LSU scientists shed new light on how species diverge
Birds that are related, such as Darwin's finches, but that vary in beak size and behavior specially evolved to their habitat are examples of a process called speciation. It has long been thought that dramatic changes in a landscape like the formation of the Andes Mountain range or the Amazon River is the main driver that initiates species to diverge.
However, a recent study shows that speciation occurred much later than these dramatic geographical changes. Researchers from LSU's Museum of Natural Science have found that time and a species' ability to move play greater parts in the process of speciation. This research was published today in the print edition of Nature.
"The extraordinary diversity of birds in South America is usually attributed to big changes in the landscape over geological time, but our study suggests that prolonged periods of landscape stability are more important," said Robb Brumfield, LSU Museum of Natural Science director and Roy Paul Daniels professor in the Department of Biological Sciences, one of the lead authors.
Brumfield and his colleagues examined the genealogy of 27 species of birds in the most bio-diverse region in the world, the Neotropics, which extends from southern Mexico through Central America to southern Brazil and includes the Amazon rainforest.
"By using detailed sampling of many bird lineages, we were able to get a clearer and larger picture of when and how species formed within those lineages," Brumfield said.
The genetic data showed multiple accounts of species divergence, from nine to 29 different instances across the Andes Mountains that varied over time. This shows that rather than being the primary cause of speciation, the formation of the Andes Mountains had an indirect effect on diversification as a semi-permeable barrier.
The researchers then investigated how the history and ecology affected speciation among the 27 lineages of birds. They discovered the longer length of time a species can inhabit an area, the more likely it will disperse and diverge. Also, the less mobility a species has, the more likely it will diverge as well.
For example, birds restricted to the forest floor showed significantly higher species diversity than birds that inhabited the forest's open canopy. These findings have conservation ramifications. If a species cannot inhabit the same area for an extended time, it will not have the opportunity to evolve and continue.
"Our results suggest that human alterations of the landscape can effectively kill the speciation process," Brumfield said.
This research was funded by the National Science Foundation. Other institutions involved in this research include the American Museum of Natural History, City College of New York, Museu Paraense Emílio Goeldi in Brazil, Universidad de los Andes in Colombia, Universidad Central de Venezuela, Colección Ornithológica Phelps, University of California Los Angeles and the University of Georgia Athens.
The thousands of samples used in this study represent the culmination of more than 30 years of field expeditions led by generations of LSU students and scientists, plus similar work done by ornithologists at other research institutions.
The mission of the LSU Museum of Natural Science is the acquisition, preservation and study of research collections by museum faculty, staff and students to generate knowledge of regional and global biodiversity, geological history and human history/prehistory for the benefit of the people of Louisiana, the nation and the world. For more information on the museum, visit http://www.museum.lsu.edu/
Follow the museum's Twitter, @LSU_MNS. Like the museum's LSU Big Day Peru Facebook for updates as the international award-winning birding team prepares to break the world Big Day record, http://www.facebook.com/LSUBigDay
The mission of the Department of Biological Sciences is to create and disseminate new knowledge in the biological sciences through research; to provide for its majors the highest quality, nationally recognized, graduate and undergraduate educational programs; to provide exceptional science training to support the university's general education requirements; and to contribute expertise in support of science education in the community, including the use of available resources to improve K-12 science outreach. For more information, visit http://www.biology.lsu.edu/
Alison Satake | EurekAlert!
Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory
Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine