Whilst evolutionists generally accept the Malthusian (constant rate exponential) nature of population growth, others such as Dawkins (1996) sometimes point out that an exponential growth model (for example, when applied to local doubling of cell populations) is naive. However, even Dawkins (1996) does not always qualify his (typically Malthusian) explanation of exponential growth: Demographer Joel E. Cohen (1995) is highly critical of such views, arguing that: "...Population growth was not exponential during these millennia, whatever Malthus and others may have thought."