Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Research shows that coldness triggers northward flight in migrating monarch butterflies

22.02.2013
Findings suggest that the monarch migration cycle may be vulnerable to global climate change

Each fall millions of monarch butterflies from across the eastern United States begin a southward migration in order to escape the frigid temperatures of their northern boundaries, traveling up to 2,000 miles to an overwintering site in a specific grove of fir trees in central Mexico.

Surprisingly, a new study by scientists at the University of Massachusetts Medical School published in Current Biology, suggests that exposure to coldness found in the microenvironment of the monarch's overwintering site triggers their return north every spring. Without this cold exposure, the monarch butterfly would continue flying south.

These findings help explain why monarch butterflies transverse such long distances to overwinter at a relatively small region roughly 300 square miles in size atop frost-covered mountains. Upon arrival in November, the monarchs begin to congregate in tightly packed clusters in a few isolated locations in the high altitude coniferous forests. Both the clustering and the forest cover provide a microenvironment that protects against environmental extremes – the temperature remains low enough to keep metabolic demands low but not cold enough to cause freezing – and ultimately triggers their return north in the spring.

It also suggests that these delicate creatures may be influenced by and vulnerable to global climate changes, say researchers. "The temperature of the microenvironment at the overwintering sites is a critical component for the completion of the migration cycle," said Steven M. Reppert, MD, professor of neurobiology and senior author of the study. "Without this thermal stimulus, the annual migration cycle would be broken, and we could have lost one of the most intriguing biological phenomena in the world."

Though accomplished in a single calendar year, it takes at least three generations of monarch butterflies to complete a single migratory journey. The monarchs that return to Mexico each year have never been to the overwintering sites before, and have no relatives to follow on their way. The biological and genetic mechanisms underlying their incredible journey have intrigued scientists for generations.

Earlier work by Reppert's group found that monarchs rely on a time-compensated sun compass to direct their navigation south. Their new research shows that those same systems are responsible for guiding them north each spring.

This alone, however, didn't explain what was triggering the change in direction each spring. To find out, Patrick Guerra, a postdoctoral fellow in Reppert's lab at UMass Medical School and first author on the Current Biology study, collected wild monarchs at the start of their migration in the fall and subjected the monarchs to the same temperature and light levels they would experience in their overwintering ground in Mexico. When the monarchs were studied in a flight simulator 24 days later, instead of resuming their southward journey, the butterflies headed north.

Further study confirmed that changes in temperature alone altered the flight direction of the monarch butterflies. Those subjected to cold oriented north; monarchs who were protected from the cold would continue to orient south.

These findings, coupled with newly available genetic and genomic tools for monarchs, will lead to new insights about the biological processes underlying their remarkable migratory journey.

"The more we learn, the clearer it becomes that the monarch migration is a uniquely fragile biological process," said Reppert. "Understanding how it works means we'll be better able to protect this iconic system from external threats such as global warming."

About the University of Massachusetts Medical School

The University of Massachusetts Medical School, one of the fastest growing academic health centers in the country, has built a reputation as a world-class research institution, consistently producing noteworthy advances in clinical and basic research. The Medical School attracts more than $250 million in research funding annually, 80 percent of which comes from federal funding sources. The mission of the Medical School is to advance the health and well-being of the people of the commonwealth and the world through pioneering education, research, public service and health care delivery with its clinical partner, UMass Memorial Health Care. For more information, visit www.umassmed.edu.

Jim Fessenden | EurekAlert!
Further information:
http://www.umassmed.edu

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>