Abstract
Zeng et al. (1990, henceforth denoted ZPE) found chaotic behavior in daisyworld (Watson and Lovelock, 1983, henceforth denoted WL), a simple nonlinear model of an idealized world containing only species of daisies of various albedos. The planetary albedo depends on the coverage of each type of daisy, and the daisies have temperature-dependent growth rates, enabling feedback between the environment (temperature) and the biota (daisies).