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A proboscis ( / p r oʊ ˈ b ɒ s ɪ s , - k ɪ s / ) is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate . In invertebrates, the term usually refers to tubular mouthparts used for feeding and sucking. In vertebrates, a proboscis is an elongated nose or snout.

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67-498: Gelfand is a surname meaning " elephant " in the Yiddish language and may refer to: People: Alan Gelfand , the inventor of the ollie, a skateboarding move Alan E. Gelfand , a statistician Boris Gelfand , a chess grandmaster Israel Gelfand , a mathematician, Mikhail Gelfand , a molecular biologist and bioinformacisist, a grandson of Israel Gelfand Vladimir Gelfand ,

134-634: A Soviet-Jewish writer Notions in mathematics (named after Israel Gelfand ): the Gelfand representation , in mathematics, allows a complete characterization of commutative C*-algebras as algebras of continuous complex-valued functions the Gelfand–Naimark–Segal construction the Gelfand–Naimark theorem the Gelfand–Mazur theorem a Gelfand pair , a pair ( G , K ) consisting of

201-409: A Y. The female's clitoris may be 40 cm (16 in). The vulva is found lower than in other herbivores, between the hind legs instead of under the tail. Determining pregnancy status can be difficult due to the animal's large belly. The female's mammary glands occupy the space between the front legs, which puts the suckling calf within reach of the female's trunk. Elephants have a unique organ,

268-421: A constant body temperature as well as in communication. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears and convex or level backs. Elephants are scattered throughout sub-Saharan Africa , South Asia, and Southeast Asia and are found in different habitats, including savannahs , forests, deserts, and marshes . They are herbivorous , and they stay near water when it

335-449: A day. Elephants tend to stay near water sources. They have morning, afternoon, and nighttime feeding sessions. At midday, elephants rest under trees and may doze off while standing. Sleeping occurs at night while the animal is lying down. Elephants average 3–4 hours of sleep per day. Both males and family groups typically move no more than 20 km (12 mi) a day, but distances as far as 180 km (112 mi) have been recorded in

402-504: A faster gait similar to running. In walking, the legs act as pendulums, with the hips and shoulders moving up and down while the foot is planted on the ground. The fast gait does not meet all the criteria of running, since there is no point where all the feet are off the ground, although the elephant uses its legs much like other running animals, and can move faster by quickening its stride. Fast-moving elephants appear to 'run' with their front legs, but 'walk' with their hind legs and can reach

469-494: A human brain. It is the largest of all terrestrial mammals. While the elephant brain is larger overall, it is proportionally smaller than the human brain . At birth, an elephant's brain already weighs 30–40% of its adult weight. The cerebrum and cerebellum are well developed, and the temporal lobes are so large that they bulge out laterally. Their temporal lobes are proportionally larger than those of other animals, including humans. The throat of an elephant appears to contain

536-416: A locally compact unimodular group G and a compact subgroup K a Gelfand triple , a construction designed to link the distribution (test function) and square-integrable aspects of functional analysis See also [ edit ] Gelfond Helfand Helfant [REDACTED] Surname list This page lists people with the surname Gelfant . If an internal link intending to refer to

603-548: A pouch where it can store water for later use. The larynx of the elephant is the largest known among mammals. The vocal folds are anchored close to the epiglottis base. When comparing an elephant's vocal folds to those of a human, an elephant's are proportionally longer, thicker, with a greater cross-sectional area. In addition, they are located further up the vocal tract with an acute slope. The heart of an elephant weighs 12–21 kg (26–46 lb). Its apex has two pointed ends, an unusual trait among mammals. In addition,

670-418: A protective crust. Elephants have difficulty releasing heat through the skin because of their low surface-area-to-volume ratio , which is many times smaller than that of a human. They have even been observed lifting up their legs to expose their soles to the air. Elephants only have sweat glands between the toes, but the skin allows water to disperse and evaporate, cooling the animal. In addition, cracks in

737-541: A single species, Loxodonta africana , but molecular studies have affirmed their status as separate species. Mammoths ( Mammuthus ) are nested within living elephants as they are more closely related to Asian elephants than to African elephants. Another extinct genus of elephant, Palaeoloxodon , is also recognised, which appears to have close affinities with African elephants and to have hybridised with African forest elephants. Over 180 extinct members of order Proboscidea have been described. The earliest proboscideans,

