New research shows that the loss of
biodiversity can increase the risk of "extinction cascades", where an
initial species loss leads to a domino effect of further extinctions.
The researchers, from the University of
Exeter, showed there is a higher risk of extinction cascades when other species are not present to fill the "gap" created by the
loss of a species.
Even if the loss of one species does not
directly cause knock-on extinctions, the study shows that this leads to simpler
ecological communities that are at greater risk of "run-away extinction
cascades" with the potential loss of many species.
With extinction rates at
their highest levels ever and numerous species under threat due to human
activity, the findings are a further warning about the consequences of eroding
biodiversity.
"Interactions between species are
important for ecosystem (a community of interacting species) stability,"
said Dr Dirk Sanders, of the Centre for Ecology and Conservation at the
University of Exeter's Penryn Campus in Cornwall. "And because species are
interconnected through multiple interactions, an impact on one species can
affect others as well.
"It has been predicted that more complex
food webs will be less vulnerable to extinction cascades because there is a
greater chance that other species can step in and buffer against the effects of
species loss.
"In our experiment, we used communities
of plants and insects to test this prediction."
The researchers removed one species of wasp
and found that it led to secondary extinctions of other, indirectly linked,
species at the same level of the food web.
This effect was much stronger in simple
communities than for the same species within a more complex food web.
Posts
No comments:
Post a Comment
You only need to enter your comment once! Comments will appear once they have been moderated. This is so as to stop the would-be comedian who has been spamming the comments here with inane and often offensive remarks. You know who you are!