Posts tagged behaviors
Climate change: Big changes for big mammals
Jan 23rd
in mammal responses to climate change
If you were a shrew snuffling around a North American forest, you would be 27 times less likely to respond to climate change than if you were a moose grazing nearby.
That is just one of the findings of a new University of Colorado Boulder assessment led by Assistant Professor Christy McCain that looked at more than 1,000 different scientific studies on North American mammal responses to human-caused climate change. The CU-Boulder team eventually selected 140 scientific papers containing population responses from 73 North American mammal species for their analysis.
The studies assessed by the team examined seven different responses to climate change by individual mammal species: local extinctions of species known as extirpations, range contractions, range shifts, changes in abundance, seasonal responses, body size and genetic diversity. The researchers used statistical models to uncover whether the responses of the 73 mammals to a changing climate were related to aspects of their physiology and behavior or the location of the study population.
The analysis showed only 52 percent of the mammal species responded as expected to climate change, while 7 percent responded the opposite of expectations and the remaining 41 percent had no detectable response. The two main traits tied to climate change responses in the CU-Boulder study were large mammal body size and restricted times during a 24-hour day when particular mammal species are active, she said.
A paper on the study by McCain and former CU-Boulder postdoctoral fellow Sarah King was published online Jan. 22 in the journal Global Change Biology. The National Science Foundation funded the study. King is currently a research associate at Colorado State University.
While body size was by far the best predictor for response to climate change — almost all of the largest mammals responded negatively — the new study also showed that mammals active only during the day or only at night were twice as likely to respond to climate change as mammals that had flexible activity times, she said.
“This is the first time anyone has identified specific traits that tell us which mammals are responding to climate change and which are not,” said McCain of CU-Boulder’s ecology and evolutionary biology department.
McCain said she and King were surprised by some of the findings. “Overall the study suggests our large, charismatic fauna — animals like foxes, elk, reindeer and bighorn sheep — may be at more risk from climate change,” she said. “The thinking that all animals will respond similarly and uniformly to temperature change is clearly not the case.”
The researchers also found that species with higher latitudinal and elevation ranges, like polar bears, American pikas and shadow chipmunks, were more likely to respond to climate change than mammals living lower in latitude and elevation. The ability of mammals to hibernate, burrow and nest was not a good predictor of whether a species responded to climate change or not. American pikas have been extirpated from some of their previously occupied sites in the West, as have shadow chipmunks, which are in decline in California’s Yosemite National Park.
One of the most intriguing study findings was that some small mammals may shelter from climate change by using a wider array of “micro-climates” available in the vegetation and soil, she said. McCain compared the findings with the events at the K-T boundary 66 million years ago when an asteroid smacked Earth, drastically changing the climate and killing off the big dinosaurs but sparing many of the small mammals that found suitable shelter underground to protect them from the cataclysmic event.
“I think the most fascinating thing about our study is that there may be certain traits like body size and activity behaviors that allow some smaller mammals to expand the range of temperature and humidity available to them,” said McCain, also a curator of vertebrate zoology at the University of Colorado Museum of Natural History. “These areas and conditions are not available to bigger mammals that live above the vegetation and experience only ambient temperatures.”
The new study builds on a growing body of global information documenting the shifting behaviors and environments of organisms like flowers, butterflies and birds in response to a warming world, said McCain.
“If we can determine which mammals are responding to climate change and the ones that are at risk of disappearing, then we can tailor conservation efforts more toward those individual species,” said McCain. “Hopefully, this potential loss or decline of our national iconic mammals will spur more people to curb climate impacts by reducing overuse of fossil fuels.”
For more information on the ecology and evolutionary biology department visit http://ebio.colorado.edu. For more information on the University of Colorado Museum of Natural History visit http://cumuseum-archive.colorado.edu/About/directory.html.
CU: study links autism symptons to gut germs
Dec 19th
gut microbes called ‘groundbreaking’
in CU-Boulder-authored journal article
A new study showing that feeding mice a beneficial type of bacteria can ameliorate autism-like symptoms is “groundbreaking,” according to University of Colorado Boulder Professor Rob Knight, who co-authored a commentary piece about the research appearing in the current issue of the journal Cell.
The autism study, published today in the same issue of Cell, strengthens the recent scientific understanding that the microbes that live in your gut may affect what goes on in your brain. It is also the first to show that a specific probiotic may be capable of reversing autism-like behaviors in mice.
“The broader potential of this research is obviously an analogous probiotic that could treat subsets of individuals with autism spectrum disorder,” wrote the commentary authors, who also included CU-Boulder Research Associate Dorota Porazinska and doctoral student Sophie Weiss.
The study underscores the importance of the work being undertaken by the newly formed Autism Microbiome Consortium, which includes Knight as well as commentary co-authors Jack Gilbert of the University of Chicago and Rosa Krajmalnik-Brown of Arizona State University. The interdisciplinary consortium—which taps experts in a range of disciplines from psychology to epidemiology—is investigating the autism-gut microbiome link.
For the new Cell study, led by Elaine Hsiao of the California Institute of Technology, the researchers used a technique called maternal immune activation in pregnant mice to induce autism-like behavior and neurology in their offspring. The researchers found that the gut microbial community of the offspring differed markedly compared with a control group of mice. When the mice with autism-like symptoms were fed Bacteriodes fragilis, a microbe known to bolster the immune system, the aberrant behaviors were reduced.
Scientific evidence is mounting that the trillions of microbes that call the human body home can influence our gut-linked health, affecting our risk of obesity, diabetes and colon cancer, for example. But more recently, researchers are discovering that gut microbes also may affect neurology—possibly impacting a person’s cognition, emotions and mental health, said Knight, also a Howard Hughes Medical Institute Early Career Scientist and an investigator at CU-Boulder’s BioFrontiers Institute.
The Autism Microbiome Consortium hopes to broaden this understanding by further studying the microbial community of autistic people, who tend to suffer from more gastrointestinal problems than the general public.
People with autism spectrum disorder who would like to have their gut microbes sequenced can do so now through the American Gut Project, a crowdfunded research effort led by Knight.
The consortium also includes Catherine Lozupone and Kimberly Johnson of CU-Boulder, James Adams of Arizona State University, Mady Hornig of Columbia University, Sarkis Mazmanian of the California Institute of Technology, John Alverdy of the University of Chicago and Janet Jansson of Lawrence Berkeley Lab.
For more information on the American Gut Project visit http://americangut.org.
-CU-
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Robert Reich Interview – Boulder Denver New Tech Meetup
Feb 20th
Jann Scott Interviews Boulder-Denver New Tech Meetup founder Robert Reich and we learn about Robert has created a great place for New Tech companies in Colorado to meet and share their ideas and become apart of the growing community of multimedia in the area and what it means to be a Start Up company and a Small Business.