Analyze the food web shown here. A researcher claims that the sea stars are acting as a keystone species in the area. To test this claim, the researcher removes the sea stars from a community and measures the changes in biodiversity. Which results would support the claim that the sea stars are a keystone species in the area? Select ALL that apply.

Question

Responses
A Mussels become very abundant without sea stars.Mussels become very abundant without sea stars.
B An increase in benthic algae occurs without the presence of the starfish.An increase in benthic algae occurs without the presence of the starfish.
C Fewer producers at the bottom of the food chain are present due to overgrazing.Fewer producers at the bottom of the food chain are present due to overgrazing.
D A reduction in the mussel population occurs due to being consumed by larger predators.A reduction in the mussel population occurs due to being consumed by larger predators.
E A reduction of the species number of barnacles that can be supported by the community occurs.

Answer 1

A, B, and E.

A decrease in mussel abundance and an increase in benthic algae without the presence of sea stars would support the idea that sea stars are a keystone species. Additionally, a reduction in the species number of barnacles that can be supported by the community without sea stars would also indicate the importance of sea stars in maintaining biodiversity in the area.