"On the subject of evolution, Austrailian scientists from the New England School recently discovered a case of human dwarfism on an island where elephants and other animals also experienced a loss of size. It seems that whenever animals live in a situation without competitors, they tend to reduce in size- a kind of inverse evolution. If size is a measure of progress: then removal of selection prosesses seems to promote regress."
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Thanks for the link to the news of the recently discovered Flores man. What struck me was the fact that members of this so-called "Hobbit" species were only about three feet tall and lived as recently as 18,000 years ago, which is contemporaneous with modern humans.
I tried to think of why an isolated population might have evolved this way. If we accept the Darwinian premise that random, heritable variations lead to differential reproductive success within a population (that is, that those variations within a gene pool which hinder survival tend to disappear whereas those variations which tend to aid survival tend to perpetuate), then from an adaptationist perspective we should be able to find some benefit to being so small.
It's known that as an object increases in size (while maintaining the same shape) it also suffers a decrease in relative surface area. For example, with a box (where length, width, height = y), the volume increases as the cube of y whereas the surface area only increases as the square of y.
So relative to modern humans, Flores man had a relatively larger surface area per unit body volume.
From biology we know that a greater relative surface area of lung alveoli is advantageous for respiration, that a greater relative surface area of skin is advantageous for perspiration (i.e. cooling), and a greater relative surface area of colon is advantageous for digestion. The smaller absolute volume means less oxygen and nutrients would be required to sustain life. In other words, being smaller is more physiologically efficient.
If the indigenous fauna were predatory, or if warfare was practiced, or if sexual selection were based on competition between males, then the advantages of strength as conferred by larger size might trump the physiological inefficiencies of largeness. However if these environmental conditions were absent, then any selective pressure for largeness would not exist.
These are just some thought that I came up with based on a basic understanding of science/ biology -- however I have no idea whether or not they're correct, or applicable to Flores man.
In any case, thanks again for the link!