Our
wild friends, whether they are herbivores or even rodents, have to forage for a
living. What happens when their foraging range vanishes? This could be due to
weather, invasion by another species, including the most greedy – man.
They
have to move to a new range, but what are the processes and what is the best
frame of mind for the foragers? Should they be pessimistic or optimistic about
their chances? Berger-Tal and Avgar have had a go at modeling the problem and report
out in the Public Library of Science (1).
The
classic model is based on the idea that the foragers should stick in a new area
until the forage quality drops to a certain threshold and then move on. Their
new model compares that pessimistic model (i.e. hang on to what you’ve got) to
an optimistic model that expects that greener grass is to be found on the other
side of the hill.
The
simulation shows that a good amount of optimism wins out. They explore more and
hence find more forage so that over the experimental lifetime, they consume
more forage.
Of
course, like everything in life, one might overdo it. Too much wandering might
not give enough munching time, but generally a good deal of optimism is a
winning strategy. The initial exploration may cost in munching, but the long-term
knowledge gain will always pay off in the end.
Maybe
we should all learn to stay optimistic as our forage comes under pressure?