In an Analysis of Hunting by African Lions, Biologists Filmed

Essay

In an analysis of hunting by African lions, biologists filmed prey captures from the safety of their vehicles. The capture of prey was divided into a sequence of events for study one of which is the stalk, defined as the reduction of predator-prey distance for prey that has been specifically located and the prey is unaware of or minimally alarmed by the predator. The investigators identified two types of stalk: (a) "crouching"--the lion is concealed and either the lion advances toward the prey or the prey advances (unaware) toward the lion, and (b) "running"--the lion is less concealed and advances toward the prey in a rapid manner.
Data on lions' stalks of wildebeests and zebras from a simple random sample of 159 kills appear in the table below. ​
a)By monitoring radio-collared lions for many years, biologists believe that the average stalking time among all prey is approximately 25.6 minutes. Do the data above provide evidence that for this population of lions the average time to stalk wildebeests and zebras is different from what was originally thought?
b)The same monitoring of radio-collared lions over the years suggests that the overall proportion of stalks that are the crouching type is about 0.87. Do the data above provide evidence that for this population of lions the proportion of crouching stalks of wildebeests and zebras is greater than what was originally thought?