Question

9. A ___________ life table would be most appropriate for a population of sessile barnacles, whereas a _________________ life table would be most appropriate for a population of baitfish such as herring. *

2 points

a. static; composition

b. cohort; stable

c. static; cohort

d. cohort; static

Answer 1

Answer-

Correct answer is d) cohort, static

A Cohort life table would be most appropriate for apopulation of sessile barnacles, whereas a Static life table would be most appropriate for a population of baitfish.

Life table provides data on the number of individuals alive in different age classes and age specfic mortality rates. Life table is of two types: cohort and static life table. Cohort life table follows a cohort of individuals from birth to death. It can be used to estimate the age specific probabilities of survival. It is useful for the population of sessile animals. On the other hand, Static life table follows age structure of a given population at one point in time. It is made from data collected from all ages at one particular time- it assumes the age distribution is stable from generation to generation. Estimating age specific mortality rates become very difficult using cohort life table for the population of moving animals who survive for many years. so, in this case static life table becomes very useful.