evolution

• evolution is the gradual development of new species from existing species over time
• evolution happens through natural selection
• natural selection 


  the gradual process by which heritable traits become more or less common in an environment
• mutation - spontaneous change in DNA sequence that may result in a different phenotype
• sexual selection is the process by which individuals with traits that increase their reproductive success are more likely to survive and reproduce and is a form of natural selection
• environment of evolutionary adaptiveness (EEA)


  the conditions that prevailed int he environment at the time that a species was adapting in response to
• evolutionary psychologists would argue that the brain evolved much like the body and that some aspects of human behaviour result form evolutionary adaptations that served a purpose in our ancestral past
• the structure and function of our brins have evolved to to serve an adaptive function in the environment of evolutionary adaption (EEA)
• unlike our genetic makeup our environment has undergone rapid change leading to us having hardwired behaviours that are no longer useful
• consuming high calorie foods would have been an adaptive function in the past in order to prepare for famine
• in evolutionary terms success is measured by the production of offspring that survive to reproductive maturity
• in the EEA successful males were physically bigger and stronger therefore being the most capable of providing food, protecting mates and offspring
• males who were naturally more aggressive when their resources where threatened or when hunting would have an adaptive advantage as they would be more prepared to attack others and take resources to provide for their family
• successful females chose mates with favorable characteristics and good genes as they are more likely to provide better recourses
• females would be less physically aggressive as it would be an evolutionary disadvantage as they would spend long periods of time pregnant, breastfeeding and and looking after children to ensure their survival
• female aggression is less physical and more emotional and verbal
• Buss (1999)


  females would be in competition for mates and would denigrate other females to potential mates to make the other females look less attractive
• Harvey, Spencer, Wenzel (2004)

  sexual jealousy is often a major cause of aggression in males and couples. males may be biologically driven to protect their reproductive resources
• Mazur (1983)


  found that there is an increase in intermale fighting around the time of puberty when there is a rapid increase in testosterone. this shows support for testosterone levels being associated with aggression
• the evolutionary theory is a post hoc argument as the theory is developed to fit the facts and the ideas cannot be scientifically tested