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A concept in evolution linking survival of the fittest to natural selection. Traits or behavior benefiting the survival of an organism or species will thrive by having an advantage in being passed on to future generations.

The following situations are examples of survival value in action:

• Primate A is afraid of snakes. Primate B is afraid of armadillos. Primate A has a better chance of living longer and is therefore more likely to produce offspring and pass on his or her phobia.
• Members of animal pack A develop a ritual that ensures only the strongest individuals mate. Members of animal pack B reproduce randomly. Pack A will become more resilient and more likely to survive the elements, thus passing on their ritual.
• Tree A produces seeds wrapped in a nutritious filling. Tree B does not. Hungry animals will give tree A an advantage in producing more offspring over a broader area.

In the examples above the behavior or trait in the A group has a higher survival value than group B. This is partially why more people are afraid of snakes than armadillos, male rams headbutt each other for mating rights, and peach trees grow more than just the pits.

Survival value can explain a range of behavior, from many animals' compulsion to run away to die (to save others from infection) to the Coolidge effect to the maternal instinct.

However, evolutionary principles are more intricate than such a general rule; survival value cannot explain everything throughout the history of evolution.

• Genetic anomalies, such as albinism, occur despite having a low survival value.
• Abnormal behavior and other disorders also persist despite having a low survival value -- although the concept of survival value may be stretched to explain them (for example, one could argue that serial killers are acting on a triggered evolutionary safeguard against overpopulation).
• Technology has impacted what has survival value. For example, due to the advent of corrective lenses, 20/20 vision has a smaller survival value than it once did.
• Complex emotional states are not easily explained by survival value. The survival value of the ability to feel pain, for example, is easily understood, but the concept of guilt is more complicated.