In order to survive, humans require a minimum of one-third of the oxygen content at sea level.Using the figure below, what was the most recent point in Earth's history at which a human could (barely) survive unaided on the surface? 
Definitions:
Own Groups
The social groups to which an individual feels they belong, often leading to favoritism toward group members and bias against outsiders.
Social Learning
A theory positing that people learn from one another, via observation, imitation, and modeling.
Attitude Formation
The process by which individuals develop and change their evaluation of objects, people, or events, based on factors like personal experience, social influence, and genetic predispositions.
Cognitive Appraisal
The process by which an individual evaluates and interprets an event or situation in terms of its significance to their well-being, influencing emotional and stress responses.
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