CHAPTER VI 
THE EVOLUTION OF MAN: PALAEONTOLOGY: 
RicHARD Swann LULL 
ORIGIN OF PRIMATES 
Stock.—There is but little doubt that two important orders of 
modern mammals, the. Carnivora and the Primates, had a common 
origin, diverging mainly along lines determined by a dietary contrast, 
as the former have become more strictly flesh-eating or predaceous, 
the latter largely fruit-eating and as a consequence more completely 
arboreal. Back of each group lie as annectant forms the Insectivora, 
not perhaps such as are alive to-day, as all these are highly specialized 
along diverse lines, but generalized insectivores possessing, because 
of their primitiveness, a wider range of potential adaptation. Mat- 
thew is ‘‘disposed to think of these, our distant ancestors, at the dawn 
of the Tertiary, as a sort of hybrid between a lemur and a mongoose, 
rather catholic in their tastes, living among and partly in the trees, 
with sharp nose, bright eyes, and a shrewd little brain behind them, 
looking out, if you will, from a perch among the branches, upon a 
world that was to be singularly kind to them and their descendants.”’ 
Thus we can define the stock as a relatively large-brained arboreal 
insectivore, of primitive but adaptable dentition, and especially of 
progressive mentality. 
Time.—The time of primate origin must have been not later 
than basal Eocene, as primates, clearly definable as such, are found in 
the Lower Eocene rocks of both Europe and North America. 
Place.—The simultaneous appearance of the primate in the 
Old World and the New gives rise to the same conclusions as to their 
place of origin and their migrations thence as with other modernized 
mammals. It suffices now to say that their ancestral home was 
boreal Holarctica, probably within the limits of the present continent 
of Asia, whence they migrated southward along the three great 
continental radii. “The impelling cause of this migration was the 
increasing northern cold, before which the boreal limitations of the 
tropical forests retreated, carrying with them the primates which, in 
tFrom R. S. Lull, Organic Evolution (copyright 1917). Used by special 
permission of the publishers, The Macmillan Company. 
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