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 University of Sheffield’s Department of Geography. These climatic analyses were combined with genetic studies by US researchers at Duke University and the University of California, and ecological information prepared by colleagues at the University of East Anglia and the Institute of Marine Research in Norway.
On land, plants and animals (including humans) are known to have moved further south when the northern ice sheets reached their maximum extent around 20,000 years ago. Similar migrations must have happened for plankton and fish in the sea. But there were two added complications: firstly, greatly reduced sea levels meant that many shallow and highly productive marine habitats around Europe and North America ceased to exist. Secondly, the ice-age circulation patterns in the North Atlantic caused the temperature change between tropical and polar conditions to occur over a much shorter north-south distance, reducing the area suitable for temperate species – such as cod.
The new analyses included these effects, together with other environmental and ecological information, in order to estimate where it was possible for Atlantic cod to reproduce and survive.
The results indicated that the ice-age range of Atlantic cod extended as far south as northern Spain, but the total area of suitable habitat was much more restricted. Nevertheless, populations of cod continued to exist on both sides of the North Atlantic. These findings were confirmed by genetic data, based on over a thousand DNA analyses of present-day cod populations, from Canada, Greenland, Iceland and around Europe.
Professor Bigg said: “This research shows that cod populations have been able to survive in periods of extreme climatic change, demonstrating a considerable resilience. However this does not necessarily mean that cod will show the same resilience to the effects of future climatic changes due to global warming.”
UCI and NASA document accelerated glacier melting in West Antarctica
26.10.2016 | University of California - Irvine
Ice shelf vibrations cause unusual waves in Antarctic atmosphere
25.10.2016 | American Geophysical Union
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
27.10.2016 | Life Sciences
27.10.2016 | Life Sciences
26.10.2016 | Power and Electrical Engineering