Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A tale of two seas: Last Ice Age has shaped sharks across Europe

13.11.2014

Shark populations in the Mediterranean are highly divided, an international team of scientists, led by Dr Andrew Griffiths of the University of Bristol, has shown.

Many previous studies on sharks suggest they move over large distances. But catsharks in the Mediterranean Sea appear to move and migrate much less, as revealed by this study. This could have important implications for conserving and managing sharks more widely, suggesting they may be more vulnerable to over-fishing than previously thought.


This depicts a catshark resting in the daytime.

Credit: David Sims


This is a catshark in the mirror.

Credit: David Sims

The study, published in the new journal Royal Society Open Science, used genetic techniques to investigate the population structure of the small-spotted shark, Scyliorhinus canicula. The species is common throughout Europe and has been eaten since ancient times, as documented in Roman mosaics.

In the UK anglers catch it for sport and it can often be seen in rock pools at low tide. The study found evidence of isolated populations in the Mediterranean, but no population division was found between catsharks around the North East Atlantic and British Isles.

During the last ice age, about 20,000 years ago, ice sheets occupied much of the Seas and Ocean of this region and catsharks probably didn't survive in the area. This means the region had to be recolonised, and there are very little genetic differences between them today.

The study also highlights differences in the movements of males and female catsharks - an increasingly common finding in sharks.

Dr Griffiths, based in the School of Biological Sciences, said: "It makes a lot of sense, females may want to stay in areas that are good for laying eggs, but males are often the dispersing sex, perhaps taking risks to increase how much they reproduce."

This research has conservation implications; if patterns of population structure vary hugely in different seas, and between the sexes, then shark resilience to fishing can vary greatly, meaning that better informed management could be needed for many species.

Paper

'A tale of two seas: contrasting patterns of population structure in the small-spotted catshark across Europe' by Gubili C et al in Royal Society Open Science.

Hannah Johnson | EurekAlert!

More articles from Earth Sciences:

nachricht Novel method for investigating pore geometry in rocks
18.06.2018 | Kyushu University, I2CNER

nachricht Decades of satellite monitoring reveal Antarctic ice loss
14.06.2018 | University of Maryland

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Novel method for investigating pore geometry in rocks

18.06.2018 | Earth Sciences

Diamond watch components

18.06.2018 | Process Engineering

New type of photosynthesis discovered

18.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>