摘要
Transition from a nocturnal to a diurnal lifestyle represents a major shift in primate evolution, plays a central role in the adaptation of these species to new habitats, and is involved in modifications to their physiological and social behaviors （Heesy and Ross, 2001; Shultz et al., 2011）. However, two core problems concerning the circadian rhythm transition re- mains unresolved. First, there is controversy concerning the activity pattern of the ancestral primate （Heesy and Ross, 2001; Tan et al., 2005）. Second, the transition process for circadian rhythm in primate evolutionary history is unre- solved. Although most research suggests that primates trans- formed from a nocturnal to a diurnal circadian rhythm in the lineage leading to the common ancestor of the anthropoids or the haplorrhines （anthropoids and tarsier） （Ross, 2000; Heesy and Ross, 2001）, evidence has been insufficient to determine whether this occurred in the lineage leading to the common ancestor of the haplorrhines or the anthroooids.
Transition from a nocturnal to a diurnal lifestyle represents a major shift in primate evolution, plays a central role in the adaptation of these species to new habitats, and is involved in modifications to their physiological and social behaviors （Heesy and Ross, 2001; Shultz et al., 2011）. However, two core problems concerning the circadian rhythm transition re- mains unresolved. First, there is controversy concerning the activity pattern of the ancestral primate （Heesy and Ross, 2001; Tan et al., 2005）. Second, the transition process for circadian rhythm in primate evolutionary history is unre- solved. Although most research suggests that primates trans- formed from a nocturnal to a diurnal circadian rhythm in the lineage leading to the common ancestor of the anthropoids or the haplorrhines （anthropoids and tarsier） （Ross, 2000; Heesy and Ross, 2001）, evidence has been insufficient to determine whether this occurred in the lineage leading to the common ancestor of the haplorrhines or the anthroooids.
基金
supported by the grants from the National Natural Science Foundation of China(Nos.2007CB411600 and 2008GA001)
the Bureau of Science and Technology of Yunnan Province(No.31061160189)
supported by the West Light Foundation of the Chinese Academy of Sciences
