Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New research on rapidly-disappearing ancient plant offers hope for species recovery

14.07.2010
Genetic analysis of Guam's cycads shows promising genetic diversit

Cycads, "living fossil" descendents of the first plants that colonized land and reproduced with seeds, are rapidly going extinct because of invasive pests and habitat loss, especially those species endemic to islands.

But new research on Cycas micronesica published recently as the cover article in Molecular Ecology calls into question the characterization of these plants as relicts (leftovers of formerly abundant organisms), and gives a glimpse into how the remaining plants—those that survived the loss of more than 90% of their population—can be conserved and managed. By sampling what is left of C. micronesica on Guam, researchers, including some from the American Museum of Natural History, found moderate genetic variation within local populations and different levels of gene flow between populations.

"Cycas micronesica is one of the most ecologically important plants on Guam and nearby islands, and it is now rapidly disappearing," says Angélica Cibrián-Jaramillo, a researcher at the American Museum of Natural History and at The New York Botanical Garden. "But with new genomic tools we developed microsatellite markers to quickly assess individual plants. This technique is ideal for species that need quick answers for conservation reasons." Microsatellite markers are short genetic sequences typically used to determine how individuals are related to each other (kinship) and other population studies.

Cycads have been around for about 300 million years and are among the first spermatophytes, or plants that reproduce with seeds. Although this group's large crowns of feathery compound leaves was once common, cycads now number about 300 species throughout the world, and about half of these are threatened or endangered. C. micronesica is found on four island groups in Micronesia.

Within four years, the millions of C. micronesica on Guam were reduced by more than 90%. The primary culprit was an insect that often parasitizes plants (in this case, a scale) that invaded Guam in 2003, although other invasive species including butterflies and feral pigs are contributing to plant mortality. The invasive species are also spreading to other islands.

"This ecological disaster is typical on islands," says Thomas Marler, professor at the University of Guam. "There has been a cascade of invasive species in a short time. This study will give conservation groups information about how to manage the surviving plants: the most efficient way to establish nurseries and where to collect seeds, and how to reintroduce them if the [invasive] insect is brought under control."

For this study, Marler collected leaf samples from all C. micronesica habitats on Guam, and Cibrián-Jaramillo found 18 genetic populations among 24 locations. The results showed that local populations are not genetically poor but instead have moderate genetic variation with some inbreeding, which is what would be expected in longer-lived plants with similar seed dispersal. The amount of genetic flow between Guam's populations was low but very dynamic within regions in the island, which means that plants are similar genetically and the observed variation points to patterns of seed dispersal. Cycas micronesica plants in the north are more likely to be related to each other, while populations in the south are genetically different from each other. This contrast is most likely due to southern Guam's more fragmentary forests, more rivers for seed transportation (C. micronesica seeds are one of the few cycad seeds that float), and the smaller size of seeds, which can be dispersed to greater distances.

"We hope that these results from the plant perspective will fit into the management of invasive insects in general, which is one of the most important drivers of biodiversity loss worldwide and very costly economically," says Rob DeSalle, curator at the American Museum of Natural History who works in the Sackler Institute for Comparative Genomics.

In addition to Cibrián-Jaramillo, Marler, and DeSalle, authors of this paper (Molecular Ecology 19, 2364-2379, doi 10.1111/j.1365-294X.2010.04638.x) include Aidan Daly of the Museum's Sackler Institute for Comparative Genomics and Eric Brenner of New York University. The research was funded by the U.S. Department of Agriculture and the Lewis B. and Dorothy Cullman Program for Molecular Systematics at the American Museum of Natural History and The New York Botanical Garden.

Kristin Elise Phillips | EurekAlert!
Further information:
http://www.amnh.org

More articles from Ecology, The Environment and Conservation:

nachricht Scientists on the road to discovering impact of urban road dust
18.01.2018 | University of Alberta

nachricht Gran Chaco: Biodiversity at High Risk
17.01.2018 | Humboldt-Universität zu Berlin

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: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>