Nature adapts to survive climate change
While the climate change discussion in Washington is moving at a glacial pace, nature is responding to climate change at record speed. The animal, plant and insect kingdoms aren’t interested in public policy. They don’t read political blogs. They adapt because they have to. They must change to survive.
We would be wise to heed the signs.
Animals, plants and even insects are now adapting quickly to shifts in temperatures, often by migrating to cooler climates, modifying their diets and altering breeding cycles.
This is happening at blinding speed in large, complex ecosystems. Throughout most of the 20th century, for example, tree range shift occurred at about 0.4 miles a year. Since 1990, however, climate changes have caused species range to move by an average of 12 miles a year. A 2009 U.S. Forest Service study, tracking 40 major tree species in 30 Eastern states, concluded that tree ranges had moved, on average, more than 60 miles north in less than a century.
More than 60 percent of the birds the National Wildlife Federation tracked in a recent study have expanded their range northward by an average of 35 miles in the last 40 years. Fourteen small mammal species in the Sierra Nevada Mountains were found to have extended the elevation at which they can survive by an average of 1,640 feet.
This rapid adaptation is occurring around the world. British researchers recently analyzed more than 2,000 animal and plant species in Britain and found that many had already made significant adaptations to a changing environment.
The Comma butterfly, for example, has migrated north from central England to Edinburgh, Scotland – a distance of more than 130 miles – over the past 40 years. They found that the Cetti warbler, a small bird, has moved more than 90 miles north.
Changes are also evident in breeding cycles. New storm patterns brought on by climate change have affected when tropical tree frogs lay their eggs, the Smithsonian Tropical Research Institute has found.
The climate may now be changing so quickly that some species do not have time to adapt. With the Antarctic warming, for example, penguins now need to lay their eggs far earlier, according to research at Stony Brook University in New York. Yet of the three species studied – the Adelie, Chinstrap and Gentoo – only the Gentoo has been able to adapt quickly. As a result, that population has exploded, while the other two are dwindling.
In another study, researchers at Stellenbosch University in South Africa a few years ago began exploring how small animals on a remote sub-Antarctic island adapted to climate change. Their original hypothesis: Classic evolution would ensure that the species survived. The biologists found, however, that several species did not evolve.
The rate of ecosystem change was so great, the scientists concluded, that some animals’ adaptive response mechanisms could not keep pace. They simply never kicked in.
When plants and animals move, adapt or die off, the planet’s biodiversity diminishes. This is a big deal. The loss of biodiversity affects the environment as much as climate change and pollution do, according to a recent National Science Foundation study conducted by the National Center for Ecological Analysis and Synthesis.
Human health is directly linked to, and correlated with, a healthy, diverse ecosystem. For example, when coral reefs die, fish die. About 75 percent of the world’s fish catch is used for human consumption. No fish, no food.
We use the natural ecosystem for food, fresh water, medicines, clothing and much more. A report for the 2013 National Climate Assessment concluded that the extensive changes in these ecosystems will have important implications for future human activity, including what we eat and how we live.
Media coverage of climate change usually focuses on the dramatic effects of the natural disasters generated, or exacerbated, by these changing ecosystems. The droughts in the Midwest, hurricane Sandy and the relative absence of snow are all easy to understand, and their impact on human life is immediate and visible.
Our tendency to downplay the less visible, but more fundamental, clues – like the changes occurring in the animal kingdom – is understandable. But misguided. Think of these as early warning signs of the potentially profound changes to come if we do not act soon. If global temperatures increase more than two to three degrees Fahrenheit above current levels, according to the U.N.’s Intergovernmental Panel on Climate Change, up to one-third of the species on Earth could be at risk of extinction.
That could include us.
The natural world is acting on climate change, even if Washington isn’t. We need to start paying attention.
PHOTO (TOP): The population of Adelie penguins has been dwindling due to climate change. Here, Adelie penguins are making their way to the water in the Cape Evans region of
Antarctica, February 2002. REUTERS/Mark Baker
PHOTO (Insert A): The Eastern Comma butterfly in an undated image. A female is on the left, a male at right. REUTERS/Canadian Biodiversity Information Facility.
PHOTO (Insert B): A Chinstrap Pengiun on Half Moon Island in the South Shetlands, off the Antarctic peninsula. This is one penguin species proving unable to adapt to the rapidly changing environment. REUTERS/Archive
PHOTO (Insert C): Unaffected corals in Dibba, October 18, 2004, before the 2008 Red Tide which badly affected life underwater and killed many fish. Coral reefs support a third of the Gulf’s fish populations. REUTERS/Climate change/Handout