Elephants
The elephant, not only the largest but the most intelligent of animals, provides us with an excellent example. It is faithful and tenderly loving to the female of its choice, mating only every 3rd year and then for no more than 5 days, and so secretly as never to be seen, until, on the 6th day, it appears and goes at once to wash its whole body in the river, unwilling to return to the herd until thus purified. Such good and modest habits are an example to husband and wife. ~ French Catholic priest Francis de Sales
Elephants are the largest living land animal. African bull elephants can be up to 4 meters high and weigh 10,000 kg or more.
Size is an adaptive challenge. Weight goes up by the cube, while the cross-section of a bone is related to size by the square.
Large animals therefore must evolve to keep their legs straight under their bodies, such that the weight is taken down the length of the bones and not across them. In full-grown elephants, the femur is slightly twisted to achieve this, with the consequence that elephants walk with straight legs, and they cannot gallop.
The elephant lineage began 58 MYA in Africa, with mammals the size of current-day pigs. From there they spread into Asia, eventually colonizing every continent except Australia and Antarctica.
Elephants now live in the savannas, forests, and deserts of Africa, as well as in some Asian forests. 3 elephant species still exist: the African savanna (bush) elephant, the African forest elephant, and the Asian elephant, also known as the Indian elephant.
Other elephant species, such as the woolly mammoth, were hunted by men to extinction. The woolly mammoth was more closely related to the Asian elephant than the Africans.
Elephants are fond of water and are good swimmers. They colonized a number of islands. In doing so, they invariably shrank, as is common for island creatures with mainland ancestors. One reason is the limited supply of food. The other is the loss of large predators, thereby relaxing the selective pressure for size.
Pygmy elephants did not have the twisted femur that is characteristic of large elephants. It may be supposed that they were friskier animals. But that is uncertain, as all are extinct, probably from the predation of men.
The elephant’s only living relatives are manatees, dugongs, and hyraxes. None bear much resemblance to elephants. Manatees and dugongs are aquatic cows.
Sociality
Elephants are highly gregarious. At every age, they like to fondle and caress one another.
Newborns nurse until 2 years old. During that time, stroking and cuddling between mother and child is nonstop.
Upbringing is a community affair. Females look after others’ children (alloparenting).
Female elephants living in herds of 20 to 100, led by an older matriarch. The quality of leadership matters.
Typical elephant life span is 50 to 70 years. Matriarchs 60 years or older – tough survivors – are better at assessing threats, and having the group respond appropriately. Owing to experience, elder elephants are better leaders.
A seasoned veteran elephant can easily distinguish between a male or female lion roar. Males pose a greater threat. A group with an older matriarch organizes more quickly, and moves more assuredly as a united front, marching to challenge a supposed predator.
Elephants are migratory. Herd leaders choose routes from memory, considering the terrain, changes of seasons, rain patterns, and the best water holes along the way.
Experienced elephant leaders know when to lead and when to let events naturally flow. A senior leader may not be at the front of the group in the morning walk to the waterhole, but others pay attention to her for cues: where she goes, and how she reacts.
Females stay with their natal group for life, developing strong social bonds. The social structure of elephant groups is dynamic. But one thing is certain. Behaviors that show disrespect to the leadership are punished via ostracism. There is a hierarchy of social power in elephant society. Elephant social rank is commonly hereditary: a daughter inheriting her mother’s social position.
When a young male reaches sexual maturity, he is told to go find his way. He roams until he can ally himself with other bachelor bulls his own age.
The mating season is short; only a few days a year. The funk of a cow attracts bulls, but she might also call out for a hot time.
Females prefer, larger, stronger, and older males. Such selection tends to improve an offspring’s survival chances.
As females are generally faster than males, a cow can run from an unwelcome approach. Courtship involves affectionate foreplay by both, including nuzzling, trunk intertwining, and elephant French kissing: putting their trunks in each other’s mouths.
Mating is a short fling, but cows and bulls both commonly engage in same-sex bonding and mounting. Almost half of all elephant sexual encounters are homosexual.
Older males are generally solitary: foraging and traveling alone for much of the time. Besides mating, older males are welcomed by females on their occasional social visits.
Senses
Elephants are extremely tactile. Besides touch, their olfactory and auditory senses are most significant.
