Evolution of Cichlids in Lake Tanganyika: A Case of Speciation

What process has occurred among cichlids in Lake Tanganyika?

a. Genetic drift
b. Mass extinction
c. Allopatric speciation
d. Sympatric speciation
Final answer:

The process that has occurred among cichlids in Lake Tanganyika is both allopatric and sympatric speciation.

Explanation:

In Lake Tanganyika, many species of cichlids have evolved from a common ancestor through the process of speciation. Speciation refers to the formation of new species from a pre-existing population. In the case of Lake Tanganyika cichlids, two types of speciation have occurred: allopatric speciation and sympatric speciation.

Allopatric speciation occurs when a population becomes geographically isolated, leading to reproductive isolation and the formation of new species. This can happen when a physical barrier, such as a mountain range or a body of water, separates a population. In the case of Lake Tanganyika cichlids, geographic isolation within the lake itself has led to the formation of new species.

Sympatric speciation, on the other hand, occurs within the same geographic area without any physical barriers. This process can be driven by factors such as ecological niche differentiation, sexual selection, or genetic mutations. In Lake Tanganyika, sympatric speciation has also played a role in the evolution of cichlids. Different cichlid species have adapted to different ecological niches within the lake, leading to the development of distinct species.

These processes of allopatric and sympatric speciation have led to the diverse array of cichlid species found in Lake Tanganyika today. The unique environmental conditions and evolutionary pressures within the lake have contributed to the evolution and adaptation of cichlids over time.