Bottlenose Dolphin

The common bottlenose dolphin is arguably the most popular species of the Delphinidae family. Because they are found in both temperate and tropical waters, they are the most studied species; a majority of our Physiology knowledge about Delphinids as a family is based on bottlenose dolphins (Cozzi 2016). Because of the wide variety of habitats and climates that bottlenose dolphins inhabit, there is a lot of debate about how many different species are encompassed under the Tursiops Truncatus classification. However, in 1998, Tursiops Aduncus, commonly known as the “Indian-Ocean bottlenose dolphins”, was recognized as a separate species (Rice 1998). bottlenose dolphins usually range from 8-12 feet in length, range in color from

Morphological studies have shown that there are no fundamental differences between the Dolphin brain and the brain of terrestrial mammals. This implies that structures (such as the brain stem) are made up of the same components, but there may be differences in the size of individual structures (Cozzi 2016). As in many large animals the Neocortex – the part of the brain responsible for brain functions such as: cognition, sensory perception, and sophisticated motor control – is the dominant structure in the brain of Dolphins (Lodato 2015; Cozzi 2016). However, studies have shown that there are some differences in the way that bottlenose dolphins and primates process information. The Neocortex of primates, analyzes information in a demanding and complicated operation by a large number of single components (ex: stellate cells, columns, etc) (Cozzi 2016). On the other hand, Dolphins have a thinner Neocortex that seems to be programmed to do a “coarse and quick processing” of information (Cozzi 2016). Unlike what was previously believed, the Neocortex of Dolphins is not “primitive”, and recent research has described it as being highly evolved and extremely specialized in comparison with the brain of other mammals (Cozzi

Although there are no firm answers on the subject, there are a variety of different studies that reinforce the idea that bottlenose dolphins are highly intelligent mammals. One of the simplest measures that has been used to support this idea is the Encephalization Quotient (EQ). EQ is an accepted indicator of intelligence, it is the ratio of an animal’s brain size to its expected brain size based on measurements of other animals similar in size (Bearzi 2010). The bottlenose dolphin has an EQ of 4.14 - to put this in perspective, humans have an EQ of 7 and chimpanzees have an EQ of 2.34 (Marino 2004; Bearzi