The scientists said the "bimaternal" (two mammas) animals were healthy and went on to have pups of their own.