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804-526: A specific person led you to this page, you may wish to change that link by adding the person's given name (s) to the link. Retrieved from " https://en.wikipedia.org/w/index.php?title=Gelfand&oldid=1176253339 " Categories : Surnames Germanic-language surnames Russian-language surnames Surnames of Jewish origin Yiddish-language surnames Hidden categories: Articles with short description Short description

871-440: A strong grasp. The flexibility of the trunk is aided by the numerous wrinkles in the skin. The African elephants have two finger-like extensions at the tip of the trunk that allow them to pluck small food. The Asian elephant has only one and relies more on wrapping around a food item. Asian elephant trunks have better motor coordination . The trunk's extreme flexibility allows it to forage and wrestle other elephants with it. It

938-661: A top speed of 25 km/h (16 mph). At this speed, most other quadrupeds are well into a gallop, even accounting for leg length. Spring-like kinetics could explain the difference between the motion of elephants and other animals. The cushion pads expand and contract, and reduce both the pain and noise that would come from a very heavy animal moving. Elephants are capable swimmers: they can swim for up to six hours while completely waterborne, moving at 2.1 km/h (1 mph) and traversing up to 48 km (30 mi) continuously. The brain of an elephant weighs 4.5–5.5 kg (10–12 lb) compared to 1.6 kg (4 lb) for

1005-432: A year. As the tusk develops, it is topped with smooth, cone-shaped enamel that eventually wanes. The dentine is known as ivory and has a cross-section of intersecting lines, known as "engine turning", which create diamond-shaped patterns. Being living tissue, tusks are fairly soft and about as dense as the mineral calcite . The tusk protrudes from a socket in the skull, and most of it is external. At least one-third of

1072-409: Is accessible. They are considered to be keystone species , due to their impact on their environments. Elephants have a fission–fusion society , in which multiple family groups come together to socialise. Females (cows) tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The leader of a female group, usually the oldest cow, is known as

1139-718: Is derived from the Latin word elephas ( genitive elephantis ) ' elephant ' , which is the Latinised form of the ancient Greek ἐλέφας ( elephas ) (genitive ἐλέφαντος ( elephantos )), probably from a non- Indo-European language , likely Phoenician . It is attested in Mycenaean Greek as e-re-pa (genitive e-re-pa-to ) in Linear B syllabic script. As in Mycenaean Greek, Homer used

1206-504: Is different from Wikidata All set index articles Elephant Elephants are the largest living land animals. Three living species are currently recognised: the African bush elephant ( Loxodonta africana ), the African forest elephant ( L. cyclotis ), and the Asian elephant ( Elephas maximus ). They are the only surviving members of the family Elephantidae and

1273-440: Is inwardly concave, thus forming a central tube up which moisture is sucked. Suction takes place due to the contraction and expansion of a sac in the head. A specific example of the proboscis being used for feeding is in the species Deilephila elpenor . In this species, the moth hovers in front of the flower and extends its long proboscis to attain its food. A few Lepidoptera species lack mouth parts and therefore do not feed in

1340-417: Is powerful enough to lift up to 350 kg (770 lb), but it also has the precision to crack a peanut shell without breaking the seed. With its trunk, an elephant can reach items up to 7 m (23 ft) high and dig for water in the mud or sand below. It also uses it to clean itself. Individuals may show lateral preference when grasping with their trunks: some prefer to twist them to the left, others to

1407-600: Is typically more worn down, as it is shorter and blunter. For African elephants, tusks are present in both males and females and are around the same length in both sexes, reaching up to 300 cm (9 ft 10 in), but those of males tend to be more massive. In the Asian species, only the males have large tusks. Female Asians have very small tusks, or none at all. Tuskless males exist and are particularly common among Sri Lankan elephants . Asian males can have tusks as long as Africans', but they are usually slimmer and lighter;

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1474-564: The Bering Strait into the Holocene, with their latest survival being on Wrangel Island , where they persisted until around 4,000 years ago. Over the course of their evolution, probobscideans grew in size. With that came longer limbs and wider feet with a more digitigrade stance, along with a larger head and shorter neck. The trunk evolved and grew longer to provide reach. The number of premolars, incisors, and canines decreased, and

