African elephants are members of the genus Loxodonta comprising two living elephant species, the African bush elephant ( L. africana) and the smaller African forest elephant ( L. cyclotis). Both are social with grey skin. However, they differ in the size and colour of their as well as the shape and size of their and .
Both species are at a pertinent risk of extinction according to the IUCN Red List; as of 2021, the bush elephant is considered endangered while the forest elephant is considered critically endangered. They are threatened by habitat loss and fragmentation, along with poaching for the illegal ivory trade in several range countries.
Loxodonta is one of two extant genera in the family Elephantidae. The name refers to the lozenge-shaped enamel of their molar teeth. Fossil remains of Loxodonta species have been found in Africa, spanning from the Late Miocene (from around 7–6 million years ago) onwards.
Elephas ( Loxodonta) cyclotis was proposed by Paul Matschie in 1900, who described three African elephant zoological specimens from Cameroon whose differed in shape from those of elephant skulls collected elsewhere in Africa. In 1936, Glover Morrill Allen considered this elephant to be a distinct species and called it the 'forest elephant'; later authors considered it to be a subspecies. Morphological and genetic analyses have since provided evidence for species-level differences between the African bush elephant and the African forest elephant.
In 1907, Richard Lydekker proposed six African elephant subspecies based on the different sizes and shapes of their ears. They are all considered synonymous with the African bush elephant.
A third species, the West African elephant, has also been proposed but needs confirmation. It is thought that this lineage has been isolated from the others for 2.4 million years.
The oldest species of Loxodonta known is Loxodonta cookei, with remains of the species known from around 7–5 million years ago, from remains found in Chad, Kenya, Uganda, and South Africa.
Analysis of nuclear DNA sequences indicates that the genetic divergence between African bush and forest elephants dates 2.6 – 5.6 million years ago. The African forest elephant was found to have a high degree of genetic diversity, likely reflecting periodic fragmentation of their habitat during the changes in the Pleistocene.
Gene flow between the two African elephant species was examined at 21 locations. The analysis revealed that several African bush elephants carried mitochondrial DNA of African forest elephants, indicating they hybridised in the savanna-forest transition zone in ancient times. However, despite the hybridisation at the contact zone between the two species, there appears to have been little effective gene flow between the two species since their initial split.
DNA from the European straight-tusked elephant ( Palaeoloxodon antiquus) indicates that the extinct elephant genus Palaeoloxodon is more closely related to African elephants than to Asian elephants or mammoths. Analysis of the genome of P. antiquus also shows that Palaeloxodon extensively hybridised with African forest elephants, with the mitochondrial genome and over 30% of the nuclear genome of P. antiquus deriving from L. cyclotis. This ancestry is closer to modern west African populations than to central African populations of forest elephants. Analysis of Chinese Palaeoloxodon mitogenomes suggests that this forest elephant ancestry was widely shared among Palaeoloxodon species.
When separate family units bond, they form kinship or bond groups. After puberty, male elephants tend to form close alliances with other males. While females are the most active members of African elephant groups, both male and female elephants are capable of distinguishing between hundreds of different low-frequency infrasonic calls to communicate with and identify each other.
Elephants use some vocalisations that are beyond the hearing range of humans, to communicate across large distances. Elephant mating rituals include the gentle entwining of trunks.
Bulls were believed to be solitary animals, becoming independent once reaching maturity. New research suggests that bulls maintain ecological knowledge for the herd, facilitating survival when searching for food and water, which also benefits the young bulls who associate with them. Bulls only return to the herd to breed or to socialize; they do not provide parental care to their offspring or raise them, but rather play a fatherly role in general to younger bulls to show dominance.
Elephants exhibit a wide variety of behaviours, including those associated with grief, learning, mimicry, art, play, a sense of humor, altruism, use of tools, compassion, cooperation, self-awareness, memory and possibly language. All of these behaviors point to a highly intelligent species that is thought to be equal to cetaceans and .
The African elephant's cognitive complexity includes behaviors indicative of empathy, problem-solving, and cooperative group behaviors. These traits underscore the evolutionary convergence of intelligence across species, similar to that seen in primates and cetaceans.
Post sexual maturity, males begin to experience musth, a physical and behavioral condition that is characterized by elevated testosterone, aggression and more sexual activity. Musth also serves a purpose of calling attention to the females that they are of good quality, and it cannot be mimicked as certain calls or noises may be. Males sire few offspring in periods when they are not in musth. During the middle of estrus, female elephants look for males in musth to guard them. The females will yell, in a loud, low way to attract males from far away. Male elephants can also smell the hormones of a female ready for breeding. This leads males to compete with each other to mate, which results in the females mating with older, healthier males. Females choose to a point who they mate with, since they are the ones who try to get males to compete to guard them. However, females are not guarded in the early and late stages of estrus, which may permit mating by younger males not in musth.
