Is Global Warming Making Birds Bigger? - As if we needed more reasons to cool it on the greenhouse gases, researchers in California are now hypothesizing that global warming could be causing the state's birds to grow significantly larger than they were even 25 years ago.
According to a study published in Global Change Biology, robins have grown by about an eighth of an inch in wing length and become about .2 ounces heavier in the last 25 to 40 years, the Los Angeles Times reports.
The study goes on to report that Californian birds overall have grown between 2 and 5 percent, theoretically in order to survive the severe storms brought on by global warming.
The theory has one major challenge: Bergmann's rule, an ecological principle, has long assumed that birds and mammals tend to be bigger at higher altitudes in order to combat chilly temps. According to that logic, if the world's birds were responding to rising temperatures they should be shrinking not bulking up.
Even so, the growing birds phenomenon certainly warrants further investigation. "The degree of physical change over a relatively short scale of time is remarkable and surprising," Jill Demers, executive director of the San Francisco Bay Bird Observatory, said in the article. "Similar studies in Pennsylvania and Europe, for example, show that birds there have decreased in size over the past several decades."
These birds aren't the first on the West Coast to exhibit some unorthodox behavior.
In Everett, Wa. last June, a flock of angry birds were spotted attacking the local police station, according to MSNBC.com.
In some Hitchcock-ian scenes, the crows dive-bombed police officers and sped from the sky to attack them in the parking lot. Eerier still: Crows can recognize and remember individual facial features.
The aggressive incidents were not linked to global warming; rather, the crows were defending their nearby nests from any perceived predators. ( yahoo.com )
According to a study published in Global Change Biology, robins have grown by about an eighth of an inch in wing length and become about .2 ounces heavier in the last 25 to 40 years, the Los Angeles Times reports.
The study goes on to report that Californian birds overall have grown between 2 and 5 percent, theoretically in order to survive the severe storms brought on by global warming.
The theory has one major challenge: Bergmann's rule, an ecological principle, has long assumed that birds and mammals tend to be bigger at higher altitudes in order to combat chilly temps. According to that logic, if the world's birds were responding to rising temperatures they should be shrinking not bulking up.
Even so, the growing birds phenomenon certainly warrants further investigation. "The degree of physical change over a relatively short scale of time is remarkable and surprising," Jill Demers, executive director of the San Francisco Bay Bird Observatory, said in the article. "Similar studies in Pennsylvania and Europe, for example, show that birds there have decreased in size over the past several decades."
These birds aren't the first on the West Coast to exhibit some unorthodox behavior.
In Everett, Wa. last June, a flock of angry birds were spotted attacking the local police station, according to MSNBC.com.
In some Hitchcock-ian scenes, the crows dive-bombed police officers and sped from the sky to attack them in the parking lot. Eerier still: Crows can recognize and remember individual facial features.
The aggressive incidents were not linked to global warming; rather, the crows were defending their nearby nests from any perceived predators. ( yahoo.com )
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