… as, according to the paper you linked, do rats. Good point. Can this be explained in similar ways? A pigeon or rat’s environment could surely provide uncertainty about whether a future reward will be delivered at all. Time and energy spent keeping track of a future reward might still be a significant cost. Could these factors have selected for neural circuits that just apply a hyperbolic discount function as a default in the absence of specific reason to do otherwise? This does seem to be evidence suggesting the answer might be yes.
Naturally-occurring cases where hyperbolic discounting leads to suboptimal solutions are relatively rare, and at least one seems to have evolved a patch.
Pigeons also discount hyperbolically.
… as, according to the paper you linked, do rats. Good point. Can this be explained in similar ways? A pigeon or rat’s environment could surely provide uncertainty about whether a future reward will be delivered at all. Time and energy spent keeping track of a future reward might still be a significant cost. Could these factors have selected for neural circuits that just apply a hyperbolic discount function as a default in the absence of specific reason to do otherwise? This does seem to be evidence suggesting the answer might be yes.
http://lesswrong.com/lw/1ss/babies_and_bunnies_a_caution_about_evopsych/1o4d
Naturally-occurring cases where hyperbolic discounting leads to suboptimal solutions are relatively rare, and at least one seems to have evolved a patch.