Environmental science is not a journalistic specialty of mine, so I'll tread into this terrain gingerly, and leave the heavy lifting to Carl Zimmer in the discussion of a paper that came out today in Science about the loss of butterfiles, birds and plants in Britain over the last 20 to 40 years.
The science, in a nutshell:
There is growing concern about increased population, regional, and global extinctions of species. A key question is whether extinction rates for one group of organisms are representative of other taxa. We present a comparison at the national scale of population and regional extinctions of birds, butterflies, and vascular plants from Britain in recent decades. Butterflies experienced the greatest net losses, disappearing on average from 13% of their previously occupied 10-kilometer squares. If insects elsewhere in the world are similarly sensitive, the known global extinction rates of vertebrate and plant species have an unrecorded parallel among the invertebrates, strengthening the hypothesis that the natural world is experiencing the sixth major extinction event in its history.
If insects elsewhere are similarly sensitive, we tentatively agree with the suggestion that the known global extinction rates of vertebrate and plant species may have an unrecorded parallel among the insects, strengthening the hypothesis derived from plant, vertebrate, and certain mollusk declines, that the biological world is approaching the sixth major extinction event in its history.