Lake Victoria and the Amazing Cichlids
How did the introduction of the Nile perch affect the cichlid population in Lake Victoria?
A. Increased gill surface area has allowed the cichlids to change their diet and avoid competing with the Nile perch.
B. Increased gill surface area has allowed the cichlids to be camouflaged and avoid being eaten by the Nile perch.
C. Increased gill surface area has allowed the cichlids to leave Lake Victoria and establish populations in nearby bodies of water.
D. Increased gill surface area has allowed the cichlids to better absorb the limited oxygen in the water.
Answer:
D. Increased gill surface area has allowed the cichlids to better absorb the limited oxygen in the water.
The introduction of the predatory Nile perch in Lake Victoria had a significant impact on the cichlid population. As the Nile perch became the dominant fish species in the lake, the number of cichlid species decreased. The Nile perch preyed heavily on cichlid species that fed on algae and debris at the bottom of the lake. This led to an increase in algae growth and a decrease in oxygen levels in the lake.
With the decrease in oxygen levels, the cichlids had to adapt to survive in the changing environment. One of the ways they adapted was by increasing their gill surface area. This allowed them to better absorb the limited oxygen in the water and improve their chances of survival.
By evolving to have larger gills, the cichlids were able to overcome the challenges posed by the Nile perch and the changing conditions in Lake Victoria. This adaptation helped them thrive in the face of adversity and continue their existence in the lake.