Elephants produce low frequency sounds: from 5–9,000 Hz. Low frequencies are the best long-distance travelers. Hence, elephants can communicate many kilometers apart.
Elephants have a keen sense of smell. Their nasal cavity has 7 turbinates, compared to 5 in dogs, and 4 in humans. Elephants’ sense of smell is 5 times more acute than people, twice that of dogs, and even better than rats. If they smell something unseen amid leaf litter, they use their trunks as leaf blowers to reveal what is underneath.
Elephants are dichromats, enabling them to detect the quality of plant parts. Their eyesight is thought to be good in dull light, but considerably reduced in bright light.
Diet
Although sauropod dinosaurs somehow managed to get enough to eat with small heads, endotherms that feed in bulk on small food items need to have mouths somewhat in proportion to their bodies. Thus, large mammals – hippos, baleen whales, and elephants – have sizable mouths.
One way of taking in an ample mouthful is to sweep food up and stuff it in. This is basically how an elephant feeds: using its trunk.
An elephant’s huge metabolism requires it be constantly eating. This owes in large part to the fact that elephants are hind-gut fermenters, which means that they do not get as much goodness out of their food as other mammals that chew their cud.
An adult elephant consumes 45 tonnes of vegetation annually, in a wide variety. It may spend 15 to 19 hours a day feeding.
Despite the need for volume, elephants are picky eaters: selectively choosing plants species and specific parts. Elephants know which plants make for a healthy diet and which to avoid because of their secondary metabolites.
While an elephant attack is a temporary setback to the victimized plant, it often has a longer-term beneficial effect. Such pruning inspires the plant to thicken as it fills in again.
The voluminous consumption patterns of elephants can take so much of a toll on their favored vegetation that it can affect the composition of plants in the immediate area, as ignored plants gain an advantage. That disadvantage to elephant-chosen plants has a compensating offset in elephant digestion.
An elephant’s digestive system, although overworked, is not especially efficient. An elephant digests 44% of its hay intake compared to 50–70% for a cow. Unlike cattle, elephants cannot digest cellulose. A lot of weeds and seeds pass through an elephant unscathed.
Thus, elephants propagate the plants they enjoy the most. This expands those plants’ ranges. In Africa, at least 30 tree species rely upon elephants for seed dispersal.
So, despite massive appetites and all the wear on the vegetation, elephants are a keystone species, especially for plants. They are also instrumental to other animals, in at least clearing good travel routes.
To acquire a healthy microbe supply, infants eat their mothers’ dung. Whether this is innate or taught is not known.
The Trunk
The elephant’s trunk is one of the most eccentric organs in the animal kingdom, and certainly the most versatile. It is a radical elongation of the nose and upper lip, which in an adult may reach 2 meters. 2 nostrils run a trunk’s full length, so that food edibility may be checked by scent. Elephants breathe through their trunks.
When swimming, the trunk is a terrific snorkel. Of all land animals, elephants are the most powerful swimmer; not what one might expect of such a massive animal with mobility limitations on land. Their legs bend well for swimming, and their feet pads splay out to paddle.
An elephant drinks by filling its trunk with water, and then pours the water into its mouth. A trunk can hold up to 14 liters of water.
Breathing water through the trunk incites the same cough reflex that humans encounter when breathing water.
An African elephant’s trunk has 2 opposing tips, analogous to the human thumb and forefinger. Asian elephants make do with a single tip.
One of the first things a newborn must learn is how to use its trunk. Infants nurse through their mouth. The rubbery, 30 cm dangling object is in the way. An infant flops its trunk back onto its forehead to suckle.
It takes 6 to 8 months for a baby elephant to learn to control its trunk. The problem is like a human infant learning to use its hands. The difference is that an elephant’s trunk has at least 150,000 muscle fascicles (bundles) in 6 major muscle groups, whereas the human hand has 34 muscles that move the fingers and thumb: 17 in the palm and 18 in the forearm.
The primary function of the prehensile trunk is to harvest food. For 16 to 18 hours each day, elephants are on the move, feeding and foraging.
With foraging eating up their schedules, elephants sleep only 3 to 6 hours a day. How elephants and other large herbivores get by on so little sleep is not understood.
