Question

What is an effective population size? Can it be larger or smaller than the actual population size? Why? 


What is the ecological argument that shows that body size and population size should in general be negatively correlated? Is the argument sound? 


Answer 1

1) Effective population size is the number of individuals in a population who contribute offspring to the next generation.

Effective population size helps us quantify how a particular population will be affected by drift or inbreeding. Effective size takes into account not only the current census size of a population, but also the history of the population. Effective population size is the size of an “ideal population” of organisms .There is no such thing as “the effective size” of a population. Different effective population sizes help us estimate the impact of different forces. The effective size you estimate will depend on the scientific question you are trying to address.

2) Speciation Rates, Differential Extinction Rates, Dispersal Ability, Interspecific Competition, will clear the ecological argument that shows that body size and population size should in general be negatively correlated