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 Thomson's and Grant's gazelles from a sample of 151 kills appear in the table below. ​
a)On the basis of monitoring radio-collared lions for many years, biologists believe that the average stalking time for all prey is approximately 25.6 minutes. Do the data above provide evidence that for this population of lions the average time to stalk Thomson's and Grant's gazelles is different from what was originally thought?
b)The same monitoring of radio-collared lions over the years has suggested 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 Thomson's and Grant's gazelles is less than what was originally thought?