8 
The Queensland Naturalist. 
VoL. 2 
TRANSACTIONS. 
MODERN EVOLUTIONARY THOUGHT. 
By Heher H. Longman. 
Presidential Address, January, 1914. 
At one time the process of evolution was looked upon 
as comparatively simple. It was asserted that the law of life 
was a demonstration of definite, regular, and unbroken progress 
ranging from simple, unicellular, primitive forms to complex, 
specialised, inter-associated and inter-dependent organisms, 
of which man and the higher animals are culminating points. 
Perhaps this can be best instanced by taking a work such 
as Drummond’s '‘Ascent of Man.” There it is stated that 
evolution is the study of “Nature in the vertical plane,” 
showing continuous progress from low to high, an ascent 
which the forces of altruism triumphing over the powers 
of egotism, that “ the same great patient unobtrusive law 
has guided and shaped the whole from its beginnings in be- 
wilderment and chaos to its end in order, harmony, and 
beauty.” This grandly simple view was at once grasped 
by popular imagination ; it was seized upon by preachers 
as but an elaboration of the account of the creation in Genesis ; 
it was the basic conception of popular science articles, and 
was epitomised by poets. There was also a tendency to 
make simple and dogmatic assertions as to the factors or 
dynamic forces of evolution, and both theological and anti- 
theological writers tabulated the facts of nature to suit their 
repective purposes. 
But now we find it is necessary to qualify and amplify 
the old standpoints— not so much that they were inaccurate 
but rather because they were inadequate. Evolution itself 
is so demonstrably true, and is supported on so many grounds, 
that it scarcely seems worth while contradicting the few 
faddists who oppose it. But we are now concerned with 
problems as to the method and the meaning of evolution, 
and here the keenest thinkers are prepared to extend rather 
than to narrow their views, and to recognise varying influences 
instead of insisting on one sole princijde. 
Many factors have assisted to bring about this wider 
view of evolution. Since the genius of the great Darwin 
caused scientific workers “ to think in terms of evolution,” 
a powerful incentive has been operating. It is the glory of 
science that she knows no orthodoxy, and sets up no sacred 
system of authority. The work of all investigators is subject 
