Last week (because I'm a week behind on these!) we looked at altruism and cooperation, behaviors that appear to operate against the selfish behavior we often assume is necessary for reproductive success. From there we also explored parenting, where individuals often go to great lengths to care for their offspring, but also sometimes consider trade-offs between current and future reproductive opportunities.
In lecture, the TAs modeled the Prisoner's Dilemma (click the link if you're unfamiliar with it) with candy prizes rather than jail time, and then I held a student tournament. Normally the Prisoner's Dilemma is set up something like this:
|Cooperates||Defects||Cooperates||6 months | 6 months||0 years | 10 years|
|Defects||10 years | 0 years||3 years | 3 years|
It was loads of fun, but interestingly, the way I set up the game seemed to lead to cheating being the best strategy. I just couldn't get any of them to brave cooperating, save one pair who were close friends. This is likely because the punishment for cheating wasn't strong enough, and/or the reward for cooperating wasn't great enough. I set it up like this:
|Cooperates||Defects||Cooperates||3 candies | 3 candies||0 candies | 5 candies|
|Defects||5 candies | 0 candies||1 candy | 1 candy|
If "both defect" was set up so that students would LOSE candy from their stash, perhaps it would have turned out differently. I also think this game is very different when it feels like the stakes are about winning (candy) rather than losing (jail time). Either way, it was a great way to learn about and understand the conditions under which reciprocal altruism could evolve.
If you'd like to play around with the game yourself, there are a few online Prisoner's Dilemma games: here is one of them.
Altruism and cooperation
Two cool PLoS papers just happened to come out on cooperation in the last few weeks. Cooperation under indirect reciprocity and imitative trust by Saavedra et al looks at human behavior. They examine conditions under which reciproal altruism can evolve even when interactions aren't iterated -- that is, when people don't encounter each other that often, but still act altruistically towards each other.
Chadefaux and Helbing look at different variables that may promote cooperation, in How wealth accumulation can promote cooperation. They use the Prisoner's Dilemma model, but add a twist: players can accumulate wealth, and are able to invest their wealth in later interactions. Under these conditions, cooperative strategies dominated (unlike in my class exercise, where the temptation to defect was too strong!).
We discussed kin selection as one of the factors that promotes altruistic and cooperative behaviors among individuals. Recently some heavy hitters from within evolutionary biology have dusted off the ole' group selection vs. kin selection argument, and you can read more here: Kin Selection Dead?
A wonderful bridge between these two topics (which is the reason I taught them together) can be found in this post at the old Neuroanthropology digs: Evolution of altruism: kin selection or affect hunger?
The above link should give you a sense of why I covered parenting in the same lecture we did the Prisoner's Dilemma. Parenting is incredibly costly, and while there is a reproductive benefit, the mental and physiological strain is substantial. Some days the cons seem to outweigh the pros. Yet many, if not most, people eventually become parents. Are we driven by an innate desire to pass on our genes? Are we mindless drones of culture, which sometimes seems to value parenting, and even implies it is inevitable and necessary?
One thing seems pretty certain: in the human lineage, if we didn't invest in our children and parent them heavily, they would not survive. Kids are dependent on the help of others through adulthood. This isn't just because of the transition in industrial cultures to have to go to school for long periods of time before getting a job: many individuals don't master the skills necessary for survival in foraging societies until they are in their thirties or forties.
Parenting isn't purely altruistic, because of the fact that we are usually related to our children. And there are significant rewards to having children. But some psychological studies suggest parents aren't actually all that happy. Psychologist Dan Gilbert also offers his perspective.
Perhaps it is true that we outweigh moments of extreme, overpowering love, like the day this summer that my daughter Joan, for no reason at all, stopped what she was doing and felt compelled to hug me and whisper in my ear, over and over "I love you Mommy, I love you Mommy," compared to my Tuesday evening this week when, after we voted, she decided to have an all-out temper tantrum at the voting site, and for the whole walk home. It seems like we need to think about how we measure happiness, then, before we simply decide that parents are not happy (or that non-parents are not happy).
A few last good links on parenting. Greg Laden's great series of Falsehoods contains this one: A baby is not the biological offspring of its adoptive mother. Puts the kin selection concept of parenting into perspective. I also want to recommend a few websites: the blog parenthropology, and the site Parenting Science (which my students will recognize, as they had a reading from it for this week).
Then there is also the website for Aware Parenting, a type of parenting that I like and use with my child -- check out the articles. Parent Effectiveness Training and Playful Parenting are other resources that I have found useful, particularly in my darker moments when I feel stuck. Last, some perspectives on the Mommy Wars to help you think about how and why parents (particularly from industrialized populations) can be so judgmental of each other.
Random this week
Not too much to share this week. Neil deGrasse Tyson's speech earlier this year on how Learning is Empowerment. And, two TED talks that are marginally related to this week's concepts: The hidden influence of social networks and On the tribes we lead.
Speaking of altruism, have you checked out my DONORS CHOOSE GIVING PAGE? Imagine the massive effect a few minutes, and five dollars of your day, can have...