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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




What if we make all of the bodies the same size?

What do you think will happen?

Here are some possibilities:

  • all the brains would also be the same size
  • changing body size won't make any difference
  • the more "intelligent" animals would have larger brains despite controlling for body size

What is your hypothesis?

Let's think about what we're doing . . . We're essentially "controlling for" body size by making all body sizes the same. In other words, we make all the animals' body sizes equal so that we can see if there are "true" differences in brain sizes. For example, to compare the brains of a dolphin and a squirrel we first need to determine whether a dolphin's brain is simply larger than that of a squirrel because the dolphin's body is overall much larger.

dolphin brain Is a dolphin's brain larger than a squirrel's squirrel brain
dolphin even when we control for body size????? squirrel

I don't know- let's make all body sizes the same size and see what happens...

Why should I care about this kind of comparison??

Huh? Can we start over?