Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


It’s complicated - new insights into the evolutionary history of bears


According to researchers of the LOEWE Biodiversity and Climate Research Centre (BiK-F), Goethe University Frankfurt and the U.S. Wildlife Service several bear species that today only occur in America or in Asia have hybridized in their evolutionary history. The Beringia land bridge, which in former times connected the habitats of these species, might have enabled their encounter. The large-scale study is based on the comparison and analysis of genetic material of all bear species that still exist. The results have been published recently in the journal Evolution and Molecular Biology.

American black bear. Copyright: Tobias Bidon

If in documentaries or in the zoo - everyone has seen and knows about brown bears, polar bears and pandas. However, there are several other bear species in Asia and South America that are less well-known, such as the sloth bear, the Asiatic or the spectacled bear. There are eight bear species that still exist worldwide. Despite many years of research, the exact relationships between them remain unresolved.

Who with whom? Polar bear and brown have hybridized
Previous analyses of genetic material of polar bears and brown bears have proven already that the two species have hybridized during their long evolutionary history. This behavior can still be observed today and the ongoing climate change drives the bear even closer. It is therefore likely that there have been similar exchanges of genetic material between other species of the bear family.

... as well as brown bears and black bears
To shed light on this, a team of the German Biodiversity and Climate Research Centre (BiK-F) and the Goethe University Frankfurt in cooperation with colleagues from the US have now analyzed certain genome parts of all bear species alive today. "We were able to show that several bear species have hybridized during their evolutionary history. The exchange can still be traced in the genetic makeup of today's bears," says the lead author of the study, Verena Kutschera (BiK-F). This mix-up makes it difficult to classify some gene fragments as belonging to a particular species.

Beringia land bridge serving as an intercontinental meeting point
Surprisingly, several bear species which nowadays live on different continents have also taken part in the mating and thus gene exchange. This may have been possible because the significantly lower sea level during past ice ages resulted in a land bridge between Asia and North America, the Beringia land bridge. Thus the ancestors of today’s bear species, e.g. of the Asiatic black bear and the American black bear, had the opportunity to meet and to mate.

Darwin’s species tree is insufficient to map complicated relationships
All eight bear species that occur today have well adapted to their present habi-tat and differ physically very much. A prime example for this is polar bears and black bears. Nevertheless, the speciation of some individual genes has not finished yet which additionally complicates the research of the evolution of bears.

With new molecular methods more gene parts might be discovered in the genomes of mammal species that could originate from other species. Apparently separate genetic lineages turn out to have merged – sometimes repeatedly – during the evolutionary history and exchanged genetic material with each other. "The traditional pedigree already used by Darwin is not always suitable to map evolutionary history in full detail. So-called phylogenetic networks a more useful to depict the genetic mix-up that we have found ", comments evolutionary biologist Prof. Dr. Axel Janke, BiK-F, leader of the research team. The study demonstrates that evolution often is not a linear process; thanks to modern molecular methods it’s complex processes are finally revealed.

Kutschera, V. et al. Bears in a forest of gene trees: Phylogenetic inference is complicated by incomplete lineage sorting and gene flow – Molecular Biology and Evolution, DOI: 10.1093/molbev/msu186

For further information please contact:

Prof. Dr. Axel Janke
LOEWE Biodiversity and Climate Research Centre (BiK-F)
Tel. +49 (0)69 7542 1842

Verena Kutschera
LOEWE Biodiversity and Climate Research Centre (BiK-F)
Tel. +49 (0)69 7542 1828

Sabine Wendler
LOEWE Biodiversity and Climate Research Centre (BiK-F)
Press officer
Tel. +49 (0)69 7542 1838

LOEWE Biodiversität und Klima Forschungszentrum, Frankfurt am Main
With the objective of analysis the complex interactions between biodiversity and climate through a wide range of methods, the Biodiversität und Klima Forschungszentrum [Biodiversity and Climate Research Centre] (BiK‐F) has been funded since 2008 within the context of the Landes‐ Offensive zur Entwicklung Wissenschaftlichökonomischer Exzellenz (LOEWE) of the Land of Hessen. The Senckenberg Gesellschaft für Naturforschung and Goethe University in Frankfurt as well as other, directly involved partners, co‐operate closely with regional, national and international institutions in the fields of science, resource and environmental management, in order to develop projections for the future and scientific recommendations for sustainable action. For further details, please visit www.bik‐

Sabine Wendler | Senckenberg

Further reports about: Beringia BiK-F Biodiversity Biodiversität Biology Climate Evolution Molecular Senckenberg history relationships

More articles from Life Sciences:

nachricht Make way for the mini flying machines
21.03.2018 | American Chemical Society

nachricht New 4-D printer could reshape the world we live in
21.03.2018 | American Chemical Society

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

TRAPPIST-1 planets provide clues to the nature of habitable worlds

21.03.2018 | Physics and Astronomy

The search for dark matter widens

21.03.2018 | Materials Sciences

Natural enemies reduce pesticide use

21.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>