<span>Dreams for Survival Theory
</span>
The dreams-for-survival theory states that dreams have helped humans evolutionarily by simulating threats, thus preparing people to fight for survival. It is also called the threat simulation theory.
<span>The theory stems from the notion that many dreams are stressful. When humans are dreaming, they are often dreaming of situations in which they need to fight to survive. This essentially provides practice for survival instincts and functions as a defense mechanism.</span>
Their limbs are homologous structures, which means that they are all inherited from the common ancestor of the tetra pods.
<em /> I believe it's gravity.