The trunk also acts as an olfactory organ. The trunk can function as an olfactory periscope, letting elephants smell one another from kilometers away: an astonishing sensitivity.
An elephant easily picks up and carries things in its trunk. A mother will pick up and whisk her infant away in an emergency. Elephants break off tree branches or pick them up to wave away pesky biting flies.
An adult elephant’s trunk is strong enough to lift 200–270 kg, and precise enough to pluck a single blade of grass. Its trunk is an elephant’s most sensitive body part.
To see off an unwanted approach, an elephant will kick dirt at the intruder, or flail at it with its trunk if it comes too close. But the trunk is to be protected. An angry elephant about to charge first curls its trunk in toward its body. An elephant cannot survive its trunk being damaged.
The trunk plays a major role in social interactions. Elephant friends greet each other by entwining trunks. Trunks caress during courtship, and in mother-child fondling. Children play-wrestle with their trunks.
A raised trunk can be a warning or threat. A lowered trunk may be a signal of submission.
Teeth
An elephant’s dentition and teeth are like no other animal. All elephants have 26 teeth: 2 upper incisors (tusks), 12 premolars, and 12 molars.
Elephant teeth work by forward-backward grinding, reducing plant matter to pulp. Other animals chew side to side. Ridges of their teeth run the long way. Elephant tooth ridges instead run the width of the tooth.
In most animals, teeth grow from the top and bottom of the mouth. In elephants, teeth grow from the back and push forward. The only other animal with such migrating teeth is the manatee (an evolutionary relative).
As an elephant’s 1st set of molars grind along, a 2nd set of 4 slightly larger molars grow in behind the 1st. Before the 1st set have been ground to a nub, ready to fall out, the next set are in position.
By the age of 40–50, an elephant has its 6th and last set of teeth. Gradually these last teeth grind away their ridges, becoming smooth. This forces an elephant to leave the herd and seek softer vegetation that grows along the edges of rivers and swamps.
Tusks
Tusks are an elephant’s upper incisors. Tusks are found mostly on Asian males, and on African elephants of both sexes.
Tusks grow continuously. An adult male’s tusk may grow 18 cm each year.
Some elephants have overgrown incisors far shorter than tusks, comprising softer ivory; sometimes referred to as tushes. Tuskless males occasionally occur in Asian and African elephants.
Tusks are used to dig, typically for water or roots. Tusks debark trees, to harvest bark to eat. Tusks dig into baobab trees to get at the tasty pulp within. Tusks help move trees and branches when clearing a path. If necessary, a tusk may be used as a weapon.
Like the handedness of humans, elephants typically prefer a specific tusk. The master tusk is somewhat shorter, and its tip more rounded from wear.
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Elephants care for their skin: spraying it with water as a shower or packing mud on it as a sunscreen. Besides being essential for hygiene and skin care, bathing is pleasurable. While an elephant’s skin is thick and tough, it is also sensitive.
Wet dust or mud packs trap parasites and biting insects. Elephants rub the mud pack against a hard surface, removing most parasites.
Elephants use their ears as fans in the hot Sun. Elephants waggle their ears to communicate.
Communication
Besides various gestures, elephants have a wide range of audible communication techniques: screams, trumpeting, and low frequency oral rumbles that are heard by other elephants through their trunks and feet, as well as ears.
Despite elephants’ ability to speak in tones lower than humans can hear (14–30 hertz), elephant vocalizations are produced in the same way as humans: by vibrating vocal cords.
Rumbles can be heard for many kilometers: up to 50 km for savanna elephants. A rumble goes through both the air and the ground, extending the range. Elephant identify themselves by a rumble name.
Elephants are not the only species to use infrasound. Squid, whales, alligators, lions, rhinoceros, giraffes, and some birds also use low frequency communication. Some hear through the air or water (for whales), while others detect a communication rumble seismically.
Watering holes are refreshing and a welcome respite. Getting a group to leave takes persuasion. The matriarch of the family lets out a “let’s go” rumble, from which a conversation among the group ensues.
The departure conversation coordinates the exodus and tells other family groups not to approach the watering hole until they are gone, to avoid unwelcome mass chaos.
Elephants can mimic sounds and learn new vocabulary. An African elephant spent 18 years at a Swiss zoo with 2 Asian elephants. The African learned to make the chirpy sounds native to the language of his Asian companions but not used among African elephants.