Males over the age of 25 compete strongly for females in estrus, and are more successful the larger and more aggressive they are. Bigger males tend to sire bigger offspring. Wild males begin breeding in their thirties when they are at a size and weight that is competitive with other adult males. Male reproductive success is maximal in mid-adulthood and then begins to decline. However, this can depend on the ranking of the male within their group, as higher-ranking males maintain a higher rate of reproduction. Most observed matings are by males in musth over 35 years of age. Twenty-two long observations showed that age and musth are extremely important factors; "… older males had markedly elevated paternity success compared with younger males, suggesting the possibility of sexual selection for longevity in this species."
Based on vegetation types that provide suitable habitat for African elephants, it was estimated that in the early 19th century a maximum of 26,913,000 African elephants might have been present from the Sahel in the north to the Highveld in the south. Decrease of suitable habitat was the major cause for the decline of elephant populations until the 1950s. Hunting African elephants for the ivory trade accelerated the decline from the 1970s onwards. The carrying capacity of remaining suitable habitats was estimated at 8,985,000 elephants at most by 1987.
In the 1970s and 1980s, the price of ivory rose, and poaching for ivory increased, particularly in Central African range countries where access to elephant habitats was facilitated by logging and petroleum mining industries.
Between 1976 and 1980, about raw ivory was exported from Africa to Hong Kong and Japan, equivalent to tusks of about 222,000 African elephants.
The first continental elephant census was carried out in 1976. At the time, 1.34 million elephants were estimated to range over .
In the 1980s, it was difficult to carry out systematic surveys in several East African range countries due to .
In 1987, it was estimated that the African elephant population had declined to 760,000 individuals. In 1989, only 608,000 African elephants were estimated to have survived.
In 1989, the Kenyan Wildlife Service burned a stockpile of tusks in protest against the ivory trade.
When the international ivory trade reopened in 2006, the demand and price for ivory increased in Asia. In Chad's Zakouma National Park, more than 3,200 elephants were killed between 2005 and 2010. The park did not have sufficient guards to combat poaching and their weapons were outdated. Well organized networks facilitated smuggling the ivory through Sudan.
The government of Tanzania estimated that more than 85,000 elephants were lost to poaching in Tanzania between 2009 and 2014, representing a 60% loss.
In 2012, a large upsurge in ivory poaching was reported, with about 70% of the product flowing to China.
China was the biggest market for poached ivory but announced that it would phase out the legal domestic manufacture and sale of ivory products in May 2015.
Conflicts between elephants and a growing human population are a major issue in elephant conservation. Human encroachment into natural areas where bush elephants occur or their increasing presence in adjacent areas has spurred research into methods of safely driving groups of elephants away from humans. Playback of the recorded sounds of angry Western honey bees has been found to be remarkably effective at prompting elephants to flee an area. Farmers have tried scaring elephants away by more aggressive means such as fire or the use of chili peppers along fences to protect their crops.
In 1989, the Convention on International Trade in Endangered Species of Wild Fauna and Flora listed the African elephant on CITES Appendix I. This listing banned international trade of African elephants and their body parts by countries that signed the CITES agreement. Hunting elephants is banned in the Central African Republic, Democratic Republic of Congo, Gabon, Côte d'Ivoire, and Senegal. After the ban came into force in 1990, retail sales of in South Africa have plummeted by more than 95% within 10 years.
As a result of the trade ban, African elephant populations recovered in range countries.
The African Elephant Specialist Group has set up a Human-Elephant Conflict Task Force with the aim to develop conflict mitigation strategies.
In 2005, the West African Elephant Memorandum of Understanding was signed by 12 West African countries. The Convention on the Conservation of Migratory Species of Wild Animals provided financial support for four years to implement the West African Elephant Conservation Strategy, which forms the central component of this intergovernmental treaty.
In 2019, the export of wild African elephants to zoos around the world was banned, with an exception added by the EU to allow export in "exceptional cases where … it is considered that a transfer to ex-situ locations will provide demonstrable in-situ conservation benefits for African elephants". Previously, export had been allowed in Southern Africa with Zimbabwe capturing and exporting more than 100 baby elephants to Chinese zoos since 2012.
It was found that elephant conservation does not pose a trade-off with climate change mitigation. Although animals typically cause a reduction of woody biomass and therewith above-ground carbon, they foster soil carbon sequestration.
South Africa uses elephant tusks in their coat of arms to represent wisdom, strength, moderation and eternity.
In the western African Kingdom of Dahomey (now Benin), the elephant was associated with the 19th century rulers of the Fon people, Guezo and his son Glele. The animal is believed to evoke strength, royal legacy, and enduring memory as related by the proverbs: " There where the elephant passes in the forest, one knows" and " The animal steps on the ground, but the elephant steps down with strength." Their flag depicted an elephant wearing a royal crown.
Extinct African elephants
Phylogeny and evolution
Description
Skin, ears, and trunk
Tusks and molars
Size
Distribution and habitat
Behavior and ecology
Sleeping pattern
Family
Feeding
Intelligence
Reproduction
Threats
Conservation
In culture
As national symbols
See also
Notes
External links
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