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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