[http://www.cpanel.ebar.com/news/article.php?sec=news&article=6259]
Size matters.
And it's the hot topic heating up climate change, especially with the publication of biologist Rae Goodman's study that challenges popular scientific belief that species get smaller as the climate warms.
Goodman's research findings that show a variety of species of birds habituating or migrating through the Bay Area are getting bigger has puzzled and surprised scientists, especially the researchers that discovered the anomaly.
"Completely surprised, there were a couple of other studies about birds getting smaller and I was stunned when that wasn't what I found," said Goodman, who made the discovery with four colleagues while a graduate biology student at San Francisco State University.
The students stumbled upon the discovery as a part of their master's degree project in biology under SFSU Professor Gretchen LeBuhn. The students examined bird weight and wing length that spanned 40 and 27 years gathered from thousands of birds and hundreds of different resident and migratory bird species around the San Francisco Bay Area. The information was gathered and stored at PRBO Conservation Science and the San Francisco Bay Bird Observatory, and the Coyote Creek Field Station. They also studied the birds' behavior patterns.
Goodman's article, "Avian body size changes and climate change: warming or increasing variability?" about the students' findings, was recently published in the journal Global Change Biology .
Goodman, a 29-year old queer woman, graduated a year ago and is now teaching high school biology at the San Francisco's Jewish Community High School of the Bay.
Weird science -
Nat Seavy, research director of Pacific Coast and Central Valley Group of PRBO Conservation Science, and Jill Bluso Demers, executive director of San Francisco Bay Bird Observatory, who worked with Goodman and her colleagues, were equally surprised by the discovery.
The breadth and variety of the data examined by Goodman and her colleagues made climate change the most "parsimonious explanation," said Bluso Demers, who pointed out that there haven't been many studies about birds' response to climate change conducted on the West Coast, especially the kind that Goodman did.
"The fact that she found this among all the birds that she looked at is really astounding to me," said Bluso Demers, who was especially surprised by the findings "considering that everywhere else that this has been looked at we, the scientific community, have been seeing declines in avian body size."
In many parts of the world species in warmer climates are getting smaller in response to climate change, which is in line with Bergmann's rule, said scientists.
German biologist Karl Bergmann's nearly 165-year-old rule claims body size tends to decrease as the climate warms. Contrary to the rule, Goodman's team found that it was more of an assumption that wasn't universal.
Bergmann's rule hasn't been "shown" before, Goodman said, in spite of more than a century and a half of scientific acceptance.
Bergmann's rule "assumed" that size had to do with "warmer temperatures," said Goodman. "So part of what this study says is maybe the temperature isn't the thing or the only thing that is making this pattern happen."
Something else is happening in the San Francisco Bay Area; birds are actually increasing in size.
"The West Coast is responding to climate change differently than the rest of the world," said Bluso Demers.
Goodman believes something other than temperature is contributing to climate change and her study provides the first glimpse at that possibility.
Seavy agreed that the results suggest that there is "no one-size-fits-all explanation" for the affects of climate change.
Bluso Demers and Seavy suggested two explanations for the divergence from Bergmann's rule. Warmer temperatures promote food growth, and with the abundance of food so goes the size of birds. Additionally with more extreme weather, such as storms, birds are adapting to survive, the scientists said.
Bluso Demers added that "possibly the climate is becoming more variable," which concerns her.
"It's concerning that birds are changing in different ways around the globe," said Bluso Demers.
Uniform change would be easier to manage, she continued, but the "varied changes globally" in a variety of habitats – ocean to forest – and species – animals to plants – "makes managing for climate change even more challenging."
LeBuhn, who is traveling in Nepal, did not respond to a request for comment by press time.
Science bug -
"I've always been interested in science and species in the wild," said Goodman about her interest in biology. Recently she returned home to Northbrook, a suburb of Chicago, where she was raised in a reform Jewish congregation that was politically and socially active, she said.
While home, Goodman's mother pulled out one of her fifth grade science projects and she visited some of her elementary school teachers. She credits her primary teachers as her examples for learning how to teach students to question, work with information, discover their own answers to their questions, and how to work together as a group, she said.
Most important, her primary teachers taught her "how to get students interested in science and make it fascinating," said Goodman, who loves her job.
Goodman moved to Southern California originally to earn her undergraduate degree at Pomona College. She then followed her college roommate to San Francisco, which she now calls home.
Future climate -
"There are some big changes going on and we are working to figure out what's going on before it gets too bad," said Goodman.
Many scientific institutions around the world are currently examining body size in relation to climate change right now, said Goodman. Scientists are also looking at historical evidence going back to the Paleolithic period to compare current climate change patterns with other periods where the earth's climate was known to change.
"Climate change over the whole course of earth's history has gone along with mass extinction," said Goodman.
The effects of climate change happening right now could be reversed if scientists are armed with information that can be mined from existing databases, she said. It's a huge advantage to scientists fighting against global warming.
"One of the advantages of this type of research is a lot of it exists in existing data" and is "available for a lot of these studies right now," said Goodman, who pointed out that answers could be revealed within a "handful of years" if people focus on tapping into the existing data. "It's just a matter of how fast scientists get to [the information]."
Seavy agreed, telling the Bay Area Reporter that "all of the evidence points to greenhouse gas emissions," but aside from reducing the emissions, people need to "change our management and conservation practices to make sure that they are robust to the climate change that is going to happen."
Bluso Demers stressed the importance of continuing to monitor the environment.
"You have to monitor because you don't know what the conservation issues in the next 30 years will be," she said, pointing out that having the data will continue to help people "make informed decisions on our most precious resources."
"I really urge all of our policymakers to act quickly on climate change," said Bluso Demers.
Goodman is excited that she's been able to add to the "big picture of climate change" in a significant way with her discovery. The science is "very current science," she said.
It's not just a theory, but it's "capturing that change as it happens," and "also changing and adding to what we understood about climate change," Goodman said.
"To me it's exciting and fascinating. It's great to really feel like I'm adding something substantial to scientific knowledge," said Goodman.
Champion of Life
Biologist Rae Goodman (Photo: Courtesy SF State University)
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