PRESIDENTIAL ADDRESS. 589 
choice, found immediate expression in a bewildering variety of specialisations of 
structure adapted to different modes of life. Some mammals became fleet of 
foot, and developed limbs specially adapted to enhance their powers of rapid 
movement. They attained an early pre-eminence, and were able to grow to 
large dimensions in the slow-moving world at the dawn of the age of mammals. 
Others developed limbs specially adapted for swift attack and habits of stealth, 
successfully to prey upon their defenceless relatives. Others took to the water 
or the air, and acquired the modifications in structure and manners of life 
necessary to accommodate themselves to their new environments. 
Most of these groups attained the immediate success that often follows upon 
early specialisation: but they also paid the inevitable penalty. They became 
definitely committed to one particular kind of life; and in so doing they had 
sacrificed their primitive simplicity and plasticity of structure, and in great 
measure their adaptability to new conditions. The retention of primitive 
characters, which so many writers upon biological subjects, and especially upon 
anthropology, assume to be a sign of degradation, is not really an indication of 
lowliness. We should rather look upon specialisation of limbs and the narrowing 
of the manner of living to one particular groove as confessions of weakness, the 
renunciation of the wider life for one that is sharply circumscribed. It may be 
asked why all these other non-Primate mammals, leading an active life, many of 
them in open competition with their fellows, did not develop brains as highly 
organised as those of the Primates. The Ungulates and Carnivores, which most 
people who put such queries have in mind when they do so, develop large brains, 
although they are relatively very small in comparison with those of Primates of 
similar size. There are many reasons for this. Such creatures, even at the 
present day, always remain more or less under the influence of the sense of smell ; 
and even though the visual, auditory, and tactile senses become well represented 
in the neopallium, these are secondary and relatively late modifications which 
have produced much less effect than the earlier usurpation of the dominant 
position by vision exerted in the Primates. Nevertheless, visual and auditory 
centres and the interposed parietal area become well developed, especially in 
Carnivora like the Dog, Cat, Bear, and Seal—an anatomical fact which explains 
their high degree of educability. But the growth of other cortical areas is 
subject to inevitable limitations in these creatures. The specialisation of limbs, 
and this is peculiarly the case in Ungulates, to perform only a very limited 
range of more or less automatic movements, does away with all possibility of 
developing further either an area to preside over skilled movements or a control- 
ling prefrontal ‘area of attention,’ the usefulness of which is restricted by the 
impossibility of performing many acts that call for such guidance. Further 
progress along these lines was barred for all time by early specialisation of 
structure of the limbs; and hence these creatures lack one of the chief means 
which has led the Primate to the position of mental supremacy. 
The Primates at first were a small and humble folk, who led a quite 
unobtrusive and safe life in the branches of trees, taking small part in the fierce 
competition for size and supremacy that was being waged upon the earth 
beneath them by their Carnivorous, Ungulate, and other brethren. But all the 
time they were cultivating that equable development of all their senses and 
limbs, and that special development of the more intellectually useful faculties of 
the mind which, in the long run, were to make them the progenitors of the 
dominant mammal—the mammal who was to obtain the supremacy over all others, 
while still retaining much of the primitive structure of limb that his competitors 
had sacrificed. It is important, then, to keep in mind that the retention of 
primitive characters is often to be looked upon as a token that their possessor 
has not been compelled to turn aside from the straight path and adopt protec- 
tive specialisations, but has been able to preserve some of his primitiveness and 
the plasticity associated with it, precisely because he has not succumbed or 
fallen away in the struggle for supremacy. It is the wider triumph of the 
individual who specialises late, after benefiting by the all-round of experience of 
early life, over him who in youth becomes tied to one narrow calling. 
The Primates found in the branches of trees the asylum and protection neces- 
sary for the cultivation of brain and limbs during the period of their obscurity 
as an insignificant tribe; but when they became powerful enough to hold their own 
and wax great, both in size and power, they had maintained sufficient of their 
