Figure 42.4: Resource Acquisition Increases with Resource Availability—Up to a Point (A) A plant’s photosynthetic rate increases with light intensity. (B) Kangaroo rats (Dipodomys spp.) are able to harvest seeds faster as seed density increases. (Note the cheek pouch bulging with seeds.) Error bars indicate 95 percent confidence intervals around the mean. See Appendix B for discussion of statistical concepts.