Navigation Links
Land iguanas under continuing threat on Galapagos archipelago
Date:11/26/2008

The Galpagos Islands, which provided impetus and inspiration for Charles Darwin's seminal work, "On the Origin of Species", are home to unique populations of reptiles. Since the time of man's first visit in the 16th century to this crucial incubator for evolutionary theory, the islands' native plants and animals have faced grave challenges, including severe pressures from introduced species, habitat destruction and predation by man himself.

In some instances, this has led to reduced populations and even extinction. In the 20th century, conservation efforts began, but according to new research published this week in the scientific journal Molecular Ecology considerably more must be done to insure the long-term survival of land-dwelling iguanas on the archipelago.

In their new article, "Galapagos Land Iguanas Remnant Populations," an international coalition of scientists, led by Michel Milinkovitch, from the University of Geneva, Switzerland, detail their near-decade-long effort to assess the population genetics of land iguanas on the six islands where the reptiles occur today.

Population genetics is a cornerstone of modern evolutionary synthesis. It employs principles of molecular genetics and sophisticated data analysis to identify populations and characterize the genetic diversity within and the levels of genetic differentiation among these evolutionarily significant groups. Changes are influenced by the evolutionary forces of natural selection, genetic drift, mutation and gene flow. Scientists obtain blood or tissue samples from subjects and examine multiple loci across their genome. In so doing, researchers are able to draw conclusions regarding relationships, genetic diversity and genetic drift among various populations.

Galpagos land iguanas diverged from the famous Galpagos marine iguanas 10 to 20 million years ago, and there are currently two recognized species of terrestrial iguanas; Conolophus subcristatus and C. pallidus.

Beginning in the 1930s, and continuing through the 1980s, various threatened populations of land iguanas were relocated from one island habitat to another, or were subject to captive breeding and reintroduction programs. Combined with the eradication of invasive species at some locations, this patchwork of dedicated conservation efforts by the Charles Darwin Foundation and the Galpagos National Park Service has undoubtedly preserved some native species from extinction, but unfortunately the records of these activities were not always detailed. As a result, the genetic diversity of captive and reintroduced populations is uncertain.

Given that genetic diversity within and relationships among populations are crucial for long-term species survival, the authors investigated genetic variation at nine nuclear microsatellite loci among more than 700 land iguanas from six island habitats. For comparison, the information obtained was compared with similar information gathered from 20 marine iguanas. This represents the first time that extensive and modern molecular genetic analyses have been applied to the study of these unique terrestrial reptiles. Results revealed four distinct "clusters" of iguanas, including two potential new species. Results also revealed that, while some populations enjoy robust genetic diversity, others do not. As such, they are at increased risk from any future changes in environmental pressures.

As noted by the authors, "Molecular data could prove of paramount interest for improving management of [off-site] captive populations and for guiding the development of proper [natural habitat] population survival and habitat management plans for this spectacular reptile."


'/>"/>

Contact: Tim Vines
managing.editor@molecol.com
778-989-8755
Wiley-Blackwell
Source:Eurekalert

Related biology news :

1. Global climate change: The impact of El Nio on Galpagos marine iguanas
2. Global climate change: The impact of El Niño on Galápagos marine iguanas
3. Dancing atoms now understood
4. Using water to understand human society, from the industrial revolution to global trade
5. Research-based undergraduate course expands beyond Washington University
6. Understanding how oxidative stress impairs endothelial progenitor cell function
7. Photos: Turn Your Couch into a Disney Ride for Under $300
8. Small satellite takes on large thunderstorms
9. Complex systems and Mars missions help understand how life began
10. NYU biologist Bonneau named among 20 "visionary" scientists under 40 by Discover magazine
11. NSF grant to launch undergrads from Case Western Reserve into math and science teaching
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2016)... and BANGALORE, India , April 28, 2016 ... a product subsidiary of Infosys (NYSE: INFY ), ... a global partnership that will provide end customers ... mobile banking and payment services.      (Logo: ... innovation area for financial services, but it also plays a ...
(Date:4/26/2016)... , April 27, 2016 ... "Global Multi-modal Biometrics Market 2016-2020"  report to their ... , The analysts forecast the global ... of 15.49% during the period 2016-2020.  ... of sectors such as the healthcare, BFSI, transportation, ...
(Date:4/15/2016)... 15, 2016 Research and ... Biometrics Market 2016-2020,"  report to their offering.  , ... , ,The global gait biometrics market is expected ... the period 2016-2020. Gait analysis generates ... be used to compute factors that are not ...
Breaking Biology News(10 mins):
(Date:5/3/2016)... (PRWEB) , ... May 03, 2016 , ... ... leading fertility clinics and IVF laboratories. A contingency of reproductive endocrinologists, including ... men and women experiencing infertility and to help them build families. , Ovation ...
(Date:5/2/2016)... , ... May 02, 2016 , ... ... report on the pre-launch success of their revolutionary, veterinarian-designed product for indoor cats. ... stalk, trap, and play with their food the way nature intended. NoBowls make ...
(Date:4/29/2016)... April 29, 2016 According ... Market Research "Separation Systems for Commercial Biotechnology Market ... and Forecast 2015 - 2023", the separation systems ... 10,665.5 Mn in 2014 and is projected to ... to 2023 to reach US$ 19,227.8 Mn in ...
(Date:4/29/2016)... 2016 Elekta is pleased to ... its industry-leading treatment planning software, is available for clinical ... version 5.11 provides significant performance speed enhancements ... up to four times faster than in previous versions ... gold standard Monte Carlo algorithm, ...
Breaking Biology Technology: