Dolphins

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The dolphin is one of nature’s most impressive of aquatic creatures. The way they work in pods to both achieve goals for survival and social harmony are quite impressive. Perhaps their skill is derived from their enormous brains which are found to be even larger than humans. Their brains are however not their most outstanding characteristics for they also possess outstanding hydrodynamics, sonar, and relational abilities that set them apart from other marine life.

Introduction to Dolphins

Dolphin anatomy is incredibly well adapted to their life in the ocean. Dolphins may live in either salt or fresh water although the majority live in saltwater somewhere near the shore (Bioexpedition). The need for ocean preservation to sustain these animals is paramount. The size of the dolphin is highly varied among fish with sizes as little as 4 feet or as great as 30 feet long. This range in pounds gives some dolphins just 90 pounds or as much as 11 tons (Bioexpedition). The coloring of the dolphin such that they match their oceanic environment. Thus they typically have a grayish blue color which will vary in tones of light and dark. Their skin layers will usually be 10 to 20 times wider than terrestrial animals, a characteristic that permits them to peel and flake of sheets of old skin to be replaced quickly by older ones (Bioexpedition).

The Dermis, or skin layer, of a dolphin is specifically designed for their speed and play in the water. Their skin is free of any ridges or hairs that would slow them down while they swim. The overall structure of the dolphin is streamlined for quick movement even over the course of a long period in time (Bioexpedition). The tail end of the dolphin is known as it’s fluke and this fluke allows them to propel through the water with great thrust. The pectoral fins are also used to give them the ability to change their direction at will (Bioexpedition).

The Dolphin is also unique in that they have a blowhole which aids them in breathing. As mammals, dolphins do not use gills but rather have lungs like terrestrial animals which require them to regularly surface for air. Because of this need for regular surfacing, Dolphins consciously breath unlike humans who often if not always breath unconsciously. This is done through the dolphin’s nostrils which are located on the top of their head (Schaefer). Having a nose on the top of their head permits easier swimming and breathing than having them in the front with the added benefit of permitting breathing without actually exiting the water. The breathing patterns of the Dolphin are unique as well. An average dolphin can inhale in just .3 seconds through the blowhole located on the dorsal side in the swollen gland part of the head known as the melon. This orifice can be voluntarily closed and opened at will for the direct expulsion of mucus or water and also may be used for the modification and amplification of their various noises (Schaefer). With their inhalations, dolphins may hold their breath underwater for 15 minutes long in some cases although the average time is 7 minutes. Their success underwater is partially because their blood has a higher concentration of red blood cells, something that helps with storing oxygen (Shaefer). Also, the fact that the dolphin may voluntarily slow his heart from 100 beats a minute to just 10 significantly increases their oxygen conservation.

Another fantastically adaptive and intriguing aspect of dolphins are their penises which are unique among the nature kingdom in several ways. The male dolphin’s is actually dexterous meaning that it can be used a multi-tool appendage with the ability to sense, grope, and sex other objects (Gayomali). This gives it some of the capacities and purposes as the average human hand. Furthermore, the appendage is retractable as well and therefore will not hinder them when speed is critical. It may be this appendage which gives the dolphin its notorious sexual appetite, a past time they are known to take out on other sea animals, like turtles, and even inanimate objects (Gayomali).

Possibly even greater however is the Dolphin’s sonar ability, a function they have used to hunt, communicate, and even detect enemy submarines. Sonar abilities come from the use of sound waves that are sent out by the dolphin and then return to them after having bounced off some object. Depending on the return vibration, frequency, and amplitude of the sound, the Dolphin can understand a remarkable number of important features regarding the environment which have key survival value. According to some news reports, dolphin teams have managed to detect enemy submarines even within very murky water (McGrath). The process for echolocation entails first clicking through the nasal passage which is then focused into a beam shape before ejected into the water. The sound wave then is bounced off an object which will then be ideally reabsorbed by the dolphin through their jaws. The jaws possess a layer of fat that move from the side of their face into the inner ear, which in turn connects to the brain where size, shape, and even material can be discerned (McGrath). Thus with their sonar, blow holes, and physical structure, the Dolphin is extremely equipped for a rich and healthy life in the waters as some of the oceans’ foremost mammalians.

Dolphin Intelligence

Dolphins are renowned for their intelligence. Stories abound of dolphins mastering new tricks and acting in ways humans find both amusing, intelligent, and surprising. For instance, Kelly, a dolphin at the Institute for Marine Mammal Studies in Mississippi, has the reputation for teaching both her peers and trainers abilities that net her more food. In one experiment, Kelly actually managed to reverse train the experimenters to bring her more food while exerting minimal effort. Furthermore, she is known to have baited the local gulls into her pool to net even more fish which was quickly then mastered by her calf and then dolphin friends. The dolphins have been gull-baiting ever since with apparently a great deal of enjoyment (Rohan).

Even with such impressive stunts, the intelligence of the dolphin is a controversial topic. Scientist have found that their brains are as much as 25% heavier than that of the average adult human brain (Rohan). Technically speaking however the typical way of comprehending a species intelligence is through an analysis of the body to brain weight ratio known as the “encephalisation quotient” (EQ). Human beings have a brain weight ratio of 7.4 on average. River dolphins have an EQ of 1.5 however bottlenose dolphins carry an EQ of 5.6, a figure more than doubling human being’s closest ancestors, chimpanzees who have a ratio EQ of 2.48 (Rohan). The EQ while useful does not entirely and/or accurately represent the workings of the brain and thus they may be way smarter or dumber than is presently known.

One of the most impressive of dolphin catching acts is the ‘art’ of tail whacking. Swimming in pods, a group of dolphins will use their tail flukes to drum up fish with a stun effect that lifts them 9 meters in the water so that they can then be picked off at the surface (Rohan). Dolphins also are known to disguise themselves with seaweed when hunting fish. Furthermore, Dolphins in Galveston Bay Texas have been known to swim into the shrimp nets to take live fish and then wriggle out without being killed, a skill that entails expertise in both mind and body (Rohan). Tools are not beyond the dolphins either. Researchers once saw a dolphin drive a moral eel out of the safety of his crevice through prodding him with the bone of a scorpion fish that he himself killed. Additionally, Dolphins in Australia have been known to place sponges over their snouts as they hunt stonefish and stingrays over the shallower seabed (Rohan).

Dolphin Communication

The success of the Dolphin may be traced to their linguistic capacities. Although some researchers doubt the intelligence of the squeaks, whistles, and whales, there are many who still argue that each sound is actually a form of complex system of communication known as referential signaling. Referential signaling means that they use various communication signals at visual, auditory, or physical levels that correspond to various ideas they may wish to convey including their mood, age, sex, and/or food (Oberhaus). Their utterances, although lacking linguistic intricacy found in human languages, is nonetheless a rather ingenious model for conveying abstract information in an strange medium, the ocean’s water. The method for recording and decoding the dolphin’s language is achieved through the Cetacean Hearing and Telemetry Chat (CHAT) device, a submersible computer that interfaces the essential communication noises and gestures made by dolphins (Oberhaus).

Most intriguingly, the complexity of the Dolphin language structure has been used to enhance efforts to speak with extraterrestrial races. Ever since the Order of the Dolphin began in 1961 with 12 of some of the world’s brightest minds including three Nobel laureates, such as Carl Sagan and John Lilly, there has been a consistent and hard headed research initiative into the possibility of Dolphins teaching humanity how to swim through the vastness of space responsively enough to discern and return alien signals of communication (Oberhaus). The Order of the Dolphin has been hard at work for sometime now and even has connections with SETI, the well-established and respected Search for Extraterrestrial Intelligence.

It was from a member of the Order, Laurance Doyle, that the coherence of dolphin language was first realized and accepted as science. Through the application of Zipf’s law, a semantic principle derived from human languages regarding the frequency of commonly used phrases and words, it has been realized that the overall linguistic patterns of dolphins is similar enough to humanity’s own that they likely possess a great deal of intelligence (Oberhaus). In brief, Zipf’s law holds that certain words occur in meaningful patterns based upon their use, such as ‘the’ being the most common word, used in 7% of language, and ‘of’ the second most common in 3.5% ‘of’ word use. When graphed, this ratio of use makes a slope of -1. in word use; a rate also observed in dolphin’s various noise and signals (Oberhaus). The rate discovered by Zipf’s law is practically only demonstrated in Humans and Dolphins, and not in other less intelligent forms of life such as squirrels or cotton plants. Thus, SETI may utilize the research gained in studying Dolphins to similarly analyze incoming messages from space with the theory that an intelligent species will likely work with Zipf’s law too(Oberhaus).

Conclusion

The Dolphin is as majestic as it diverse. An enormous range of intelligence, characteristics, and size are observed in this complex creature which is even helping scientists to make sense of extraterrestrial communication. In sum, they have a loveable, vivacious, gregariousness, and evolutionary aptness to them which is incredible and impressive.

Works Cited

Bioexpedition. Dolphin Anatomy. Dolphin-world, 2014. Web. July 7, 2016. http://www.dolphins-world.com.

Gayomali, Chris. The 12 Weirdest Animal Penises on Earth. The Week, 2013. http://theweek.com/articles/474417/12-weirdest-animal-penises-earth-updated.

McGrath, Jane. How can dolphins disarm sea mines? How Stuff Works, 2016. Web. July 8, 2016. http://animals.howstuffworks.com/mammals/dolphin-disarm-sea-mine1.htm.

Oberhaus, Daniel. Dolphins are helping us hunt for aliens. Nautilus, 2016. Web. July, 7, 2016. http://nautil.us/blog/dolphins-are-helping-us-hunt-for-aliens.

Rohan, Anuschka de Rohan. The Guardian, 2003. Web. July, 7, 2016. https://www.theguardian.com/science/2003/jul/03/research.science.

Schaefer, Larry. Blowhole & Breathing. Understand Dolphins, n.d. Web. July 7, 2016. http://understanddolphins.tripod.com/dolphinblowholeandbreathing.html.