This information gets passed on from generation to generation. Elephants live in a social hierarchy dominated by older females.
Females travel in long-lasting social units of about half a dozen adult females and their offspring, with the unit being led by a single older female, the matriarch. Males do not maintain long-term social bonds, remaining in the unit only into their teens.
They then live out their lives in loose bachelor groups or wandering on their own. To test the importance of the age of the female leader of the individual units, researchers from the University of Sussex, the Institute of Zoology in London and the Amboseli Elephant Research Project in Kenya used high-powered hi-fi equipment to play back the sounds of elephant calls.
Calls from complete elephant strangers prompted the mothers to cluster around their young defensively, while familiar calls were ignored. The units led by the oldest matriarchs, those with the most experience, were best able to distinguish between friends and those that might present problems by harassing calves or starting disputes.
If these key individuals cannot immediately distinguish between potential threats, their families may spend too much time being defensive and not enough time reproducing. In fact, the scientists found the age of the matriarch to be a significant predictor of the number of calves produced by the family per female reproductive year.
These findings present important implications for conservation of elephants because older, larger animals are more likely to be targets for hunters and poachers, and killing these individuals could weaken entire family units for years. An elephant can live up to 70 years and when an elephant dies of old age the cause of death is often hunger as the 6th set of molars wears out.
There are two subspecies of the African elephant, the forest elephant Loxodonta africana cyclotis and the savanna elephant Loxodonta a. There is some evidence to suggest that these may in fact be two different species but this issue is still being debated. The African forest elephant can be distinguished from the savanna elephant by its smaller body size, smaller ears, and its straighter, downward - projecting tusks.
Most of the forest elephants live in central and western Africa's rain forests while the savanna elephant is found throughout the grassy plains, woodlands, swamps and bushlands from sea level to high mountains. SSC Groups. Photo: Esther Birchmeier. Q: What are the closest relatives of elephants?
Q: Do all elephants have tusks? Q: I heard that elephants can regrow their tusks - is it true? Q: What does an elephant use its tusks for? Q:What is the full purpose of the elephant's trunk? Q: Why does an African elephant have such large ears? Q: Why is an elephant's skin so wrinkled? Q: How much do elephants drink in a day? Q: How much do elephants eat in a day? What does their diet consist of?
Q: How many hours do elephants sleep? Male tusks can grow to be seven times the weight of female tusks as they age. Those males then no longer pass on their genes for large tusks. Poole notes that even if younger, smaller males with the potential to develop large tusks remain in the population, they will not be the primary breeders given that age, body size, and musth—a frenzied, sexually charged state for male elephants during which hormone levels are elevated—determine how often and successfully a male elephant breeds with females.
Smaller tusks are not the only genetic consequence faced by elephant populations in Africa and Asia due to heavy poaching. Over several decades, researchers have documented an increase in the percentage of tuskless males and females in a number of elephant populations.
A elephant conservation plan in Uganda reported a higher-than-normal percentage of tuskless elephants in Queen Elizabeth National Park and singled out poaching as the main cause. Whereas a normal level of tusklessness in an elephant population is somewhere between 3 percent and 4 percent, according to the Ugandan report, a survey of Queen Elizabeth National Park revealed tusklessness in the elephant population to be between 9 percent and 25 percent.
For African elephants, tuskless males have a much harder time breeding and do not pass on their genes as often as tusked males. In heavily poached populations, says Poole, the ratio of tuskless animals in the population increases as poaching continues. You can see this in almost any population that has experienced a wave of heavy poaching, in Gorongosa [in Mozambique], for example, or Selous [in Tanzania].
One might go a step further and contend that wiping out elephants—be they big tuskers or not—amounts to ecological sabotage as well. In elephants, these incisors continue to grow throughout their lives, extending from deep within their upper jaw.
The tusks are one of the most noticeable features of elephants, along with their massive body size and long trunk one of the most amazing and versatile appendages in the animal world — but that is another story. In African elephants both males and females have tusks, while in Asian elephants only the males do. While our incisors are used only for biting food, elephants use theirs for a whole range of activities , from digging holes and stripping bark from trees to fighting.
Generally speaking, male elephants use their impressive size to intimidate rivals and impress females. Size is so important in attracting mates that adult males have evolved to be twice as large as adult females, reaching a whopping seven metric tonnes. This is the weight of four family cars — with passengers. As part of the package, male elephant tusks are often five to seven times as large as those of adult females. Some of the largest tusks ever recorded belonged to an old elephant called Ahmed , who lived in Kenya until the ripe old age of His tusks were 3m in length and weighed 67kg each.
That is 5kg more than the average weight of an adult human. ElephantVoices has developed eight educational modules explaining how to read and understand these characteristics, also used in the Mara Elephants Who's Who database. You should start by determining whether the elephant you are trying to identify is male or female, and will get help from How to sex African Elephants. It helps to be able to put the elephant you are trying to identify into a size category.
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