Which of the following processes describes the development of similar traits in unrelated species?

The development of similar traits in unrelated species is described by convergent evolution. This process occurs when different species, often in similar environmental conditions or ecological niches, evolve similar adaptations or traits independently. This can happen because they face similar challenges or selections that lead to analogous traits, such as wings in bats and birds or streamlined bodies in dolphins and sharks, which arise not from a common ancestor but as solutions to similar problems posed by their environments.

In contrast, the other processes listed involve different mechanisms of evolution. Parapatric speciation refers to the evolution of species that are geographically adjacent but develop reproductive barriers, while genetic drift is a random process that can result in changes in allele frequencies within a population over time, often affecting small populations. Allopatric speciation involves the formation of new species through geographic separation, leading to reproductive isolation. While these processes are fundamental concepts in evolutionary biology, they do not involve the independent development of similar traits among unrelated species, which is the essence of convergent evolution.