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Compare Brains

Compare Brain and Body Sizes

Compare Brain Structures- Slices and Slides

The Neuron- Up Close and Personal

The Question of Intelligence
  1. absolute size
  2. brain/body size
  3. cortical folding
  4. neocortex
  5. gray matter/nerve cells
  6. specific brain structures

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looking at brains

What if we look at specific brain organization and structure? It is important to note that there are regions in mammals for which there is no corresponding area in non-mammals and vice versa. This may or may not have implications for behavioral complexity. The signifiance of anatomical data depends on the relation of structure to function. Thus, we'll focus on mammalian species predominantly.

What if we made a comparison of the size of brains (brain weight) and brain parts, based on indexes that directly reflect size differences (ratios) in species of equal body weight? Well, since I myself could not do the study, we will look at someone who has

S. Heinz et al. isolated the a large number of brain structures from 3 different Families of primates, including structures like the medulla oblongata, cerebellum, and neocortex. They also found the total brain size of these animals. They found that the relative size of some brain parts shows strong differences between individual primate species. Going the spectrum from prosimians to man, they found the greatest differences in the size of the neocortex; the next greatest differences were found in the cerebellum; and the least differences were found in the medulla oblongata and the olfactory bulb. (Heinz, 15).

In other words, these researchers discovered that even among closely related species, there are slight differences in terms of the structure of the brain.

Does this give us relevant information about intelligence/ behavioral complexity? What about evolutionary trends? What can we hypothesize about the fact that lower primates have smaller amounts of neocortex than higher primates and man? Perhaps this suggests that human primates are more advanced than lower primates due to their relative brain structure sizes? What about accounting for ecological or behavioral adaptations? Differences in relative size of brains and brain parts may reflect differences in these adaptations. However, simple interrelationships are hard to identify as they can be masked by a wide spectrum of factors.

Why don't we actually look INSIDE the brains of all these animals??

Great idea! I want to look inside some brains!

Go back to comparing brains

Huh? Can we start over?