Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


An international team including scientists from MARUM discovered ongoing and future tropical diversity decline


How can patterns in the marine biodiversity of the past help us to understand how it may change in the future? A study published today by an international team including Prof. Michal Kucera and Dr. Kerstin Kretschmer from MARUM – Center for Marine Environmental Sciences at the University of Bremen finds that the tropical diversity decline now seen in the ocean is not purely human induced, but nonetheless will worsen considerably if we do not limit anthropogenic climate warming.

The research, published in Proceedings of the National Academy of Sciences (PNAS), used fossils to reconstruct global oceanic biodiversity patterns for the last ice age (approximately 20,000 years ago) and the pre-industrial period, i.e. before 1950, and used the results to make projections for the near future (2090s).

Shells of plank­tonic fo­raminifera from ice-age sed­i­ments in the At­lantic Ocean. Fossils like these were used in this study to re­veal that global warm­ing may lead to de­cline in trop­ical mar­ine biod­iversity.

(Photo: MARUM – Cen­ter for Mar­ine En­vir­on­mental Sci­ences at the Uni­versity of Bre­men)

The equatorial "dip" in diversity that is observed today existed already during the pre-industrial period but it was not present during the last ice age. The decline of tropical diversity is the result of warming after the ice age, and it appears that anthropogenic warming will worsen the tropical diversity decline further.

By the end of the 21st century, tropical diversity may decrease to levels not seen for millions of years if our future aligns with the "business-as-usual" CO2 emission scenario.

The pelagic ocean covers the vast majority of Earth’s surface and is the largest biome on Earth. It is home to phytoplankton that play a key role in global oxygen production, top predators and economically important species that are increasingly under threat from climate change.

To reconstruct the past state of tropical marine diversity, the researchers used tiny shells of fossil plankton called foraminifera. These shells are preserved in marine sediments and act as sentinels of changes in past pelagic ecosystems.

“Biodiversity is usually high in the tropics and low at the poles. We call this important pattern the ‘latitudinal diversity gradient’. Yet, recent studies have found that global marine biodiversity patterns often show an equatorial 'dip' of diversity. We wanted to explore what caused this, and whether it was a recent pattern,” says lead author Moriaki Yasuhara from the University of Hong Kong (China).

"These clear links between warming and reduced tropical biodiversity mean that by the end of this century oceanic diversity at the equator may dip to a level unprecedented in human history,” co-author Derek P. Tittensor, associate professor at Dalhousie University, concluded.

“This research shows furthermore how data on past marine ecosystems preserved in marine sediments provide scenarios of diversity change relevant to the assessment of global change policies,” adds co-author Michal Kucera from MARUM.

Wissenschaftliche Ansprechpartner:

Prof Michal Kucera
MARUM working group Micropaleontology – Paleoceanography
Phone: +49 421 21865970


Moriaki Yasuhara, Chih-Lin Wei, Michal Kucera, Mark J. Costello, Derek P. Tittensor, Wolfgang Kiessling, Timothy C. Bonebrake, Clay Tabor, Ran Feng, Andrés Baselga, Kerstin Kretschmer, Buntarou Kusumoto, and Yasuhiro Kubota (2020): Past and future decline of tropical pelagic biodiversity. Proceedings of the National Academy of Sciences of the United States of America. DOI: 10.1073/pnas.1916923117

Weitere Informationen:

Jana Nitsch | idw - Informationsdienst Wissenschaft

More articles from Earth Sciences:

nachricht Satellite data show severity of drought summers in 2018 and 2019
13.07.2020 | GFZ GeoForschungsZentrum Potsdam, Helmholtz Centre

nachricht NASA analyzes Tropical Cyclone Cristina's water vapor concentration
09.07.2020 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron cryo-microscopy: Using inexpensive technology to produce high-resolution images

Biochemists at Martin Luther University Halle-Wittenberg (MLU) have used a standard electron cryo-microscope to achieve surprisingly good images that are on par with those taken by far more sophisticated equipment. They have succeeded in determining the structure of ferritin almost at the atomic level. Their results were published in the journal "PLOS ONE".

Electron cryo-microscopy has become increasingly important in recent years, especially in shedding light on protein structures. The developers of the new...

Im Focus: The spin state story: Observation of the quantum spin liquid state in novel material

New insight into the spin behavior in an exotic state of matter puts us closer to next-generation spintronic devices

Aside from the deep understanding of the natural world that quantum physics theory offers, scientists worldwide are working tirelessly to bring forth a...

Im Focus: Excitation of robust materials

Kiel physics team observed extremely fast electronic changes in real time in a special material class

In physics, they are currently the subject of intensive research; in electronics, they could enable completely new functions. So-called topological materials...

Im Focus: Electrons in the fast lane

Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.

Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....

Im Focus: The lightest electromagnetic shielding material in the world

Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.

Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

International conference QuApps shows status quo of quantum technology

02.07.2020 | Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Latest News

Shedding light on the brown color of algae

14.07.2020 | Life Sciences

Color barcode becomes ISO standard

14.07.2020 | Information Technology

New substance library to accelerate the search for active compounds

14.07.2020 | Life Sciences

Science & Research
Overview of more VideoLinks >>>