Forum for Science, Industry and Business

Climate change driving tropical birds to higher elevations

The study, published Thursday in the peer-reviewed online journal PLoS ONE, finds that the birds aren't migrating as rapidly as scientists previously anticipated, based on recorded temperature increases.

The animals instead may be tracking changes in vegetation, which can only move slowly via seed dispersal.

"This is the first study to evaluate the effects of warming on the elevation ranges of tropical birds," said Stuart Pimm, Doris Duke Professor of conservation ecology at Duke's Nicholas School of the Environment and a co-author of the study. "It provides new evidence of their response to warming, but also shows there is a delay in their response."

Evidence from temperate areas, such as North America and Europe, shows that many animal and plant species are adapting to climate change by migrating northward, breeding earlier or flowering earlier in response to rising temperatures.

"However, our understanding of the response of tropical birds to warming is still poor," said German Forero-Medina, a Ph.D. student at Duke's Nicholas School who is lead author of the new study. "Moving to the north doesn't help them, because tropical temperatures do not change very much with latitude. So moving up to higher elevations is the only way to go, but there are few historical data that can serve as baselines for comparison over time."

What is going on with tropical species at higher altitudes is important, Forero-Medina said, because about half of all birds species live 3,500 feet or more above sea level, and of these species, more than 80 percent may live within the tropics.

In 2010, the authors of the new study and a team of biologists participated in an expedition to the summit of the remote Cerros del Sira mountains in central Peru – a place visited by only a few ornithologists on prior occasions. The complex topography, geology and climate of the mountains have produced isolated patches of habitat with unique avian communities and distinct taxa.

Forero-Medina and his colleagues used survey data collected on bird species in the region in the 1970s by John Terborgh, research professor emeritus at Duke, to compare past and present distributions.

"Using John Terborgh's groundbreaking data -- the first ever collected from this region --gave us a unique opportunity to understand the effects of 40 years of warming on tropical birds," Forero-Medina says.

The biologists found that although the ranges of many bird species have shifted uphill since Terborgh's time, the shifts fell short of what scientists had projected based on temperature increases over the four decades.

"This may be bad news," Pimm said. "Species may be damned if they move to higher elevations to keep cool and then simply run out of habitat. But, by staying put, they may have more habitat but they may overheat."

CITATION: "Elevational Ranges of Birds on a Tropical Montane Gradient Lag Behind Warming Temperatures" German Forero-Medina, John Terborgh, S. Jacob Socolar & Stuart L. Pimm. PLoS ONE, Dec. 7, 2011.

Tim Lucas | EurekAlert!
Further information:
http://www.duke.edu

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...