There have been plenty of studies on intelligence of people and animals over time. What some of this research is indicating is that dolphins rank #2 – behind only humans. This information is based on MRI scans of the brain that indicate they do have a high level of self-awareness. What is also interesting is that the brain of dolphins could prove to be quite vulnerable to traumatic experiences and suffering, just like humans.

Studies that have been done to determine overall brain power put humans as #1 and dolphins as #2. New research has been able to show that dolphins do have skills and forms of awareness that were once thought to be unique to only humans. The information determined from MRI scans also shows that the brain of a dolphin is about 4 or 5 times larger than it should be based on their body size.

This information is based on comparisons to other animals that are close to the same size. One of the leading experts in the world on dolphins is Lori Mario who is a Senior lecturer at Emory University in the area of Neuroscience and Behavioral Biology. She has done many MRI scans on dolphins. She also believes that using the brain to body ratio formula that dolphins would indeed by behind humans.

The findings of such studies have been presented by Marino in various capacities, including at the American Association for Advancement of Science. She does state that size is only one factor but that there is plenty of other data to support the claims about dolphin intelligence. The neocortex is the part of the brain that allows for higher levels of thinking to take place. This is also where emotional information can be expanded for dolphins.

There are studies on dolphin behavior that Marino and other experts have conducted that show these animals often can exhibit skills similar to humans. For example, being able to recognize themselves in a mirror. They are also able to identify abstract concepts, learn symbol based communication programs, and they also take part in cultural learning based on the group they belong to.

This information is why Marino doesn’t feel it is a good idea for marine parks to take part in teaching dolphins to perform or having them involved in dolphin assisted therapy. She and some other experts believe it could be harmful on a psychological level to them. They also worry it could give humans a false interpretation about the intellectual abilities of dolphins.

This information stems from the fact that when a person or an animal is highly aware of their circumstances they notice the differences between a good situation and a bad one. Negative feelings can occur for the dolphins due to them not being able to continue in a natural setting versus being in captivity.

The emotional elements of dolphins are very high, much like humans. There have been reports of dolphins becoming so upset during herding by boats that they can die of a heart attack. They can also die from exhausting due to their instinctive nature to flee from the situation. Those that are captured and then transported to captivity facilities can suffer a great deal of emotional trauma.

Diana Reiss, a Professor of at Hunter College in the area of Psychology also believes that Marino’s data and conclusions are solid. She plans on presenting similar information and to support this information about dolphins in an effort to make people more aware. Not only of their intelligence, but also of their emotional processes. 

Source: http://news.discovery.com/animals/dolphins-smarter-brain-function.html

There are many studies out there that compare the size of brains from one living thing to the next. What has been found is that the size of the brain for a human and a dolphin are almost the same. This is based on information that shows the evolution of the cetacean brain over a period of more than 47 million years!

Such studies have given experts information about the large size of the brain for toothed whales. Some of these species have abilities that have only previously been seen to exist in some of the Great Apes as well as humans. Now they have also been observed with some of the species of dolphins.

Brain of Pacific white-sided dolphin / Author: Tranletuha.

There are studies that show dolphins have the ability to recognize who they are when they see their reflection in a mirror. They are also able to communicate using symbol based programs and through concepts that are abstract in nature. Some researchers believe that the large size of their brain is what allows such intelligence to occur.

Yet what continues to be a huge mystery to the experts is the evolution of the brain over time. One of the largest fossil studies that has ever been conducted has been done by Lori Marino has several of her colleagues from Emory University in Atlanta. The study spanned 4 years looking over various collections in different museums.

The team used 66 different fossilized cetacean skulls that they found. Using CT scans, they were able to document the size of each of the brains. They were also able to document the body mass through the bones found at the base of each skull.

This study also included looking at similar data already collected on 144 cetacean skulls. This resulted in a total of 210 samples being looked at, with 62 species and 37 different families being represented in that total of samples. Find the EQ, or Encephalization Quotient, of each one was the purpose of collecting such data.

If you aren’t familiar with EQ, it is a representation of the ratio of brain to body mass. The scale works like this:

Large brain size – EQ greater than 1

Average brain size = EQ of 1

Smaller than average brain size = EQ less than 1

The largest of all creatures is humans with an EQ of 7. There have been two significant points in the evolution of cetacean that the EQ showed a significant jump. The first dates back about 35 million years ago. There were dramatic changes to the EQ as well as to changes in body size.

There are studies that indicate the development of larger brains was the result of the evolution for echolocation. This is the use of high frequency sounds that can be picked up as they echo off of various objects. Then the animals are able to interpret a variety of information from that occurrence.

It is believed the second dramatic increase in brain size occurred about 15 million years ago in the Delphinoidea super family. This includes narwhales, belugas, dolphins, and porpoises. The information from fossil records suggests that these increases were significantly more than that of humans or great apes.

The findings of this study are believed to be one of the few that have helped us to gather such information from the fossil records. Such research is time consuming but it is also very important as well as interesting. If you are interested in reading more about the research this team has done, it will be in The Anatomical Record, December issue.

Source: http://dsc.discovery.com/news/briefs/20041108/dolphin.html