Vitality

Vitality is the overall wellness of a hominid. This is the life and the health of that hominid.

Overview
Each hominid has their own Vitality and this is determined by their experiences during game play and the age of that hominid. The better that the hominid is treated, the longer the vitality and viability of that hominid for game play.

Mechanics
Vitality is determined by three values - Life Expectancy, Stamina, and Energy.

These three values are interconnected and are represented by an overlapping set of circles in the HUD.
 * Life Expectancy is the bottom layer of the circle and is red.
 * Stamina is the middle layer of the circle and is yellow.
 * Energy is the top layer of the circle and is green.

It's not clear at first about Vitality but there are two concepts that are important:
 * Life Expectancy sets the maximum amount of Stamina available and Stamina sets the amount of Energy available.
 * Energy is used up first, then Stamina is used up, and then finally Life Expectancy is used up.

The overall Vitality level can be observed by watching the HUD circle as activities are performed, the more activities performed the more the green circle will slowly shrink. Once the green circle is taken over by yellow circle, it indicates that the Hominid is getting tired. Continue to perform activities and the yellow circle will slowly shrink to reveal the red circle of exhaustion.

Learning specific neurons reduces negative impacts to vitality.

Elder hominids lose half of their vitality due to their increased age but this loss is offset by them being immune to the Fear of the Unknown.

Neurons
The following neurons impact vitality.