1541-842: The Early Pleistocene , all non-elephantid probobscidean genera outside of the Americas became extinct with the exception of Stegodon , with gomphotheres dispersing into South America as part of the Great American interchange , and mammoths migrating into North America around 1.5 million years ago. At the end of the Early Pleistocene, around 800,000 years ago the elephantid genus Palaeoloxodon dispersed outside of Africa, becoming widely distributed in Eurasia. Proboscideans were represented by around 23 species at

1608-775: The Etosha region of Namibia. Elephants go on seasonal migrations in response to changes in environmental conditions. In northern Botswana, they travel 325 km (202 mi) to the Chobe River after the local waterholes dry up in late August. Proboscis First attested in English in 1609 from Latin proboscis , the latinisation of the Ancient Greek προβοσκίς ( proboskis ), which comes from πρό ( pro ) 'forth, forward, before' + βόσκω ( bosko ), 'to feed, to nourish'. The plural as derived from

1675-756: The International Union for Conservation of Nature (IUCN). One of the biggest threats to elephant populations is the ivory trade , as the animals are poached for their ivory tusks. Other threats to wild elephants include habitat destruction and conflicts with local people. Elephants are used as working animals in Asia. In the past, they were used in war; today, they are often controversially put on display in zoos, or employed for entertainment in circuses . Elephants have an iconic status in human culture and have been widely featured in art, folklore, religion, literature, and popular culture. The word elephant

1742-485: The imago . Others, such as the family Micropterigidae , have mouth parts of the chewing kind. The study of insect mouthparts was helpful for the understanding of the functional mechanism of the proboscis of butterflies (Lepidoptera) to elucidate the evolution of new form-function. The study of the proboscis of butterflies revealed surprising examples of adaptations to different kinds of fluid food, including nectar , plant sap , tree sap, dung and of adaptations to

1809-405: The incisors , known as the tusks ; 12 deciduous premolars ; and 12 molars . Unlike most mammals, teeth are not replaced by new ones emerging from the jaws vertically. Instead, new teeth start at the back of the mouth and push out the old ones. The first chewing tooth on each side of the jaw falls out when the elephant is two to three years old. This is followed by four more tooth replacements at

1876-507: The matriarch . Males (bulls) leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate. They enter a state of increased testosterone and aggression known as musth , which helps them gain dominance over other males as well as reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in

1943-480: The order Proboscidea ; extinct relatives include mammoths and mastodons . Distinctive features of elephants include a long proboscis called a trunk, tusks , large ear flaps, pillar-like legs, and tough but sensitive grey skin. The trunk is prehensile , bringing food and water to the mouth and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining

2010-423: The pleural cavity . This may allow the animal to deal with the pressure differences when its body is underwater and its trunk is breaking the surface for air. Elephants breathe mostly with the trunk but also with the mouth. They have a hindgut fermentation system, and their large and small intestines together reach 35 m (115 ft) in length. Less than half of an elephant's food intake gets digested, despite

2077-487: The temporal gland , located on both sides of the head. This organ is associated with sexual behaviour, and males secrete a fluid from it when in musth . Females have also been observed with these secretions. Elephants are herbivorous and will eat leaves, twigs, fruit, bark, grass, and roots. African elephants mostly browse , while Asian elephants mainly graze . They can eat as much as 300 kg (660 lb) of food and drink 40 L (11 US gal) of water in

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2144-432: The ventricles of the heart split towards the top, a trait also found in sirenians. When upright, the elephant's heart beats around 28 beats per minute and actually speeds up to 35 beats when it lies down. The blood vessels are thick and wide and can hold up under high blood pressure. The lungs are attached to the diaphragm , and breathing relies less on the expanding of the ribcage. Connective tissue exists in place of

2211-596: The "shovel tuskers" like Platybelodon ), choerolophodontids and stegodontids . Around 10 million years ago, the earliest members of the family Elephantidae emerged in Africa, having originated from gomphotheres. Elephantids are distinguished from earlier proboscideans by a major shift in the molar morphology to parallel lophs rather than the cusps of earlier proboscideans, allowing them to become higher-crowned (hypsodont) and more efficient in consuming grass. The Late Miocene saw major climactic changes, which resulted in

2278-528: The African Eritherium and Phosphatherium are known from the late Paleocene . The Eocene included Numidotherium , Moeritherium , and Barytherium from Africa. These animals were relatively small and, some, like Moeritherium and Barytherium were probably amphibious. Later on, genera such as Phiomia and Palaeomastodon arose; the latter likely inhabited more forested areas. Proboscidean diversification changed little during