Koshik
Koshik was a juvenile elephant imprisoned in solitary confinement in a South Korean zoo during his developmental years. The only social contact Koshik had was his keepers. So, to engender social affiliation, Koshik learned to speak the 5 words of Korean which he repeatedly heard: “hello”, “no”, “good”, “sit down”, and “lie down.” Koshik managed to adeptly imitate the human voice by sticking his trunk in his mouth while talking.
An elephant’s large larynx is adapted to produce low-pitched sounds. Koshik figured out how to modify his voice to match the pitch and timbre he heard.
Stockholm syndrome is a psychological phenomenon where hostages emotionally accept their captors and implicitly condone their own capture. One-quarter of kidnap victims show Stockholm syndrome.
Psychology
Despite their majestic and for some strange reason docile and kindly appearance, elephants are really very dangerous creatures. They know their strength, but they don’t use it aggressively, and they abhor fighting or physical violence of any kind. Most of them show noticeable signs of revulsion to bloodshed or death in any form and display distress in face of these things.
Elephants are exceedingly intelligent. They have a form of intelligence which manifests itself in many ways very much like our own. ~ Scottish biologist Ivan Sanderson
Elephants express joy, grief, can create music and art, and display altruism and compassion. They help each other, such as pulling out youngsters mired in mud, and assisting injured members of the herd. Elephants console those in distress.
Elephants understand the value of teamwork. Researchers concocted an experiment that required teamwork to achieve a reward. The elephants quickly grasped the necessity of cooperation: waiting for help, and not even trying if help was not forthcoming.
Elephants grieve and mourn their dead. They often kick or dump dirt on a corpse, or drape branches, leaves, or grass on the dead. Elephants have been seen giving such burying gestures to other animals as well. Elephants visit the graves of their departed loved ones, touching and exploring the bones in sadness.
Captured elephants tied up may lie motionless, consumed with grief, or sink to the ground and cry, tears running down their cheeks.
Elephants are naturally inquisitive and exploratory. They understand gestures, such as pointing, without any training.
One captive elephant with musical inclinations was given a harmonica. Captivated, she enjoyed playing it immensely.
It’s not usually a long ditty, but it always ends in this really big sort of fanfare at the end. ~ American elephant keeper Debbie Flinkman
Elephants have learned that humans may be a threat to them. They can discriminate between children and grown-ups, between men and women, and between speakers of different languages.
Elephants recognize men from a tribe that hunt elephants from children or women, and from men of another tribe which speak a different language and do no hunt elephants. Men who speak the language of known hunters are considered an especial threat. Elephants have specific alarm calls to identify the specific perceived threat, and how imminent it is.
Elephants employ tools as needed. Personal grooming appliances are popular, for scratching and removing ticks. One elephant was observed throwing mud at a rhino over access to a watering hole.
If water is scarce, an elephant may dig a narrow hole in search of a thirst-quenching drink. They somehow know where to dig. Upon finding water and drinking to satisfaction, an elephant may cover the hole to preclude other animals from it.
Elephants learn from one another. Elders are especially diligent to hand down their knowledge to their successors. Elephants teach their young tool use and beauty tips.
Humans tend to suffer a cognitive decline with age, but that has not been apparent to researchers observing elephants.
In the Mirror
Elephants recognize themselves in a mirror. Elephants learn to use a mirror in the same way that people do: in a 4-step process. 1st, initial responses are as if to another elephant. Then, inspect the mirror, including looking behind it, as perhaps the mirror is some sort of glass. Stage 3 is experimentation in front of the mirror, with poses and gestures, to verify how the mirror reflects images. Finally, the concept of mirroring comprehended, check out those body parts that can’t otherwise be seen.
Once understood, an elephant knows how to make use of a mirror if the opportunity arises. Researchers blocked the view of a tasty fruit, hiding it on a shelf behind a wall. An angled mirror above the wall showed the fruit on the shelf. A mirror-savvy elephant looks at the situation and plucks the fruit off the shelf using the mirror as a guide. (It took different sets of researchers decades, from 1983 to 2008, to devise an experiment that satisfied them that elephants possessed mirror self-recognition.)
