Figure 14.1 Lizard predation on spiders. (a) In the Bahamas, researchers introduced a total of 20 spiders to each of five small islands with predatory lizards and to five small islands without lizards. (b) Spiders were introduced to each island on two dates, indicated by the red arrows. The spiders remained rare or absent on islands with lizards but increased 10-fold on islands without lizards. Error bars are standard errors.

Data from T. W. Schoener and D. A. Spiller, Effect of predators and area on invasion: An experiment with island spiders, Science 267 (1995): 1811–1813. Photo by Jason J. Kolbe.