Two species of lizards, the canyon lizard, Sceloporus merriarni, and the tree lizard, Urosaurus ornatus both hunt for insect prey on rock surfaces. In 1976, an experimenter established removal plots, where one species of lizard was removed. Here are the resultant densities of lizards: Urosaurus with Sceloporus 55, Urosaurus alone 80, Sceloporus with Urosaurus 130, Sceloporus alone 129. What can you conclude?

Question

Quizplus · Accepted Answer

The data shows that the density of Sceloporus does not significantly change whether Urosaurus is present or not (130 vs. 129), indicating Sceloporus is not affected by the presence of Urosaurus, suggesting it is a better competitor. In contrast, the density of Urosaurus increases significantly when Sceloporus is removed (from 55 to 80), indicating it was being suppressed by the presence of Sceloporus, further supporting that Sceloporus is a better competitor.

Two Species of Lizards, the Canyon Lizard, Sceloporus Merriarni, and the Tree