The Green Energy Circle
Energy is the primary ability that allows actions to be performed and is part of the vitality of a hominid.
Overview
Energy is depicted on the HUD at the bottom of the screen by the green circle and is the primary circle that appears. Performing any action requires some energy. Walking, climbing a tree, crafting a tool, etc. all require energy to complete. As energy is used up, the green circle will shrink. The more activities you do, the more your green circle will shrink.
Mechanics
Energy is determined by the Stamina level.
Energy automatically restores itself quickly by stopping any actions.
When the hominid runs out of Energy, Stamina will be spent to perform actions. At this point, it is heavily advised to stop and rest at the first chance you get. This will allow the green Energy circle to refill.
If the hominid uses more than 50% of his/her Energy reserves at once, some Stamina will be depleted but can be regained by resting for a moment.
If for some reason it is not possible to rest and restore Energy, it is possible to perform actions with Stamina but there is a cost. Overall Stamina will be reduced until it is restored by 
eating, 
drinking, and 
sleeping. The Energy reserve will be temporarily be lower until Stamina can be restored.
If the hominid is pushed past tired and depletes all of the Stamina, the red Life Expectancy circle will appear and will begin to drain. This is trading overall life to perform actions. Only in the most dire situations should this be done! If the hominid stops and rests, some Stamina and Energy will be regained, but the Life Expectancy that was drained will not regenerate.
Learning specific neurons reduces the negative impacts to energy usage and increases positive benefits with respect to energy.
Restoring Stamina and Energy
Restoring Stamina
Stamina and Energy can be replenished by eating, drinking, and sleeping.
There is a special pulsing yellow indicator that appears over the Vitality circle when restoring Stamina and Energy. This pulsating circle will indicate the need to (or not to) continue doing those activities. The pulsing yellow circle will flash to green when enough of that activity has been completed and is fully restored.
The green Energy circle will also increase in size while the pulsing yellow indicator is happening indicating that restoration is taking place.
Neurons
The following neurons impact energy.
| Image | Neuron | Neuronal Branch | Genetic Mutation? |
Description |
|---|---|---|---|---|
 |
Anabolism (BB WA 01) | Motricity | Yes | Less energy is consumed when performing actions. |
 |
Anabolism-Water (BB WA 05) | Motricity | Yes | Walking in shallow water requires less energy. |
 |
Anabolism-Water (BB WA 09) | Motricity | Yes | Walking in shallow water requires less energy. |
 |
Aquatic Locomotion (SW 01) | Swim | No | Swimming requires less energy and acceleration while swimming is possible. HOLD (button) to speed up while swimming. |
 |
Carrying Endurance (AB 07) | Ambulation | No | Moving while carrying an item with both hands requires less energy. HOLD (button) near a heavy or big item to carry it using both hands. |
 |
Carrying Endurance (AB 08) | Ambulation | No | Moving while carrying an item with both hands requires less energy. HOLD (button) near a heavy or big item to carry it using both hands. |
 |
Carrying Endurance (AB 09) | Ambulation | No | Energy loss while carrying items is minimized. HOLD (button) near a heavy or big item to carry it using both hands. |
 |
Climb Endurance (AB 04) | Ambulation | No | Climbing requires less energy. |
 |
Climb Endurance (AB 05) | Ambulation | No | Climbing requires less energy. |
 |
Climb Endurance (AB 06) | Ambulation | No | Energy loss while climbing is minimized. |
 |
Endurance (AB 01) | Ambulation | No | Moving requires a lot less energy. |
 |
Hydro-Dynamics (SW 03) | Swim | No | Swimming requires less energy. |
 |
Life Expectancy (LF 01) | Orrorin Tugenensis | No | Life expectancy has increased. More stamina and energy can be accumulated. |
 |
Life Expectancy (LF 02) | Ardipithecus Ramidus | No | Life expectancy has increased. More stamina and energy can be accumulated. |
 |
Life Expectancy (LF 03) | Australopithecus Afarensis | No | Life expectancy has increased. More stamina and energy can be accumulated. |
 |
Movement Endurance (AB 02) | Ambulation | No | Moving requires less energy. |
 |
Movement Endurance (AB 03) | Ambulation | No | Energy loss while moving is minimized |
 |
Nutrient Absorption (BB ME 01) | Metabolism | Yes | More energy is gained per food portion. |
 |
Nutrient Absorption (BB ME 02) | Metabolism | Yes | More energy is gained per food portion. |
 |
Omnivorous (OM 09) | Omnivore | No | Every serving of food consumed provides more energy. |
 |
Pain Endurance (AB 10) | Ambulation | No | Moving while injured requires less energy. |
 |
Pain Endurance (AB 11) | Ambulation | No | Moving while injured requires less energy. |
 |
Pain Endurance (AB 12) | Ambulation | No | Energy loss while moving with an injury is minimized. |
 |
Swim Endurance (SW 02) | Swim | No | Swimming requires less energy. |
 |
Well Rested Boost (NE 09) | Settlement | No | Less energy is burnt for all actions done after awakening, for a limited time. |
|
Well Rested Boost (NE 09-2) | Settlement | No | Less energy is burnt for all actions done after awakening, for a limited time. |