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What Makes a Mammal? Brains


What makes mammal brains so complex?
They are large relative to body size, and they have many folds, or convolutions. This products lots of surface area to support complex nerve networks. Also, only mammals have a neocortex, the six-layered structure responsible for highter information processing.

Part 1: Which of these brains does NOT belong to a mammal?

African Lion?
This is a mammal brain.

Bottle-nosed Dolphin?
This is a mammal brain.

Dogfish Shark?
This is a FISH brain!

Human?
This is a mammal brain.

Duckbill Platypus?
This is a mammal brain.

Part 2: Welcome to the brain lab.

Today we'll be looking inside these four mammal brains to see what makes them special. A good indication of intelligence is brain weight in relation to body weight, and animals with proportionally bigger brains show a wider range of complex behaviors.

Duckbill Platypus
The brain's smooth surface indicates fewer folds in the cerebral cortex, limiting the overall volume - and brain power.

Bottle-nosed Dolphin:
More intelligent mammals such as dolphins have highly convoluted brains compared to less intelligent animals.

Human:
Many folds and larger frontal cortex - as wall as the largest brain relative to body size - allows human complex behaviors.

African Lion:
Carnivores have bigger brains in relation to their body size than their prey - giving them the advantage to catch prey.

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