###### [[lecture_Behavioral Evolution]] **Creator**:: [[Robert M. Sapolsky]] **Covers**:: [[Evolution]] **Link**:: [2. Behavioral Evolution - YouTube](https://youtu.be/Y0Oa4Lp5fLE) ## Notes - [[Biology]] can tell us a lot based off of our skulls - There is a inevitable logic to how [[Biology]] works because of the optimization of [[Evolution]] - [[sociobiology]] in 1970s -> [[Evolutionary Psychology]] - Basics of [[Evolution]] - Animals have traits - Those traits are heritable - Some traits are more adaptive than others - These traits lead to reproduction - This all leads to variance of traits in populations thanks to mutation - Wynn-Edwards and group selection is the idea of "the good of the species" which is pretty much incorrect and can be explained other ways - Three building blocks that abstract/replace [[natural selection]] and its derivatives - [[individual selection]] - behavior is how to preserve ones life and genes through reproduction ("selfish genes") - sexual selection would be a subset of this - [[inclusive fitness]]/[[kin selection]] - helping those you are closest related to in any situation - the more closely related you are with someone, the more genes you share with them - leads to us vs them thinking - [[Humans love to group eachother]] - [[reciprocal altruism]] - [[Evolution]] can lead to RPS stalemates where each organism has a weakness and a strength and their best interest is to work together - happens the most in [[bacteria]] - Major part: you aren't putting in more than you are getting - Works best in large, long-living, social species - selects for cheating, detecting cheating, and cheating in a way where you can get away with it - we are better at detecting cheating rather than kindness - [[Humans have decided to take advantage of an unjust world]] - lots of rules -> [[game theory]] - you scratch my back i'll scratch yours till you cut my back then ill cut yours - models to optimize theory i.e. [[Prisoner's dilemma]] - Highest payoff -> stab the other in the bad - Second highest -> cooperation - Third highest, sometimes punishment -> both stab - Worst -> you are the sucker - How to optimize? - Tit for tat - Cooperate as long as the other does - Forgives if the other person stops cheating - Vulnerability -> what if there is noise, where you think the other cheated but they didn't, leads to 50% less cooperation as you seesaw back and forth - Forgiving tit for tat - If you seesaw so many times, be forgiving to see if you can get back to cooperation - vulnerability -> can be exploited, taken advantage of - Transfer from tit for tat -> ftft once you trust your partner - Pavlov is the exploitive strategy - Perceived madness/signal noise examples - Vampire bats - feeding other bats kids - Sticklebat fish - Fish species changing sex - naked molerat - cooperative colonies - lazy members - plug the wholes during reproductive seasons - IRL strategies change - tournament species vs pair-bonding species/Parental Behavior discussion starting 1:20 - we are somewhere in the middle [3. Behavioral Evolution II - YouTube](https://www.youtube.com/watch?v=oKNAzl-XN4I&list=PL848F2368C90DDC3D&index=3) - In the 70s and 80s, we started to realize we weren't the only species that killed for pleasure - Infanticide comes from [[individual selection]], specifically lower class males killing other males youngs to free up females for themselves - this doesn't happen in families because of [[kin selection]] - Females solve for this by going into pseudo-ovulation to trick others in - [[Robert Trivers]], sex ratio fluctuation - [[Adelphic polyandry]] happens in cases where you are trying to avoid spliltting up you inheritance and thus your chance of reproductive survival - [[imprinted genes]] genes that work differently depending on which parent they came from, mainly comes from males and females not having the same reproductive strategy - [[group selection]] has snuck back into [[ethology]] in the [[founder effect]] ^igzkks - this is a way to jump start cooperation in a [[population]] - good explanatino at 1:00 - [[books_Darwin's Cathedral]] David Sloan Wilson book about calvinism - [[natural selection]] is the competition of individual items, whether those be genes, individuals, or groups - Three main aspects of Behavioral Evolution - Heritability - this is the piece most attacked by other fields - Adaptiveness - leads to fallacy that everything is adaptive or selected for - sometimes it is hard to see why something is adaptive - something may have been adaptive at one point - the term for this is [[spandrel]] - example: human chins, you can have a shortened muzzle on a primate head without a chin - Gradualism - [[evolution]] is a tinkerer - counter is [[punctuated equilibrium]] - There has been a [[Marxism|Marxist]] critique of [[Evolutionary Biology]] in that explaining things as "natural" or a evolutionary selection, often ignores a materialistic analysis next:: [[lecture_Molecular Genetics]]