Final answer:
The introduction of the Nile perch to Lake Victoria led to the extinction of around 200 cichlid species, significantly reducing biodiversity and altering the ecosystem. Factors such as poor water quality and overfishing contributed to this decline, highlighting a complex interaction involving human activity and introduced species.
Step-by-step explanation:
The introduction of Nile perch into Lake Victoria has been a subject of much debate. This large predatory fish was introduced to boost fisheries and feed local populations around the 1960s, but the exponential growth in their number in the 1980s led to catastrophic declines in cichlid species, contributing to the extinction of approximately 200 cichlid species. This biodiversity loss in Lake Victoria also resulted from declining water quality due to agriculture and land clearing, and increased fishing pressure. The Nile perch consumed vast numbers of cichlids, reducing the diversity of the ecosystem that biologists had not even fully catalogued, leading to the irreparable loss of potentially new species.