[Hac-announce] The latest issue of Edge

[Thomas Platt]

"She (Laurie Santos) has investigated a number of topics in  
comparative cognition, including the evolutionary origins of  
irrational decision making and prosocial behavior."

What is the selective advantage in a negative, such as irrational  
decision making in both Capuchin monkeys and humans?  When I posed  
this to her, she suggested perhaps it once was an advantage.  Another  
possibility is that it may be a by-product of some more fundamental  
thing that does have a selective advantage.  An example of this might  
be the sickle cell trait:  When one has two copies of this gene, he  
or she can get severe anemia.  However if one is a carrier, ie,  
having only one copy of the gene, that person not only does not get  
anemia, he or she has a resistance to malaria.  There are many more  
of these carriers, and presumably there is selective advantage in  
being one.  The fewer number of individuals that have two copies  
represent the negative spin-off.

Tom Platt