A new study of animal populations
shows that even widely separated populations of a single species
will go extinct together if a common external force is applied.
Take the analogy of two grandfather clocks falling into synchrony
through subtle vibrations in the floorboards linking the two
clocks. In the same way a common stimulant, in the form, say, of
predators or adverse climate conditions, can synchronize the fate of
separate enclaves of an endangered species.
R.E. Amritkar of the
Physical Research Laboratory, in Ahmedabad, India, and Govindan Rangarajan of
the Indian Institute of Science, in Bangalore, began with actual field
data that had demonstrated the synchronizing influence of predators
populations and then applied principles from nonlinear dynamics to
simulate future behavior. They conclude that provided there is a
common threat, separated communities of the species will synchronize
together before becoming extinct.
This is bad news for
conservationists hoping that some decimated species could survive in
isolation. They show that the net resistance to extinction can be
expressed as a parameter which puts the degree of endangeredness
into numerical form.
This theory can help explain why species got
decimated on a global scale in previous mass extinction events.
Physical Review Letters, upcoming article
Contact Govindan Rangarajan, email@example.com, 91-80-23600373
Govindan Rangarajan's Web site