Ecology 6th Edition by Charles Krebs

Exercise 4

Population density (no. of individuals per m 2 ) of all organisms in all ecosystems falls with increasing body size, so that larger animals are less common. But for species of equal body size, aquatic organisms are 10-20 times more abundant in lakes than terrestrial organisms on land. Suggest two reasons why this might be. Cyr et al. (1997) discuss this issue.