Here is a portion of (and link to) an interesting article on earthworms, their initially human induced spread around the world, and how different species are currently competing and adapting to foreign lands. If the history of human colonization had been focused a bit more on the proper utilization of waste biomass the world might be a better place today…
(From the BBC)
Earthworms are generally considered to be good news. As highly effective composters, they are often referred to as the “best friend” of gardeners and farmers.
Earthworms break down and recycle decaying plant matter, and loosen, mix and fertilise soil by bringing nutrients closer to the surface. But their efficiency is not always so welcome.
There is a global earthworm invasion taking place. Alien species of the slow-moving, innocuous-looking creatures have conquered almost every continent.
They are out-competing native wildlife, adapting to deforested and cultivated soils more effectively than native species, and changing soil structure.
The race is now on to understand how they are doing it and, more importantly, what damage they may be causing.
Read full article on BBC: Earthworm Invasion