Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

First phylogeographic study of a rainforest tree

08.12.2003


In species-rich rainforests of the New World tropics most trees have broad geographic distributions–from Mexico to Bolivia and sometimes to the West Indies. Either they have excellent dispersal abilities, or they established broad ranges prior to the formation of present geographic barriers. In a study featured in American Naturalist, Christopher Dick, Kobinah Abdul-Salim and Eldredge Bermingham address these questions in the first phylogeographic study of a rainforest tree.



The morphology of the study species, Symphonia globulifera (Clusiaceae) is uniform across a natural range that includes the New World tropics and Africa. Symphonia globulifera also has a detailed fossil pollen record, which the authors used to calibrate a molecular clock for DNA sequences obtained from African and Neotropical populations and to estimate when these populations were separated. The study revealed that, although trees from different populations look the same, the evolutionary history of these populations is probably quite distinct.

Although marine dispersal of S. globulifera is considered improbable because it has salt-intolerant seeds, the authors demonstrate that Symphonia expanded into Mesoamerica, the Amazon basin and the West Indies via oceanic currents at least three times. The three major New World clades – found in Mesoamerica, the Amazon basin, and the West Indies – diverged over 15 million years ago, and appear to have been genetically isolated ever since, giving Symphonia globulifera the status of "living fossil".


Panama contained the largest number of genetically distinctive populations, in contrast to Amazon basin Symphonia, which displayed no genetic differentiation across 2500 km of lowland forest. The authors suggest that strong phylogeographic structure in the Panamanian Isthmus stems from its history as a land bridge between Central America, South America, and the proto-Isthmian archipelago of islands, which were connected approximately 3 million years ago.

The authors suggest that same history may explain the high level of beta diversity (changes in species composition among sites) of rainforest trees in Panama, in contrast to western Amazon (Condit et al. Science 2002 v292, 666-669). While ecologists attribute the beta diversity in Panama to local adaptations to varied habitats, the diversity may also reflect the incomplete mixing of independently evolved floras during the Great American Biotic Interchange across the Isthmus of Panama.


Ref. Molecular systematics reveals tertiary diversification of a widespread tropical rainforest tree. Christopher Dick, Kobinah Abdul-Salim, and Eldredge Bermingham. American Naturalist, December, 2003.

Christopher Dick | EurekAlert!
Further information:
http://www.si.edu/

More articles from Life Sciences:

nachricht Bare bones: Making bones transparent
27.04.2017 | California Institute of Technology

nachricht Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

All articles from Life Sciences >>>

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

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>