The main aim of the current Polarstern expedition to Antarctica is the investigation of marine ecosystems under the former Larsen ice shelf. This "white spot" with regard to biodiversity research gave rise to the following questions: What kind of life actually existed under the former floating ice shelf which was up to several hundreds of meters thick? What are the prospects for the future after the collapse of the ice shelf? Obviously, prosperous life did not exist in the area where the Larsen B ice shelf broke off three years ago. This is surprising since Antarctica's seafloor communities are known for their rich assemblages of sessile sponges, cnidarians and moss animals. Instead, underwater video footage and catches of towed sampling gear revealed the dominance of typical deep-sea animals and corresponding life forms.
Here, sea cucumbers and stalked feather stars are the main representatives. These deep-sea inhabitants belong to a group called echinoderms. Until now, stalked feather stars have only been found sporadically and then only below 800m water depths in this sector of Antarctica. But locally in the Larsen B region, they occurred rather frequently at depths of merely 200m. "During my nine expeditions to Antarctica, the only time I have seen the two most abundant species of sea cucumbers was below the far bigger Filchner-Ronne ice shelf further south." This second encounter brought back chief scientist Julian Gutt's memories of his first trip to Antarctica and his PhD thesis 21 years ago. Preliminary results show that a unique macrofauna exists in conjunction with the ice shelf. The sea cucumber Elpidia is probably the most prominent deep-sea animal but is also known to occur in shallow Arctic waters. Maybe this is the reason why this animal is aptly named glacialis (icy) especially with regard to our confirmatory findings on the opposite pole – Antarctica.
This species, its bigger "sister" Scotoplanes globosa and other relatives according to their feeding mode are referred to as grazers. Myriads of single-celled algae that sink down to the seafloor are literally grazed by herds of sea cucumbers. The oceanographer Enrique Isla is excited about further processing the collected data back in the Marine Sciences Institute (ICM) in Barcelona. "Our measurements of environmental parameters of the sediment and the water column will contribute to answer the question, why there are such similarities between habitat use of the deep-sea and below the former ice shelf." Scientists on this expedition will meet again in autumn in Barcelona to work on a synthesis of various results combining the different aspects of ecosystem components. This workshop will be hosted by the ICM and is supported by the Census of Antarctic Marine Life (CAML). Marine ecologist Julian Gutt is looking to the future: "The minute we have a better understanding of how ecosystems under the ice shelf work we might dare to put forward prognoses how biodiversity on the seafloor changes with respect to ongoing atmospheric warming".
Dr. Angelika Dummermuth | EurekAlert!
Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg
Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Life Sciences
23.02.2018 | Earth Sciences
23.02.2018 | Materials Sciences