Page 154 - The Miracle in the Immune System

152 THE MIRACLE OF THE IMMUNE SYSTEM

Lamarck's Impact

So, how could these
"favourable variations" occur?
Darwin tried to answer this
question from the standpoint
of the primitive understand-
ing of science at that time.
According to the French biol-
ogist Chevalier de Lamarck
(1744-1829), who lived
before Darwin, living crea-
tures passed on the traits
French biologist Lamarck
they acquired during their
lifetime to the next generation. He asserted that these
traits, which accumulated from one generation to
another, caused new species to be formed. For
instance, he claimed that giraffes evolved from
antelopes; as they struggled to eat the leaves of high
trees, their necks were extended from generation to
generation.
Darwin also gave similar examples. In his book The
Origin of Species, for instance, he said that some bears
going into water to find food transformed themselves
into whales over time. 26
However, the laws of inheritance discovered by
Gregor Mendel (1822-84) and verified by the science of
genetics, which flourished in the twentieth century,
utterly demolished the legend that acquired traits were
passed on to subsequent generations. Thus, natural
selection fell out of favour as an evolutionary mecha-
nism.