|MadSci Network: General Biology|
The brain helps animals survive by providing a site where information is processed and the most basic activities necessary for survival such as breathing are regulated. The brainstem (the most primitive part of the brain) is the area where breathing is regulated for example. It is necessary for life. In more developed animals such as mammals there has been an increase in the size of the brain because having a more developed brain allows animals to process more information about their surroundings. Mammals are able to associate, for example, going to a specific watering hole and meeting a predator so that next time they go there they will remember that association and perhaps even avoid that site. In more developed mammals such as primates, the increase in brain size allows these creatures the ability to plan ahead and build tools, both of which provided tremendous advantages in terms of survival and in the case of our species has been selected for such that our brains have increased in size to a tremendous degree since our ancestors first appeared in Africa around 4 million years ago. References The Emotional Brain : The Mysterious Underpinnings of Emotional Life. by Joseph Ledoux People of the Earth : An Introduction to World Prehistory by Brian M. Fagan Neurobiology by Gordon M. Shepherd
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