Original post by candideI'm not so sure its that they've adapted to their environment, I think its that there is no selection pressure acting on them to keep them simple. e.g. when proto-whales entered the sea, they no longer had to worry about gravity, and retained (and indeed developed) their hugely complicated ungulate-like digestive system even tho for a krill-eating baleen whale this kind of complexity was un-necessary. But with bouyancy acting against the typical selective pressure of 'don't make it too heavy!', there was selection against heavy and useless winding digestive systems.
Similarly, say we have an ancestral language group of 5000 people, and twelve speakers dissappear into the darkest jungle to found a tribe. We could end up with a monoglot speaker population of 200 people, all speaking the same language, permanently isolated from the original population. Over hundreds of years, the jungle language evolves and gets way more complicated. One day someone invents a new gender, or tries out a new tense, or adds a new suffix for emphasis, and it catches on in the community. Because the only 200 people I know in the world speak this language, I'm obliged to speak the language, whatever frippery has been added - there is no pressure to keep it simple because no one from outside our jungle community speaks the language, we don't need to write it down, our children have all the time in the world to learn grammar rules... this happened with navajo, I think - a child wasn't fluent til they were 12, unlike English where we manage it by six.
So I suppose what I'm getting at is that in the 21st century there is tremendous pressure on speakers to keep English simple, standardized, easy to learn, but for my jungle language - used only by the community, associated intimately with their way of life - it can get as complicated as it likes and it will in no away affect its rate of proliferation cos no one was gonna learn it anyway!
Language is complex and beautiful and brilliant, but I think with 90% of the world pop speaking just 20 world languages, we're gonna see a decline in diversity and craziness. All the more reason to learn random languages like Anutan (or Gaidhlig for that matter!)