2345-484: The Greek is proboscides , but in English the plural form proboscises occurs frequently. The most common usage is to refer to the tubular feeding and sucking organ of certain invertebrates such as insects (e.g., moths, butterflies , and mosquitoes), worms (including Acanthocephala , proboscis worms ) and gastropod molluscs . The Acanthocephala , the thorny-headed worms or spiny-headed worms, are characterized by

2412-613: The Greek word to mean ivory , but after the time of Herodotus , it also referred to the animal. The word elephant appears in Middle English as olyfaunt ( c.  1300 ) and was borrowed from Old French oliphant (12th century). Orycteropodidae [REDACTED] Macroscelididae [REDACTED] Chrysochloridae [REDACTED] Tenrecidae [REDACTED] Procaviidae [REDACTED] Elephantidae [REDACTED] Dugongidae [REDACTED] Trichechidae [REDACTED] Elephants belong to

2479-660: The Oligocene. One notable species of this epoch was Eritreum melakeghebrekristosi of the Horn of Africa , which may have been an ancestor to several later species. early proboscideans, e.g. Moeritherium [REDACTED] Deinotheriidae [REDACTED] Mammutidae [REDACTED] Gomphotheriidae [REDACTED] Stegodontidae [REDACTED] Loxodonta [REDACTED] Palaeoloxodon [REDACTED] Mammuthus [REDACTED] Elephas [REDACTED] A major event in proboscidean evolution

2546-480: The ages of four to six, 9–15, 18–28, and finally in their early 40s. The final (usually sixth) set must last the elephant the rest of its life. Elephant teeth have loop-shaped dental ridges, which are more diamond-shaped in African elephants. The tusks of an elephant are modified second incisors in the upper jaw. They replace deciduous milk teeth at 6–12 months of age and keep growing at about 17 cm (7 in)

2613-642: The beginning of the Late Pleistocene . Proboscideans underwent a dramatic decline during the Late Pleistocene as part of the Late Pleistocene extinctions of most large mammals globally, with all remaining non-elephantid proboscideans (including Stegodon , mastodons , and the American gomphotheres Cuvieronius and Notiomastodon ) and Palaeoloxodon becoming extinct, with mammoths only surviving in relict populations on islands around

2680-453: The cheek teeth (molars and premolars) became longer and more specialised. The incisors developed into tusks of different shapes and sizes. Several species of proboscideans became isolated on islands and experienced insular dwarfism , some dramatically reducing in body size, such as the 1 m (3 ft 3 in) tall dwarf elephant species Palaeoloxodon falconeri . Elephants are the largest living terrestrial animals. Some species of

2747-402: The decline and extinction of many proboscidean groups. The earliest members of the modern genera of Elephantidae appeared during the latest Miocene–early Pliocene around 5 million years ago. The elephantid genera Elephas (which includes the living Asian elephant) and Mammuthus (mammoths) migrated out of Africa during the late Pliocene, around 3.6 to 3.2 million years ago. Over the course of

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2814-420: The ear is considerably thinner. Elephants are typically grey, but African elephants look brown or reddish after rolling in coloured mud. Asian elephants have some patches of depigmentation, particularly on the head. Calves have brownish or reddish hair, with the head and back being particularly hairy. As elephants mature, their hair darkens and becomes sparser, but dense concentrations of hair and bristles remain on

2881-525: The elephant uses its trunk as a snorkel . The trunk also acts as a sense organ. Its sense of smell may be four times greater than a bloodhound 's nose. The infraorbital nerve , which makes the trunk sensitive to touch, is thicker than both the optic and auditory nerves. Whiskers grow all along the trunk, and are particularly packed at the tip, where they contribute to its tactile sensitivity. Unlike those of many mammals, such as cats and rats, elephant whiskers do not move independently ("whisk") to sense

2948-409: The environment, and in some cases, capturing prey or attaching to hosts. Three major types of proboscises have been identified: pleurembolic (partially retractable), acrembolic (fully retractable), and intraembolic (variable in structure). Acrembolic proboscises are usually found in parasitic gastropods. The elephant's trunk and the tapir 's elongated nose are called "proboscis", as is the snout of

