Brain to body mass ratio (also known as the Encephalization Quotient or EQ) is a rough estimate of the possible intelligence of an organism.

Roughly speaking, the larger an organism is, the more brain mass is required for housekeeping tasks, such as breathing, thermoregulation, senses, motor skill, etc.The larger the brain is relative to the body, the more brain mass might thus be available for more complex cognitive tasks. This method, as opposed to the method of simply measuring brain mass alone, puts humans closer to the top of the list.

Dolphins have the highest brain to body mass ratio of all cetaceans. Sharks have the highest for a fish, and octopuses have the highest for an invertebrate. Humans have a higher brain to body mass ratio than any of these animals.

For example the ratio of brain weight to body weight for fish is 1:5000; for reptiles it is about 1:1500; for birds, 1:220; for most mammals, 1:180, and for humans, 1:50.

We (AS HIGHLY EVOLVED AN INTELLIGENT WE SEEM TO BE) do not yet understand the true nature and extent of neuroscience. Animal Cruelty is everywhere. So where is this intelligence we so proudly speak of in the human race. Do you see a dolphin (considered by many as the second most intelligent being on this planet under a human) killing humans for profit.

I say we are the beasts of this world; and unless alternative energies are found; we will leave a legacy of destruction behind us for our great grandchildren. Animal Activists; Human Rights Activists are the forward thinkers. They at least see the potential for change.