Evolution

• what is Darwin's theory of evolution?

  Natural selection- beneficial random mutations lead to more chance of survival and reproduction, meaning they are passed on and become dominant
• How did Darwin come up with his theory of evolution?

  visited galapagos islands 1835 and noticed differences between species, led to idea of funtionalism which says characteristics all have useful functions for survival
• What is adaptive radiation?

  when a single species rapidly evolves into multiple new species to survive, leads to little competition and diverse resources, driven by natural selection
• How did humans first evolve?

  • first hominids (human like apes) appeared in Africa
  • first one left Africa around 1.7 million years ago
  • rapid evolution of human brain and behaviour sets us apart
• What are humans closest relatives?

  • closest relatives are chimpanzees, gorillas, orangutans
  • we share 99% of our DNA with chimps
• Does brain size matter in evolution?

  large body does not equal large brain, neurons and complexity of brain is key not the size
• What complex functions can human brains carry out?

  colour vision, linguistic abilitities, opposable thumbs
• What is neotony?

  • slowing of maturation, allowing time for growth, important for large brain and complexity
  • not all neurons are coded at birth, so learning can occur from environment
• For what 2 reasons do we study non-human species?

  • similarities across species allow us to use animal models to understand our brains
  • comparative studies can investigate advantageous evolutionary features
• How is game theory used to explain evolution?

  • an economical mathematical model of strategic decisions
  • was applied in understanding evolution strategies (evolutionary stable strategies and price equation)
• What is the evolutionary stable strategy?

  says a good strategy must:

  • do better than competing strats
  • have atleast comparable benefits to other strats
• What situtations demonstarte the ESS?

  hawk-dove game and the prisoner dilemma
• What is altruism?

  behvaiour at a cost to oneself but benefit to others?
• why do we show altruism towards relatives if it opposes natural selection?

  • inclusive fitness: if species fitness increases, so does your own
  • shown in Hamilton's rule (rB>C) and Price's equation
• why do we show altruism towards strangers if it opposes natural selection?

  • reciprocal altruism: benefits with be reciprocated in similar situations for you
  • group selection: more cooperation helps to dominate selfish groups
• How can Meerkets be shown to display altruism?

  • meerkat stands guard while others forage
  • reduces guards survival chance, but benefits groups
  • means overall chances of survival increases