Life's little builders

Niche construction and evolution

source: Kevin Laland and John Odling-Smee
New Scientist no 2421, November 15 2003
starts p42, 4 pages long

Living creatures are able to alter their environments, as well as being affected by their environments. Conventional views tend to focus on the way that natural selection adapts species to environments, but niche construction is important, and goes beyond beavers making dams, and the like. Niche construction is worthy of study, due to its importance in evolution. Eartworms are a good illustration of niche construction and its importance. They have altered soil chemistry and construction through mixing plant and inorganic material, and producing worm casts. Cumulative change means that modern earthworms inhabits environments that their ancestors altered. Niche construction means that earthworms shape the pressures of natural selection. Ecosystems can be understood as super-constructions that constituent organisms have created. Sometimes species pull in opposite directions, since species' activitities are not always coordinated.

Understanding niche construction can help with conservation. It can help understand how humans affect ecosystems, and how ecosystems can be preserved through preserving the impact of niche construction, rather than species that construct niches.