Absolute Brain Size

What follows is a list of total brain size in a number of different animals.  It is important to mention that if
animal A has a larger brain than animal B, animal A is not necessarily more intelligent.  There are actually
many reasons why this might be true.  Many scientists believe that to find out how smart an animal is we must
determine the size of its brain relative to other animals and then correct for body size.  This is important
because larger bodies, along with the muscles and nerves needed to control them require larger areas of the
brain dedicated to coordinating muscle movement.
Not only do different animals vary in the amount of brain tissue that they have for controlling muscle
movement but they also vary in the amount of tissue for a variety of brain areas, each with different functions.  
For example apes have brain areas that allow them to process vocalizations from their friends, and also an
area for producing their own audible sounds.  These brain areas are in the same place in the brain, and have
some of the same structure in humans, but in us, they are much larger, and allow the acquisition and use of
language.  Each animal species has a unique pattern of brain structure, because each species has a
different way of getting food and finding mates. Keep these things in mind as you peruse the list below:

Humpback Whale             6500
African Elephant               5700
Bottle Nose Dolphin        1400
Human                                1350
Walrus                                1110
Hippo                                    700
Gorilla                                   512
Polar Bear                           500
Orangutan                           420
Chimp                                   400
Caribou                                290
Tiger                                      260
Lion                                       240
Seal                                       250
Tyrannosaurus Rex          200
Baboon                                180
Jaguar                                  150
Warthog                               125
Wolf                                       120
Spider Monkey                   100
Coyote                                   85
Gibbon                                   80
Capuchin                              65
Macaque                                60
Howler Monkey                    50
Raccoon                                40
Anteater                                 25
Porcupine                             20
Crow                                       10
Loris / Lemur                        10
Alligator                                 10
Armadillo                              7.5
Marmoset                           7.25
Shrew                                  4-.5
Opossum                             4.8        
Tarsier                                  3.5
Guinea Pig                           3.3
Norway Rat                         2.0
Coelacanth                          2.0
Eel                                           .6
Goldfish                                 .4        
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