Navigation Links
'Living fossil' tree contains genetic imprints of rain forests under climate change
Date:10/30/2008

ANN ARBOR, Mich.---A "living fossil" tree species is helping a University of Michigan researcher understand how tropical forests responded to past climate change and how they may react to global warming in the future.

The research appears in the November issue of the journal Evolution.

Symphonia globulifera is a widespread tropical tree with a history that goes back some 45 million years in Africa, said Christopher Dick, an assistant professor of ecology and evolutionary biology who is lead author on the paper. It is unusual among tropical trees in having a well-studied fossil record, partly because the oil industry uses its distinctive pollen fossils as a stratigraphic tool.

About 15 to 18 million years ago, deposits of fossil pollen suggest, Symphonia suddenly appeared in South America and then in Central America. Unlike kapok, a tropical tree with a similar distribution that Dick also has studied, Symphonia isn't well-suited for traveling across the ocean---its seeds dry out easily and can't tolerate saltwater. So how did Symphonia reach the neotropics? Most likely the seeds hitched rides from Africa on rafts of vegetation, as monkeys did, Dick said. Even whole trunks, which can send out shoots when they reach a suitable resting place, may have made the journey. Because Central and South American had no land connection at the time, Symphonia must have colonized each location separately.

Once Symphonia reached its new home, it spread throughout the neotropical rain forests. By measuring genetic diversity between existing populations, Dick and coworker Myriam Heuertz of the Universit Libre de Bruxelles were able to reconstruct environmental histories of the areas Symphonia colonized.

"For Central America, we see a pattern in Symphonia that also has been found in a number of other species, with highly genetically differentiated populations across the landscape," Dick said. "We think the pattern is the result of the distinctive forest history of Mesoamerica, which was relatively dry during the glacial period 10,000 years ago. In many places the forests were confined to hilltops or the wettest lowland regions. What we're seeing in the patterns of genetic diversity is a signature of that forest history."

In the core Amazon Basin, which was moist throughout the glacial period, allowing for more or less continuous forest, less genetic diversity is found among populations, Dick said. "There's less differentiation across the whole Amazon Basin than there is among sites in lower Central America."

The study is the first to make such comparisons of genetic diversity patterns in Central and South America. "We think similar patterns will be found in other widespread species," Dick said.

Learning how Symphonia responded to past climate conditions may be helpful for predicting how forests will react to future environmental change, Dick said.

"Under scenarios of increased warmth and drying, we can see that populations are likely to be constricted, particularly in Central America, but also that they're likely to persist, because Symphonia has persisted throughout Central America and the Amazon basin. That tells us that some things can endure in spite of a lot of forest change. However, past climate changes were not combined with deforestation, as is the case today. That combination of factors could be detrimental to many species---especially those with narrow ranges---in the next century."


'/>"/>

Contact: Nancy Ross-Flanigan
rossflan@umich.edu
734-647-1853
University of Michigan
Source:Eurekalert  

Related biology news :

1. TB bacterium uses its sugar coat to sweeten its chances of living in lungs
2. NSF funds new Center for the Physics of Living Cells at Illinois
3. Buckyballs have high potential to accumulate in living tissue
4. Living sensor can warn of arsenic pollution
5. Nothing stops an expert in the art of living
6. Simian foamy virus found in several people living and working with monkeys in Asia
7. Living fossils have long- and short-term memory
8. Mouse study: When it comes to living longer, its better to go hungry than go running
9. Worlds oldest living tree discovered in Sweden
10. Novel living system recreates predator-prey interaction
11. Harvard researchers publish MRI images of genes in action in the living brain
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
'Living fossil' tree contains genetic imprints of rain forests under climate change
(Date:4/11/2017)... N.Y. , April 11, 2017 ... fingerprints, but researchers at the New York University ... College of Engineering have found that partial similarities ... security systems used in mobile phones and other ... thought. The vulnerability lies in the ...
(Date:4/5/2017)... SEATTLE , April 5, 2017  The Allen ... the Allen Cell Explorer: a one-of-a-kind portal and dynamic ... large-scale 3D imaging data, the first application of deep ... edited human stem cell lines and a growing suite ... the platform for these and future publicly available resources ...
(Date:4/4/2017)... 4, 2017   EyeLock LLC , a leader ... United States Patent and Trademark Office (USPTO) has issued ... linking of an iris image with a face image ... the company,s 45 th issued patent. ... timely given the multi-modal biometric capabilities that have recently ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... ... October 12, 2017 , ... AMRI, ... and biotechnology industries to improve patient outcomes and quality of life, will now ... testing are being attributed to new regulatory requirements for all new drug products, ...
(Date:10/11/2017)... ... October 11, 2017 , ... ComplianceOnline’s Medical Device Summit ... 7th and 8th June 2018 in San Francisco, CA. The Summit brings together current ... several distinguished CEOs, board directors and government officials from around the world to address ...
(Date:10/11/2017)... ... October 11, 2017 , ... A ... pregnancy rates in frozen and fresh in vitro fertilization (IVF) transfer ... age to IVF success. , After comparing the results from the fresh and ...
(Date:10/10/2017)... ... October 10, 2017 , ... Dr. Bob Harman, founder ... local San Diego Rotary Club. The event entitled “Stem Cells and ... had 300+ attendees. Dr. Harman, DVM, MPVM was joined by two human doctors: ...
Breaking Biology Technology: