Animal behavior .txt

-Natural selection generates behavioral responses, maximizing fitness by balancing benefits against cost ( Evolutionary Economics)

• -makes assumptions explicit
• - generating testable predictions
• - if the model doesn't fit they can suggest new hypothesis

- behavior may not always be optimal

• -Decision variable (Behavioral option such as pursuing or not pursuing the prey)
• -currency( must correlate with fitness such as maximizing rate of net energy intake E/t)
• -assumption and constraints
• simplify to enable solution, but capture essence of problem
• intrinsic ( limitation in ability)
• extrinsic( imposed by environment, prey density of presence of predator)

• -pursue pray or not should it attack or search for another prey
• - maximize rate of energy intake
• - assumptions to consider is if prey are encountered sequentially, time spent searching and handling are independent, lions have perfect knowledge they know the profitability and density of prey.

• -E1 is energy provided by prey 1
• -h1 is time required to catch and consume each prey type
• -s1 is search time required to find prey. Search time depends on relative abundance of prey)
• - profitability = E/h

• current prey can be caught and eaten only if energy gained exceeds that expected if searching for the alternative.
• E Current/ h current > E other/ (S other+ h other)
• If Gazelle encountered
• E tg/h tg > E wb/ (S wb+ h wb) so S wb > (E wb / E tg)(h tg)- h wb

• always eat the most profitable prey type
• include the less profitable prey if S1> (e1/e2)h2- h1 where e1>e2
• also note that inclusion of less profitable prey does not depend on its abundance ( dictates search time)
• specialist in prey type 1 should switch and become more generalist both suddenly and completely when prey type one becomes rare.

Around 25 kj

In low density area , where the large prey and small prey frequency were the same, both were consumed equally, where as in the high density 3 there was a smaller portion of the large pray and larger portion of small prey , it was predicted that they would most likely consume the bigger prey , the result suggested the same thing but it was a little below predicted.

• to include prey the profitability must exceed the net profitability of all higher rank preys.
• E3/h3> (e1+e23)/ (s1+h1+s2+h2)

• -mistaking prey type
• -lack of complete information
• -simultaneous encounter with multiple prey
• - simple sampling rule for estimation encounter rate
• -variation in prey size or difficult to process prey

Digestive pause.

as time spend in a patch goes by gain in food increases to a certain point and then starts leveling off.

• when is it time to leave
• maximizing profitability
• time spent searching in patch and traveling between patches are independent
• foragers encounter patches sequentially
• energy gain in a patch and patch location are known
• also energy gain in patches shows diminishing return

optimal search time in a patch is greater when travel time between patches is longer

• consider different currency ( maximize time and efficiency and minimize risk of starvation)
• include additional constraints (predation risk, min nutrient requirements and avoiding toxins)
• consider simpler decision rules