Dolphins: Communicators of the Sea

Dolphins are common creatures at rivers and seas. The majority of small toothed whales are dolphins. Dolphins are large sea animals making it part of the suborder Odontoceti, family Delphinidae. Whales and porpoises generally belong to the Cetaceans belonging to family Plantanistidae and Delphinidae, respectively. Often, people used dolphins and porpoises interchangeably denoting same species but porpoises in particular and dolphins are different species. Porpoises belong to family Phocaenidae; it has a rounded snout and chisel-liked teeth.

While dolphins are under family Plantanistidae and Delphinidae, instead of a rounded snout, dolphins have beak like snout and sharp, conical teeth. Dolphins are outgoing creatures; often they are mingling in a group with two to fifteen animal members or more. Most of their communities are dominated by females, its offspring, sisters and other females. Sub adult male dolphins will leave these female-dominated communities to start a group of “bachelor” dolphins; if these dolphins become sexually mature, they can move in the female groups for copulation. These mammals are very playful.

They are often spotted riding the bow wave or stern wake of boats and “surfing” on waves. Chasing and tossing things to one another is one of their favorite plays. If seen jumping or breaching, it indicates enthusiasm for these creatures. Play is important for dolphins for learning and as well as to practice their skills necessary for their life’s survival (Geocities. com, 2006). The current paper focuses on these creatures’ characteristics, particularly their capability to engage in echolocation. Scope The paper begins with an introduction about the dolphin, and their general characteristics as sea creatures.

This is followed by a discussion of their general physiology, including their skin, fin, swimming speed, breathing, and body temperature. The dolphin family is then discussed, with its 33 species – with 5 river species and 6 porpoise species. Of these, the most popular is said to be the bottlenose dolphin which are found in theme parks and are featured in television programs. The next focus would be on the dolphin’s brainpower, specifically in their capacity to make tunes among themselves with a wide range of sounds. Their distinctive communication patterns are likewise expounded on.

The paper concludes with a call for concern and protection from humans, who are supposed to be stewards of these creatures. Overview With regards to its general physiology, dolphins have rubbery skin. They are classified as mammals and have the capacity of maintaining high body temperature. They can hold their breath for several minutes making it easy for them to have rapid and deep dives of more then 300 m (1,000 ft). To date, there are more than 33 different species of dolphins, over 5 different species of river dolphins and more than 6 different species of porpoises.

Though there are many species of dolphins, the most popular are bottlenose dolphins which are frequently featured in television and theme parks. Perhaps their greatest strength is their ability to communicate with one another or to echolocate. This is the counterpart of language among humans. Dolphins create whistles and sounds signifying an action for which another dolphin can understand, it can signal danger for their kind hence they should be alert or a prey is near at hand thus, everybody must prepare; depending on the whistle produced.

They can make signature whistles that carry distinct information. Considering the cognitive abilities of bottlenose dolphins, their vocal learning and copying skills, and their fission–fusion social structure, their communication process can be further studied to provide evidences about their “dolphin messages and echoes. ” Humans have the responsibility of taking care of these creatures, acting as their stewards to prevent them from extinction. General Physiology of a Dolphin A dolphin’s body is smooth having a rubbery-feel of its hairless skin when touched.

The skeletal remnants of five digits in the front appendage form the flippers mainly acting as its balancer during its swim. The rear appendages are almost absent because the small pelvic bones are deep-rooted in the connective tissue at the base of the tail (Dolphin Lovers. com, 2006). The subcutaneous dermal tissue of the dolphin forms its immovable dorsal fin; its tail fin is also dermal in its origin. Its movement is similar with the whales wherein the major force comes from its vertical oscillations of the tail and flukes making it capable to swim at a speed of 37-40 km/h, and in some events, its swimming speed reaches up to 48 km/h.

Dolphins seem restless in traveling the rivers but in reality, it rides the bow wave by making use of the ship’s trust (Stoops, 1996) Dolphins are mammals, hence breathing and maintaining high body temperature is vital. Dolphins maintain its internal temperature at 36. 5 deg to 37. 2 deg C (97. 9 deg to 99 deg F), with its thick layer of dense fat (blubber) under the skin. At the top of its head, a single nostril or blowhole is placed where it acts as its lungs. Dolphins breathe air at the surface every two minutes consisting of brief unpredictable exhalation followed by a longer inhalation.

Dolphins are capable to hold their breath for several minutes making it easy for them to have rapid and deep dives of more then 300 m (1,000 ft) (Dolphin Lovers. com, 2006). Dolphin’s Brainpower Greco and Gini (2005) say that dolphins are capable of making tunes among themselves with a wide range of sounds. Dolphins show evidence that their intelligence is greater than that of dogs. Dolphins learn easily and execute complicated tasks, continuous communications with one another, and their ability to mimic the sounds of human language if they are given ample time to be trained.

Toothed whales have exceptionally large brains including the famously bright dolphins that have capabilities previously only attributed to humans and apes. Cetaceans (dolphins, whales and porpoises) and its ancestors acquired changes specifically in their brain through evolution. One of the reliable evidence to support this claim is by measuring the level of encephalization of a species or a taxonomic group. EQ is the measure of observed brain size relative to expected brain size derived from a regression of brain weight on body weight for a sample of species.

EQ measures how much larger or smaller a species’ total brain size is from what is expected based on brain-body algometry (Greco et. al, 2003). Dolphins and humans share many common attributes. Both creatures are mammals wherein the young are born alive and not hatched from eggs. Air is important for both organisms since it sustains their breathing; the only difference is that dolphins must come up to the surface to breathe in its blowhole on the top of its head and when it dives, the blowhole closes unlike humans that continuously breathe air in its respiratory system.

Wang (1995) asserts that aside from being mammals, communication is one the major attributes keeping these two organisms at par with one another. Humans are capable of language and speeches denoting an idea or message for a particular person while dolphins create whistles and sounds signifying an action for which another dolphin can understand, it can signal danger for their kind hence they should be alert or a prey is near at hand thus, everybody must prepare; depending on the whistle produced.