Evolutionary Bases of Behaviour-Adaptation Flashcards
Adaptation (definition)
def: adaptation refers to inherited behavioural and physical characteristics that have gradually (over generations) become more prevalent in a population because they increased the probability of survival or reproduction.
Adaptations in humans that are no longer useful: Taste preference (fatty foods)
*Because of the gradual nature of evolution, adaptations can linger in a population even after they no longer provide survival or reproductive advantage.
taste preferences:
-humans typically prefer the taste of fatty foods.
-was an adaptive preference in an era of hunting & gathering when calories were scarce.
-no longer a useful adaptation as calories are now abundant.
-maladaptive, as this taste preference leads people to consume too much fat, resulting in obesity, heart disease, etc,.
*maladaptive: behaviours or traits that are counterproductive
Adaptations in humans that are no longer useful: Fight-or-flight response (also applies to animals)
fight-or-flight response was developed to help our ancestors handle immediate threats (e.g., predators) by preparing the body to either face the threat, or flee.
-once useful for survival, now contributes to stress-related diseases and can be considered a maladaptive behaviour.
Adaptations:
pathogens & “behavioural immune system”
-pathogen prevalence can activate a “behavioural immune system” by triggering behaviours that reduce disease exposure, which promotes survival.
-pathogen prevalence causes a cultural pressure to conform; in countries where there are more pathogens, there’s a higher level of obedience and less personality variation.
example: going along with strict rules about food preparation can promote survival by avoiding pathogens.
Adaptation: rats & novel foods
-rats will only try one new food at a time, and in small quantity, to determine if that food contains toxins
-if the consumption of a new food is followed by illness, they avoid that food in the future
-these are highly adaptive solutions to the food selection problems faced by rats
Theodore Dobzhansky
-was a prominent geneticist and evolutionary biologist
-his work emphasized how genetic variation influences natural selection
-advanced the concept that natural selection operates on the population gene pool
