In a relatively small iguana population the allelic frequency is tracked for three generations. webbing is a recessive allele; no webbing is the dominant allele. during one very rainy spring and summer, a flood washes all the iguana without webbed feet out to sea. by the fall, and three generations later, you have the gene pool seen here. this is an example of

This is an example of founder effect.

Explanation:

Founder effect may be illustrated as the loss of genetic variation in a novel small population originated from the original population. The concept was initially presented by Ernst Mayr. It can be seen that genetic diversity has got reduced in the population of iguana due to the result of the flood that has washed all the iguana without webbed feet into the sea.  

The new population has got inclined from the small iguana population. Thus, the iguana population is regarded as an illustration of the founder effect.  

when it is at an intermediate population density