SHEFFIELD, U.K. -- An international team of researchers, led by
the University of Sheffield, has demonstrated how Atlantic cod
responded to past natural climate extremes. The new research
could help in determining cods vulnerability to future global
warming. With fishing pressures high and stock size low, there
is already major concern over the current sustainability of cod
and other fisheries. The new findings, published in the journal,
Proceedings of the Royal Society B, show that natural climate
change has previously reduced the range of cod to around a fifth
of what it is today, but despite this, cod continued to populate
both sides of the North Atlantic. The researchers used a
computer model and DNA techniques to estimate where cod could be
found in the ice age, when colder temperatures and lower sea-
levels caused the extinction of some populations and the
isolation of others. The computer models used to estimate ice-
age habitats suitable for cod were developed by Professor Grant
Bigg, Head of the Univer