Morgan worked with the tiny fruit files, Drosophila melanogaster, which were found very suitable for such studies, as:

(i) They could be grown on simple synthetic medium (ripe banana) in the laboratory.

(ii) They complete their life cycle in about two weeks.

(iii) A single mating could produce a large number of progeny flies.

(iv) There was a clear differentiation of the sexes-the male and female flies are easily distinguishable.

(v) It has many types of hereditary, variations that can be seen with low power microscopes.