Evolution Humor

In Uncategorized on April 28, 2010 by Peter G. Klein

From The Onion, of course:

Man At Very Top Of Food Chain Chooses Bugles
April 26, 2010 | ISSUE 46•17

SOUTH BEND, IN—Despite having no natural enemies and belonging to a species that completely dominates its ecosystem, local IT manager Reggie Atkinson opted to consume the processed corn snack Bugles Monday. “I was in the mood for something salty and crunchy, and it’s a little early for dinner,” said the ultimate predator, whose ancestors’ bipedal locomotion, toolmaking abilities, and advanced spatial recognition developments allowed them to hunt animals 10 times their size. “These are original, but the other flavors are pretty good, too.” Acting on an impulse from an incredibly complex forebrain that has evolved over millions of years, Atkinson then took note of the Bugles’ amusing conical shape and placed one on each of his opposable thumbs like little wizard hats.


Lawlessness and Miles Davis

In Uncategorized on April 26, 2010 by bcnjake

Brandon seems to be making a lot of hay over the fact that any distinctly biological generalizations are contingent and therefore not universally true.  If they’re not universally true (i.e. the “rules” can be broken), then they cannot be laws.  But suppose you’re a scientific anti-realist like Cartwright, van Frassen, etc.  At this point, the whole problem seems to dissolve, since anti-realists don’t expect laws to be true; obviously false but explanatory generalizations are extrapolated from a limited set of causal histories.  Obviously, one might take exception to the “laws don’t have to be true” criterion, but assume that you’re okay with this.  Is there any other reason to lose sleep over the contingency thesis?  I can’t think of one, but I’m also inclined to endorse anti-realism.


A priori statements about biology

In Discussion on April 26, 2010 by Pete Abram

What kind of a priori statement about biology (or even physics) could be remotely interesting? Like Strawson said, an a priori statement is one which you can know is true from your couch, you don’t have to do any science. But if we’re not doing science, then it seems like the statement isn’t going to be biological in any interesting way.


how to screen off evolutionary game theory: which problems are solvable and which are not?

In Uncategorized on April 22, 2010 by wenwenfan

I had this question since Lynn asked about the Odd Man Out game in the seminar. I talked to Sheng about it, and we had some tentative answers, but I don’t know what other people think. I would like to hear from you about it.

In Yasha’s paper, he realized a problem for the Odd Man out game to model coalitions: the game predicts a much higher frequency of the break-up of coalitions. This problem can be interpreted in two ways: either it does not fulfill the empirical criterion (because its prediction is disconfirmed by emprical data) or there is some feature the game should incorporate. Yasha takes the second interpretation. This case seems the way Zac does in his paper about the Prisoner’s Dimma game. Zac found out that the Prisoner’s Dilemma game cannot yield a prediction of altruistic behavior, so he identified two features (namely, iteration and correlation) that should be incorporated into the game. As long as those features are considered, the game can yield a good prediction.

My question is: how do we know when the model simply fails to meet the empirical criterion and when it neglects some essential features it should consider? Sheng and I thought that perhaps we need some standard to judge when the empirical criterion is met and when it’s not. It may also boil down to the question what features a game should represent what it should not.


Contingency Readings

In Class matters on April 21, 2010 by Joshua Smart

Gentle Fellow PhilSciers,

The readings folder for next week contains three required readings. The primary one is John Beatty’s formulation of the evolutionary contingency thesis (ECT) which states that there are no distinctive laws of biology. For Sober’s response you can ignore the parts about Rosenberg. We’ll just be concerned with the first five page, where he is directly interacting with Beatty. Finally, Brandon provides a third view of the relationship between laws and biology, arguing on a rather different tack than Beatty or Sober.

There is one reading in the recommended folder–a recent piece by Morgan supposedly providing a counterexample to Beatty. It’s worth skimming to think about the ways in which we might learn that Beatty is wrong.


Odd Man Out

In Uncategorized on April 20, 2010 by Jenny

This may be a pretty naive question; so bear with me.

Yasha writes that the three-person Odd Man Out game is a better model than the Prisoner’s Dilemma or Stag Hunt for modeling coalitions (partly) because it can capture chimp behavior of coalition-forming.  But I wonder whether Odd Man Out can even do that.

In chimpanzee societies, the alpha male has the best reproductive success; so all the guy chimps want to be him.   To get an edge on the competition, some male chimps form agreements with other male chimps to team up and beat the rest out.  When one coalition is the only left standing, the two members duke it out.  The victor becomes the alpha male.  The other guy is beta.

But because Beta wants to be alpha, he forms a coalition with another male chimp, and together they overthrow Alpha.  Then, the other chimp becomes New Beta and Beta becomes New Alpha.  Unfortunately, then New Beta wants to be the alpha (so he can get girls), so he overthrows New Alpha with the help of another friend, and this process continues indefinitely (or until one chimp is beaten to death.  Gruesome.).

In the chimp scenario I’ve outlined, there are more than 3 players (Alpha, New Alpha, New Beta, & soon-to-be Newest Beta).  But Odd Man Out can only model three-player games (as far as I know).  So why would we think that Odd Man Out can explain such behavior?  Is it because only three players are being modeled at any given time?  But we could easily model four.  We could model soon-to-be-Newest Beta trying to convince New Beta to help New Alpha overthrow Alpha so New Beta can be the next alpha.  Why would we stop at three players?  Is the reason for stopping at three players any better than Skyrms’s and Binmore’s reasons for stopping at two?



Quick question on Zach’s Paper

In Uncategorized on April 19, 2010 by Leo

Since I think we’ll be talking mostly about Yasha’s paper tomorrow, here’s a quick question I had on Zach’s paper:

Zach’s paper distinguishes between two game-theoretic approaches: the static approach and the dynamic approach. The static approach focuses on characteristics of the strategy itself. The dynamic approach focuses on how players settle on a particular strategy. However, it is unclear to me whether or not these are actually two distinct approaches. Is it not the case that the dynamic approach merely specifies which of the equilibria already picked out by the static approach that players will actually converge on? That is, does the dynamic approach actually subsume the static approach, by first identifying all the possible equilibria, and then improve upon it by identifying a subset of those equilibria which will end up being chosen by the players given certain initial conditions?