3015-402: The environment; the trunk itself must move to bring the whiskers into contact with nearby objects. Whiskers grow in rows along each side on the ventral surface of the trunk, which is thought to be essential in helping elephants balance objects there, whereas they are more evenly arranged on the dorsal surface. The number and patterns of whiskers are distinctly different between species. Damaging

3082-410: The extinct elephant genus Palaeoloxodon considerably exceeded modern elephants in size making them among the largest land mammals ever. The skeleton is made up of 326–351 bones. The vertebrae are connected by tight joints, which limit the backbone's flexibility. African elephants have 21 pairs of ribs, while Asian elephants have 19 or 20 pairs. The skull contains air cavities ( sinuses ) that reduce

3149-585: The family Elephantidae , the sole remaining family within the order Proboscidea . Their closest extant relatives are the sirenians ( dugongs and manatees ) and the hyraxes , with which they share the clade Paenungulata within the superorder Afrotheria . Elephants and sirenians are further grouped in the clade Tethytheria . Three species of living elephants are recognised; the African bush elephant ( Loxodonta africana ), forest elephant ( Loxodonta cyclotis ), and Asian elephant ( Elephas maximus ). African elephants were traditionally considered

3216-519: The front and hind limbs can support an elephant's weight, although 60% is borne by the front. The position of the limbs and leg bones allows an elephant to stand still for extended periods of time without tiring. Elephants are incapable of turning their manus as the ulna and radius of the front legs are secured in pronation . Elephants may also lack the pronator quadratus and pronator teres muscles or have very small ones. The circular feet of an elephant have soft tissues, or "cushion pads" beneath

3283-542: The largest ear flaps. The ossicles are adapted for hearing low frequencies, being most sensitive at 1 kHz . Lacking a lacrimal apparatus (tear duct), the eye relies on the harderian gland in the orbit to keep it moist. A durable nictitating membrane shields the globe. The animal's field of vision is compromised by the location and limited mobility of the eyes. Elephants are dichromats and they can see well in dim light but not in bright light. The elongated and prehensile trunk, or proboscis , consists of both

3350-402: The largest recorded was 302 cm (9 ft 11 in) long and weighed 39 kg (86 lb). Hunting for elephant ivory in Africa and Asia has resulted in an effective selection pressure for shorter tusks and tusklessness. An elephant's skin is generally very tough, at 2.5 cm (1 in) thick on the back and parts of the head. The skin around the mouth, anus , and inside of

3417-449: The manus or pes , which allow them to bear the animal's great mass. They appear to have a sesamoid , an extra "toe" similar in placement to a giant panda 's extra "thumb", that also helps in weight distribution. As many as five toenails can be found on both the front and hind feet. Elephants can move both forward and backward, but are incapable of trotting , jumping , or galloping . They can move on land only by walking or ambling :

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3484-425: The middle with a thinner tip and supported by a thicker base. They contain numerous blood vessels called capillaries . Warm blood flows into the capillaries, releasing excess heat into the environment. This effect is increased by flapping the ears back and forth. Larger ear surfaces contain more capillaries, and more heat can be released. Of all the elephants, African bush elephants live in the hottest climates and have

3551-413: The nose and upper lip, which fuse in early fetal development. This versatile appendage contains up to 150,000 separate muscle fascicles , with no bone and little fat. These paired muscles consist of two major types: superficial (surface) and internal. The former are divided into dorsal, ventral , and lateral muscles, while the latter are divided into transverse and radiating muscles. The muscles of

3618-417: The presence of an eversible proboscis, armed with spines, which they use to pierce and hold the gut wall of their host. The mouth parts of Lepidoptera ( butterflies and moths ) mainly consist of the sucking kind; this part is known as the proboscis or 'haustellum'. The proboscis consists of two tubes held together by hooks and separable for cleaning. The proboscis contains muscles for operating. Each tube

3685-423: The process lasting a day. An elephant's bladder can store up to 18 litres of urine and its kidneys can produce more than 50 litres of urine per day. A male elephant's testes, like other Afrotheria , are internally located near the kidneys. The penis can be as long as 100 cm (39 in) with a 16 cm (6 in) wide base. It curves to an 'S' when fully erect and has an orifice shaped like

