Biology 484 – Ethology Chapter 7 – The Evolution of Feeding Behavior. Chapter 7 Opener: A bullfrog has many dietary choices to make. The Common Whelk (or Snail). 7.1 Optimal foraging decisions by northwestern crows when feeding on whelks. The maximum cost/benefit ration is seen at the arrow.
Chapter 7 – The Evolution of Feeding Behavior
The maximum cost/benefit ration is seen at the arrow.
Why would they not select the LARGEST mussels?
Time line showing how the bird will select to move to another foraging spot.
Feeding behavior can be influenced by other risks, such as that of predation pressures. In this case, it is snake scent.
This is an image of the phorid fly on the left. On the right is the end result of an attack on a fire ant, the main food item of this fly.
The forager ant is preyed upon by the phorid fly. But the phorid fly will only consume insects with a head size of 1.8 mm or greater. Hence, during predation times, the forager ant only sends out smaller (less efficient foragers).
Look for the efficiency of trotting versus galloping.
Because their phenotype differs, the two forms do not compete for resources.
Web ornamentation is seen in the more reflective regions (the zig-zag patterns) seen in this web.
Clay eating is useful for dissipating toxins the birds consume.
Test by von Frisch examining ability to learn direction from the dance in bees.
Test by von Frisch to test the communication of distance by the dance language in bees.
The blue bees were trained to think the food source was 70 meters away.
Note especially how the bees in the winter benefit especially in enviornments with oriented (unipolarized) light.