Whenever Paramecium aurelia and Paramecium caudatum are placed into the same culture and given a constant supply of food under constant conditions, P. aurelia will always outcompete P. caudatum, which eventually dies off. What factors prevent P. caudatum from surviving in this situation?

The competitive exclusion principle.

Explanation:

In Competition, there are few resources in a habitat to be obtained by the different species resulting in intracompetition and interompetition.

The competitive exclusion principle emphasizes on the fact that two species would not stay in the same type of niche in a habitat. That is to say, varying species would find coexisting not feasible in a community if there is competition for the limited resources.

The attached image gives clarity to this principle. Paramecium aurelia and Paramecium caudatum grow best separately, but not in the same media.

In this case study, involving two protozoan species, Paramecium aurelia and Paramecium caudatum. If the two are cultured separately in the laboratory, they both grow very well. But when cultured together in the one test tube (region), P. aurelia outshines P. caudatum for food, this will result in to the latter’s gradual termination.

Let's turn to the attached image for more clarity:

Graphs a, b, and c all shows the number of cells against time (days).

Graph (a), P. aurelia is cultured

Graph (b), P. caudatum is cultured.

Graph (c), both species are cultured in one test tube.

In graph (c) we see logistic growth and a high cell density medium among the two species as P. aurelia blooms against P. caudatum which population reduces to zero.

Resource Partitioning is the solution to competitive exclusion. It employs a different resource and habitat, or feed to ward off competition.

not the best question format lol but what i think might as scale color is controlled by a single gene with two alleles, the green allele and the yellow allele. when moths that are homozygous for green scales are mated with moths that are homozygous for yellow scales, 100% of the offspring have green scales.