Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Coralline algae in the Mediterranean lost their tropical element between 5 and 7 million years ago

08.07.2009
An international team of researchers has studied the coralline algae fossils that lived on the last coral reefs of the Mediterranean Sea between 7.24 and 5.3 million years ago. Mediterranean algae and coral reefs began to resemble present day reefs following the isolation of the Mediterranean from the Indian Ocean and global cooling 15 and 20 million years ago respectively.

The research team from the University of Granada (UGR) and the University of Modena and Reggio Emilia (Italia) show coralline algae distribution patterns in the west and centre of the Mediterranean Sea (in Salento, Italy and Almería, Spain) by way of a fossil register of 21 species collected in the two areas.

"Coralline algae are calcareous algae that are very common nowadays, although unknown to the general public, including naturalists, and quite often in fossil form, particularly in relatively modern rocks", Juan C. Braga, the chief author and a researcher at the Stratigraphy and Paleontology Department of the UGR explained to SINC.

The study, which was published recently in Palaeogeography Palaeoclimatology Palaeoecology, describes and interprets the disappearance of the last Messinian coral reefs (between 7.24 and 5.3 million years ago) in the Mediterranean Sea. "In subsequent, more recent eras, this sea has not had the right oceanographic conditions (above all a high enough temperature) to house coral reefs," Braga added.

When Tropical Coral Reefs Became Atlantic

During the period studied by the scientists through the coralline algae fossils found in the Mediterranean, the last few reefs boasted very little coralline diversity. "This is the result of the long history of global cooling over the last 20 million years and the isolation (separation) of the Mediterranean from the Indian Ocean, some 15 million years ago," the research says.

According to the results of the research, the relative abundance of coralline algae in reefs and slope deposits is 1-5% and 18% lower respectively in the Sorbas basin (Almería) than in Salento (Italy). Furthermore, the main components of the coralline algae assemblages found in shallow water are extant species that are very common in the Mediterranean.

Other species, such as Spongites fruticulosus and Phymatolithon calcareum, have lived in the western Mediterranean for more than 25 million years. However, the typical components of present-day coral reefs, such as Hydrolithon species with thick thalli, which were no longer present in the western region of the Mediterranean 7 million years ago.

"Just like reef corallines, algae flora reflects the cooling of the Mediterranean and its isolation from the Indian Ocean, and only a few tropical biotas existed in the Messinian era. Moreover, most of them already had Atlantic affinities and resembled the algae that still inhabits our coasts today", Braga states.

The Mediterranean-Atlantic characteristics of Messinian reef corallines therefore reflect the decrease in tropical biotas that occurred during the Miocene (around 20 million years ago). According to the research team, the widespread decline of this type of algae was due to global cooling and the isolation of the Mediterranean during the middle Miocene.

References:

Braga, Juan C.; Vescogni, Alessandro; Bosellini, Francesca R.; Aguirre, Julio. "Coralline algae (Corallinales, Rhodophyta) in western and central Mediterranean Messinian reefs" Palaeogeography Palaeoclimatology Palaeoecology 275(1-4): 113-128, 1 de mayo de 2009.

SINC | EurekAlert!
Further information:
http://www.plataformasinc.es

More articles from Ecology, The Environment and Conservation:

nachricht Scientists on the road to discovering impact of urban road dust
18.01.2018 | University of Alberta

nachricht Gran Chaco: Biodiversity at High Risk
17.01.2018 | Humboldt-Universität zu Berlin

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>