3752-493: The right. Elephant trunks are capable of powerful siphoning. They can expand their nostrils by 30%, leading to a 64% greater nasal volume, and can breathe in almost 30 times faster than a human sneeze, at over 150 m/s (490 ft/s). They suck up water, which is squirted into the mouth or over the body. The trunk of an adult Asian elephant is capable of retaining 8.5 L (2.2 US gal) of water. They will also sprinkle dust or grass on themselves. When underwater,

3819-401: The skin may reduce dehydration and allow for increased thermal regulation in the long term. To support the animal's weight, an elephant's limbs are positioned more vertically under the body than in most other mammals. The long bones of the limbs have cancellous bones in place of medullary cavities . This strengthens the bones while still allowing haematopoiesis (blood cell creation). Both

3886-456: The skull, which serve as protection. Because of the size of the head, the neck is relatively short to provide better support. Elephants are homeotherms and maintain their average body temperature at ~ 36 °C (97 °F), with a minimum of 35.2 °C (95.4 °F) during the cool season, and a maximum of 38.0 °C (100.4 °F) during the hot dry season. Elephant ear flaps, or pinnae , are 1–2 mm (0.039–0.079 in) thick in

3953-472: The tip of the tail and parts of the head and genitals. Normally, the skin of an Asian elephant is covered with more hair than its African counterpart. Their hair is thought to help them lose heat in their hot environments. Although tough, an elephant's skin is very sensitive and requires mud baths to maintain moisture and protection from burning and insect bites. After bathing, the elephant will usually use its trunk to blow dust onto its body, which dries into

4020-514: The trunk connect to a bony opening in the skull. The nasal septum consists of small elastic muscles between the nostrils, which are divided by cartilage at the base. A unique proboscis nerve – a combination of the maxillary and facial nerves – lines each side of the appendage. As a muscular hydrostat , the trunk moves through finely controlled muscle contractions, working both with and against each other. Using three basic movements: bending, twisting, and longitudinal stretching or retracting,

4087-422: The trunk has near unlimited flexibility. Objects grasped by the end of the trunk can be moved to the mouth by curving the appendage inward. The trunk can also bend at different points by creating stiffened "pseudo-joints". The tip can be moved in a way similar to the human hand. The skin is more elastic on the dorsal side of the elephant trunk than underneath; allowing the animal to stretch and coil while maintaining

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4154-508: The trunk would be detrimental to an elephant's survival, although in rare cases, individuals have survived with shortened ones. One trunkless elephant has been observed to graze using its lips with its hind legs in the air and balancing on its front knees. Floppy trunk syndrome is a condition of trunk paralysis recorded in African bush elephants and involves the degeneration of the peripheral nerves and muscles. The disorder has been linked to lead poisoning. Elephants usually have 26 teeth:

4221-433: The tusk contains the pulp , and some have nerves that stretch even further. Thus, it would be difficult to remove it without harming the animal. When removed, ivory will dry up and crack if not kept cool and wet. Tusks function in digging, debarking, marking, moving objects, and fighting. Elephants are usually right- or left-tusked, similar to humans, who are typically right- or left-handed . The dominant, or "master" tusk,

4288-456: The use of pollen as complementary food in Heliconius butterflies. An extremely long proboscis appears within different groups of flower-visiting insects, but is relatively rare. Some evolutionary lineages of gastropods have evolved a proboscis. In gastropods, the proboscis is an elongation of the snout with the ability to retract inside the body; it can be used for feeding, sensing

4355-419: The weight of the skull while maintaining overall strength. These cavities give the inside of the skull a honeycomb -like appearance. By contrast, the lower jaw is dense. The cranium is particularly large and provides enough room for the attachment of muscles to support the entire head. The skull is built to withstand great stress, particularly when fighting or using the tusks. The brain is surrounded by arches in

4422-463: The wild. They communicate by touch, sight, smell, and sound; elephants use infrasound and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans . They appear to have self-awareness , and possibly show concern for dying and dead individuals of their kind. African bush elephants and Asian elephants are listed as endangered and African forest elephants as critically endangered by

4489-670: Was the collision of Afro-Arabia with Eurasia, during the Early Miocene, around 18–19 million years ago, allowing proboscideans to disperse from their African homeland across Eurasia and later, around 16–15 million years ago into North America across the Bering Land Bridge . Proboscidean groups prominent during the Miocene include the deinotheres , along with the more advanced elephantimorphs , including mammutids (mastodons), gomphotheres , amebelodontids (which includes

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