Have you seen a dolphin before? Not many people have. But you may have seen it on the internet and TVs, and you might be wondering, how they really look like in real life? Let’s look at the typical dolphin appearance.
Dolphins range in size from the relatively small 1.7-metre-long (5 ft 7 in) long and 50-kilogram (110-pound) bodied Maui’s dolphin to the 9.5 m (31 ft 2 in) and 10-tonne (11-short-ton) killer whale. Dolphins can sometimes leap about 30 feet (9.1 m). Several species of dolphins exhibit sexual dimorphism, in that the males are larger than females. They have streamlined bodies and two limbs that are modified into flippers. Though not quite as flexible as seals, some dolphins can travel at speeds 29 kilometres (18 mi) per hour for short distances. Dolphins use their conical shaped teeth to capture fast-moving prey. They have well-developed hearing which is adapted for both air and water and is so well developed that some can survive even if they are blind. Some species are well adapted for diving to great depths. They have a layer of fat, or blubber, under the skin to keep warm in the cold water. (Wikipedia)
Have you ever wondered, why these animals are blessed with a permanent smile? Question for another day though.
Where Dolphins are Found
Although dolphins are widespread, most species of them prefer the warmer waters of the tropic zones, but some, like the right whale dolphin, prefer colder climates. Dolphins feed largely on fish and squid, but a few, like the killer whale, feed on large mammals, like seals. Male dolphins typically mate with multiple females every year, but females only mate every two to three years. Calves are typically born in the spring and summer months and females bear all the responsibility for raising them. Mothers of some species fast and nurse their young for a relatively long period of time. Dolphins produce a variety of vocalizations, usually in the form of clicks and whistles.
Dolphins are sometimes hunted in places such as Japan, in an activity known as dolphin drive hunting. Besides drive hunting, they also face threats from bycatch, habitat loss, and marine pollution. Dolphins have been depicted in various cultures worldwide. Dolphins occasionally feature in literature and film, as in the film series Free Willy. Dolphins are sometimes kept in captivity and trained to perform tricks. The most common dolphin species in captivity is the bottlenose dolphin, while there are around 60 killer whales in captivity. (wikipedia)
What can dolphins do?
Dolphins are one of the most (if not the most) intelligent animals on earth, and as such are very social and capable of exhibiting a very high level of organization and culture. Among the things dolphins can do, we want to mention a few:
A. Dolphins can learn:
Dolphins are known to teach, learn, cooperate, scheme, and grieve. The neocortex of many species is home to elongated spindle neurons that, prior to 2007, were known only in hominids. In humans, these cells are involved in social conduct, emotions, judgment, and theory of mind. Cetacean spindle neurons are found in areas of the brain that are homologous to where they are found in humans, suggesting that they perform a similar function. (wikipedia)
If you have been to aquariums you will see dolphins in exhibition, performing different stunts like:
Video of dolphins performing sports
Video of dolphin doing amazing ball returns
Amazing high jumps:
Dolphins frequently leap above the water surface, this being done for various reasons. When travelling, jumping can save the dolphin energy as there is less friction while in the air. This type of travel is known as porpoising. Other reasons include orientation, social displays, fighting, non-verbal communication, entertainment and attempting to dislodge parasites (wikipedia)
Video of Dolphin Jumps
B. Dynamic Echolocation System
Echolocation, also called bio sonar, is a biological sonar used by several animal species. Echolocating animals emit calls out to the environment and listen to the echoes of those calls that return from various objects near them. They use these echoes to locate and identify the objects. Echolocation is used for navigation, foraging, and hunting in various environments.
In dolphins, and other marine mammals, there is no great difference between the outer and inner environments. Instead of sound passing through the outer ear to the middle ear, dolphins receive sound through the throat, from which it passes through a low-impedance fat-filled cavity to the inner ear. The dolphin ear is acoustically isolated from the skull by air-filled sinus pockets, which allow for greater directional hearing underwater. Dolphins send out high frequency clicks from an organ known as a melon. This melon consists of fat, and the skull of any such creature containing a melon will have a large depression. This allows dolphins to produce biosonar for orientation. Though most dolphins do not have hair, they do have hair follicles that may perform some sensory function. Beyond locating an object, echolocation also provides the animal with an idea on an object’s shape and size, though how exactly this works is not yet understood. The small hairs on the rostrum of the boto are believed to function as a tactile sense, possibly to compensate for the boto’s poor eyesight. (wikipedia)
Echolocation In Dolphins Explained (Video)
C. Dolphins can Socialize
Dolphins are highly social animals, often living in pods of up to a dozen individuals, though pod sizes and structures vary greatly between species and locations. In places with a high abundance of food, pods can merge temporarily, forming a superpod; such groupings may exceed 1,000 dolphins. Membership in pods is not rigid; interchange is common. They establish strong social bonds, and will stay with injured or ill members, helping them to breathe by bringing them to the surface if needed.
This altruism does not appear to be limited to their own species. The dolphin Moko in New Zealand has been observed guiding a female pygmy sperm whale together with her calf out of shallow water where they had stranded several times. They have also been seen protecting swimmers from sharks by swimming circles around the swimmers or charging the sharks to make them go away.
Dolphins communicate using a variety of clicks, whistle-like sounds and other vocalizations. Dolphins also use nonverbal communication by means of touch and posturing.
Dolphins also display culture, something long believed to be unique to humans (and possibly other primate species). In May 2005, a discovery in Australia found Indo-Pacific bottlenose dolphins (Tursiops aduncus) teaching their young to use tools. They cover their snouts with sponges to protect them while foraging. This knowledge is mostly transferred by mothers to daughters, unlike simian primates, where knowledge is generally passed on to both sexes. Using sponges as mouth protection is a learned behavior. Another learned behavior was discovered among river dolphins in Brazil, where some male dolphins use weeds and sticks as part of a sexual display.
Forms of care-giving between fellows and even for members of different species are recorded in various species – such as trying to save weakened fellows or female pilot whales holding up dead calves for long periods.
Dolphins engage in acts of aggression towards each other. The older a male dolphin is, the more likely his body is to be covered with bite scars. Male dolphins can get into disputes over companions and females. Acts of aggression can become so intense that targeted dolphins sometimes go into exile after losing a fight.
Male bottlenose dolphins have been known to engage in infanticide. Dolphins have also been known to kill porpoises for reasons which are not fully understood, as porpoises generally do not share the same diet as dolphins and are therefore not competitors for food supplies. The Cornwall Wildlife Trust records about one such death a year. Possible explanations include misdirected infanticide, misdirected sexual aggression or play behaviour
Dolphin facts for kids
A poem for dolphins
Dolphins are so cute
But if we pollute
Their natural home
In the aquatic biome
We put them in danger
Their lives matter
They have empathy for humans
But we have to remember that dolphins
Are wild animals
They are highly intelligent marine mammals
With innate needs
They are born knowing they are predators
One of the ocean’s strongest fighters
Dolphins focus on different foods
And help keep the ecosystem balanced
The threats they face need to be managed
To avoid their extinction
We don’t have another option