Inheritance of Acquired Characters a2) 
This view is prominently associated with the name of 
Lamarck, who held, however, a different view in regard 
to the origin of some of the other structures of the organism. 
Moreover, Erasmus Darwin, even before Lamarck, had sug- 
gested the principle of the inheritance of acquired characters. 
As has just been said, Lamarck held that the inheritance of 
acquired characters was only one of the ways in which ani- 
mals have become changed, and he clearly stated that in the 
case of all plants and of some of the lower animals the change 
(evolution) which he supposed them to undergo was due to 
the general influence of the environment. Since plants and 
the lower animals (as he supposed) have no central nervous 
system, or at least no such well-defined nervous system as 
have the higher animals, Lamarck thought that they could 
not have evolved in the same way as have the higher animals. 
We now know that, so far as the lower animals, at least, are 
concerned, there was no need for such a distinction, since 
many of their responses are like those of the higher animals. 
This distinction that Lamarck made is responsible, no doubt, 
for a misconception that was long held in regard to a part of 
his views. It is often stated that he supposed the desire 
of the animal for a particular part has led to the develop- 
ment of that part; while in reality he only maintained the 
desire to use a particular organ to fulfil some want led to 
its better development through exercise, and the result was 
inherited. Lamarck also supposed that the decrease in use 
of a part which leads to its decrease in size accounts for the ~ 
degeneration of organs. 
Lamarck first advanced his theory in 1801, when he cited 
the following examples in its favor. A bird, driven through 
want to the water to find its food, will separate its toes when 
they strike the water. The skin uniting the bases of the toes 
will be stretched in consequence, and in this way the broad 
membrane between the toes of ducks and geese has been 
acquired. The toes of a bird that is in the habit of perching 
