Science Current Events | Science News | Brightsurf.com
 

New Study Is First to Show That Pesticides Can Induce Morphological Changes in Vertebrate Animals, Says Pitt Researcher

April 03, 2012
PITTSBURGH- The world's most popular weed killer, Roundup®, can cause amphibians to change shape, according to research published today in Ecological Applications.

Rick Relyea, University of Pittsburgh professor of biological sciences in the Kenneth P. Dietrich School of Arts and Sciences and director of Pitt's Pymatuning Laboratory of Ecology, demonstrated that sublethal and environmentally relevant concentrations of Roundup® caused two species of amphibians to alter their morphology. According to Relyea, this is the first study to show that a pesticide can induce morphological changes in a vertebrate animal.

Relyea set up large outdoor water tanks that contained many of the components of natural wetlands. Some tanks contained caged predators, which emit chemicals that naturally induce changes in tadpole morphology (such as larger tails to better escape predators). After adding tadpoles to each tank, he exposed them to a range of Roundup® concentrations. After 3 weeks, the tadpoles were removed from the tanks.

"It was not surprising to see that the smell of predators in the water induced larger tadpole tails," says Relyea. "That is a normal, adaptive response. What shocked us was that the Roundup® induced the same changes. Moreover, the combination of predators and Roundup® caused the tail changes to be twice as large." Because tadpoles alter their body shape to match their environment, having a body shape that does not fit the environment can put the animals at a distinct disadvantage.

Predators cause tadpoles to change shape by altering the stress hormones of tadpoles, says Relyea. The similar shape changes when exposed to Roundup® suggest that Roundup® may interfere with the hormones of tadpoles and potentially many other animals.

"This discovery highlights the fact that pesticides, which are important for crop production and human health, can have unintended consequences for species that are not the pesticide's target," says Relyea. "Herbicides are not designed to affect animals, but we are learning that they can have a wide range of surprising effects by altering how hormones work in the bodies of animals. This is important because amphibians not only serve as a barometer of the ecosystem's health, but also as an indicator of potential dangers to other species in the food chain, including humans."

For two decades, Relyea has studied community ecology, evolution, disease ecology, and ecotoxicology. He has authored more than 80 scientific articles and book chapters and has presented research seminars around the world. For more information about his laboratory, visit www.pitt.edu/~relyea/

University of Pittsburgh


Related Pesticides Current Events and Pesticides News Articles


Water covers 70 percent of the Earth's surface, but only a fraction is fresh
Fresh water--connecting and sustaining all aspects of life on Earth, including food and energy--is in great danger. Moreover, scientists are worried not only about fresh water; they worry that we are not worried enough about fresh water, especially in light of growing concern over recent events, such as the prolonged California drought.

Research could lead to protective probiotics for frogs
In research that could lead to protective probiotics to fight the "chytrid" fungus that has been decimating amphibian populations worldwide, Jenifer Walke, PhD, a postdoctoral researcher at Virginia Tech University, Blacksburg, and her collaborators have grown bacterial species from the skin microbiome of four species of amphibians.

Safeguarding the greater good
Gene drives are genetic elements - found naturally in the genomes of most of the world's organisms - that increase the chance of the gene they carry being passed on to all offspring, and thus, they can quickly spread through populations.

How bees naturally vaccinate their babies
When it comes to vaccinating their babies, bees don't have a choice -- they naturally immunize their offspring against specific diseases found in their environments. And now for the first time, scientists have discovered how they do it.

WSU researchers investigate effect of environmental epigenetics on disease and evolution
Washington State University researchers say environmental factors are having an underappreciated effect on the course of disease and evolution by prompting genetic mutations through epigenetics, a process by which genes are turned on and off independent of an organism's DNA sequence.

Pesticides found in most pollen collected from foraging bees in Massachusetts
More than 70% of pollen and honey samples collected from foraging bees in Massachusetts contain at least one neonicotinoid, a class of pesticide that has been implicated in Colony Collapse Disorder (CCD), in which adult bees abandon their hives during winter, according to a new study from Harvard T.H. Chan School of Public Health.

Fighting mosquito resistance to insecticides
Controlling mosquitoes that carry human diseases is a global health challenge as their ability to resist insecticides now threatens efforts to prevent epidemics.

Study finds autism, ADHD run high in children of chemically intolerant mothers
A new study from The University of Texas Health Science Center at San Antonio found that mothers with chemical intolerances are two to three times more likely than other women to have a child with autism spectrum disorder (ASD) or attention deficit hyperactivity disorder (ADHD).

Flatworms could replace mammals for some toxicology tests
Laboratories that test chemicals for neurological toxicity could reduce their use of laboratory mice and rats by replacing these animal models with tiny aquatic flatworms known as freshwater planarians.

Tracking the genetic arms race between humans and mosquitoes
Every time you put on bug spray this summer, you're launching a strike in the ongoing war between humans and mosquitoes -- one that is rapidly driving the evolution of the pests.
More Pesticides Current Events and Pesticides News Articles

© 2015 BrightSurf.com