Describe5 marksStandard
A biologist studying a population of snails notices two traits: shell colour pattern (which occurs in three distinct forms: solid brown, striped, or banded) and shell width (which ranges continuously from 2.0 mm to 4.5 mm). The biologist hypothesises that different genetic factors control these two traits, and also wants to investigate whether environmental differences between two habitats affect shell width.
Describe the two types of variation (discontinuous and continuous) using this snail example, and explain the genetic basis of each type. Also describe how a t-test could be used to compare the mean shell width between snails from the two habitats.