Adult neurogenesis appears to be a general phenomenon of mammals, being reported in a wide range of species. Although the majority of data on adult neurogenesis come from studies using rats and mice (Cameron & McKay, 1999; Snyder et al., 2009b), new granule cell production has been shown to occur in the dentate gyrus of dogs (Hwang et al., 2007; Cotman and Head, 2008), foxes (Amrein & Slomianka, 2010), tree shrews (Gould et al., 1997; Simon et al., 2005), marmosets (new world monkeys) (Gould et al., 1998; Leuner et al., 2007), macaques (old world monkeys) (Gould et al., 1999a; Perera et al., 2007; Kordower et al., 2010) and humans (Eriksson et al., 1998; Knoth et al., 2010). In fact, the only mammals investigated in which adult neurogenesis is either absent or occurs at a very low rate in the dentate gyrus are certain types of bats (Amrein et al., 2007). Taken together, these findings suggest that with rare exceptions, adult neurogenesis is a common feature of the mammalian dentate gyrus. The wide range of species in which adult neurogenesis occurs
