Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The Tree of Life Has Lost a Branch

22.01.2008
Norwegian and Swiss biologists have made a startling discovery about the relationship between organisms that most people have never heard of. The Tree of Life must be re-drawn, textbooks need to be changed, and the discovery may also have significant impact on the development of medicines.

The discovery by Norwegian and Swiss researchers has gained attention from biologists worldwide. The findings come from the largest ever genetic comparison of higher life forms on the planet. Of 5000 genes examined, researchers identified 123 common genes from all known groups of organisms; these common genes have been studied more closely. The study has required long hours of work from the researchers and an enormous amount of computing resources—supplied through a large network of computers at the University of Oslo.

Lost a Branch

“The results were pretty astounding. All non-bacterial life on Earth—called eukaryotic life— can now be divided into four main groups instead of the five groups that we have been working with up to now,” says Kamran Shalchian-Tabrizi, an associate professor from the University of Oslo’s Department of Biology who has also worked with the Department of Zoology and Animal Biology and the Department of Genetic Medicine and Development, at the University of Geneva, Switzerland.

The Tree of Life (see illustration) has, through the discovery that the two formerly separated branches share a similar evolutionary history, lost one of its branches, and this will both improve and simplify quite a bit of scientific work in the future.

Important Discovery

“Kinship says a lot about shared traits. Our findings can be important in many fields, such as in the study of the development of life and in the manufacture of new medicines” says Shalchian-Tabrizi in an interview with the University of Oslo’s research magazine Apollon.

“Our knowledge of organisms and the development of medicines are often based on comparative studies across species. It is, therefore, essential that we know the relationships between the largest groups in the great diversity of eukaryotes,” he adds.

The research group has, for example, found that brown algae and silica algae, and groups of single cell organisms like the malaria parasite, marine foraminifera, and the green sun animalcule (acanthocystis turfacea) actually belong to the same group. Previously, these species were thought to be completely unrelated.

“The work that we published in the August edition of PLoS ONE (a leading open access journal found on the internet) means that the description of the Tree of Life must be revised in new textbooks,” says Professor Kjetill S. Jakobsen from the University of Oslo’s Centre for Ecological and Evolutionary Synthesis (CEES). He is also a member of the Microbial Evolution Research Group (MERG), led by Shalchian-Tabrizi, at the Department of Biology. MERG is one of 16 groups that the Faculty of Mathematics and Natural Sciences believes may have the potential to develop into new Centres of Excellence.

The New Branch

All life on Earth can be divided into two essentially different life forms—eukaryotes and prokaryotes. The eukaryotes gather their genetic material in a nucleus, while the prokaryotes (bacteria and archaea) have their genetic material floating freely in the cell. Eukaryotic organisms—such as humans—can, as a result of the new findings, be divided into the following four categories:

•Plants (green and red algae, and plants)

•Opisthokonts (amoebas, fungi, and all animals—including humans)

•Excavates (free-living organisms and parasites)

•SAR (the new main group, an abbreviation of Stramenophiles, Alveolates,
and Rhizaria, the names of some of its members)
“The SAR group has to some extent been identified earlier, but we could not know if it was a correct observation because we lacked statistical data. To get that data, we first had to reconstruct the entire eukaryote tree with the help of these 123 genes. Chromalveolates and rhizaria were clearly separate groups until we published our results,” says Shalchian-Tabrizi.

“To make the picture a little less clear, one branch of chromalveolates is still in no man’s land. It may be that these also belong to SAR, but we will require additional genes and genomes to study this. We have set our sights on doing that in the course of the next few years,” he adds.

Fewer Events

“The Tree of Life tells the story of life on Earth, and our research can say something about how quickly life developed. Our discovery suggests that there were fewer big “events” than we have previously assumed in the development of higher life forms. The more we know about the branches on the Tree of Life, the more we can find out about life’s Big Bang, the beginning of life on Earth,” says Shalchian-Tabrizi.

Three billion years ago, there was only bacteria and Archaea. Eukaryotic life, which comprises all multi-celled organisms, developed in the sea—probably between 1.2 and 1.6 billion years ago. It was not before about 500 million years ago that the first creatures crept onto land.

“By digging down into the historical layers with the help of phylogenetic reconstruction, where we can find out about kinship between organisms at the genetic level and we can find answers to questions about how new traits developed. We are working, in a matter of speaking, with genetic archaeology. In this manner, we can also discover the cause of the Earth’s biological diversity,” says Jakobsen.

Text: Lars Hoff
Photo: Ståle Skogstad
Translation: Alan Louis Belardienlli

Kamran Shalchian-Tabrizi | alfa
Further information:
http://www.bio.uio.no

More articles from Ecology, The Environment and Conservation:

nachricht Upcycling 'fast fashion' to reduce waste and pollution
03.04.2017 | American Chemical Society

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

Researchers invent process to make sustainable rubber, plastics

25.04.2017 | Materials Sciences

Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017

25.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>