Friday, 29 May 2015

Erasmus Darwin (1818) on selection (sexual and natural)

[For information on further anticipators visit: Natural Selection before Darwin and Wallace.] 

Erasmus Darwin (1818. Zoonomia, vol. I, p. 396):

"The birds, which do not carry food to their young, and do not
therefore marry, are armed with spurs for the purpose of fighting
for the exclusive possession of the females, as cocks and quails.
It is certain that these weapons are not provided for their defence
against other adversaries, because the females of these species arc
without this armour. The final cause of this contest amongst the
males seems to be, that the strongest and most active animal should
propagate the species, which should thence become improved
       Another, great want consists in the means of procuring food,
which has diversified the forms of all species of animals. Thus
the nose of the swine has become hard for the purpose of turning
up the soil in search of insects and of roots. The trunk of the
elephant is an elongation of the nose for the purpose of pulling
down the branches of trees for his food, and for taking up water
without bending his knees. Beasts of prey have acquired strong
jaws or talons. Cattle have acquired a rough tongue and a
rough palate to pull off the blades of grass, as cows and sheep.
Some birds have acquired harder beaks to crack nuts, as the par-
rot. Others have acquired beaks adapted to break the harder
seeds, as sparrows. Others for the softer seeds of flowers, or the
buds of trees, as the finches. Other birds have acquired long
beaks to penetrate the moister soils in search of insects or roots,
as woodcocks; and others broad ones to filtrate the water of lakes,
and to retain aquatic insects, as ducks. All which seem to have
been gradually produced during many generations by the perpetual
endeavour of the creatures to supply the want of food, and to have
been delivered to their posterity with constant improvement of
them for the purposes required."