Marine biologist Dr. Tanaka claims that the decline of kelp forests along the California coast is primarily caused by an explosion in the population of purple sea urchins, which graze on kelp.
Which finding, if true, would most strongly support Dr. Tanaka's claim?
- A
Some species of kelp grow faster in warmer temperatures.
- B
Kelp forests have declined in regions where sea otter populations have grown.
- C
Purple sea urchins can survive in low-oxygen water for several days.
- Dcheck_circle
Areas with the steepest kelp loss show purple sea urchin densities ten times higher than historical averages.
Explanation
Choice B directly links the regions of greatest kelp loss to the highest urchin densities, supporting causation. A actually contradicts (otters eat urchins). C and D are tangential.