The Sparseness Adaptation
theory of autism shows that some autism is the result of
adaptation to the sparseness of population frontiers.
The theory is about how autism came to be.
It points out that lack of social ability is the main
feature of autism. The theory shows that autism is not always a disease
and that some forms of autism exist for a simple reason:
Every population has a surrounding frontier where there are few members.
Adaptation to frontier sparseness produces a Sparseness Adaptation Syndrome
that plausibly accounts for much of autism. In other words
autism is an expected
result of adaptation to the unrelenting sparseness of population frontiers.
Because every population always has a surface, autism is a natural and
major feature of brain evolution. The theory expects autism to have a
range of severities and many varieties. These prevent tidy diagnosis of
autism. The Sparseness Adaptation theory of autism does not strictly depend on
Darwin's theory of evolution, and unlike Darwin's theory it makes
predictions. For example, it predicts a correlation of autism and
global position of ancestral homeland. The theory also explains why autism
occurs more often in males than in females.