Butterflies help predict climate change


If Dr. Arthur Shapiro of UC Davis had $1 or even a penny for the steps of every hike he has taken in the past four decades, he might be one of the world's richest men. Then again -- maybe he already is.

"I'm out in the field 200 days a year. It's a good life," he said.

His commodities begin life as eggs and they blossom. There is little a butterfly does that Shapiro cannot explain.

He is the butterfly equivalent of a census taker. On this this day, he expected to find 11 different species along the American River in the Sierra Foothills, including the Pipevine Swallowtail.

"It's the commonest thing on the American River bikeway," Shapiro said.

Since Shapiro began his counting treks, some 40 years ago, suburbs have replaced wilderness in many places, and the butterflies have changed with them.

"As civilization spreads, natives withdraw and the weedy ones come in," he said.

But the natives are the ones Shapiro cares most about, because butterflies are what scientists call indicator species. They have relatively short lifespans and generations, which makes them perfect for studying the effects of climate change.

"I know climate is happening," Shapiro said. "That is another issue. I don't know the answer to that. And I am not sure anybody does," he added when asked if it was human induced.

Causes aside, Shapiro does know this however, that after all his years of collecting and cataloging of butterflies, the patterns are changing and fast, along with climate triggered timetables.

As the world warms, Shapiro has noted some species now appear as three weeks earlier than they did just three decades ago.

"Three weeks is enormous. I mean, what it does is tell us that the whole biosphere is potentially reacting to climate change," he said. Change is a constant and normal state of affairs, he argues. The absence of change would be abnormal.

So says the curious scientist with no political agenda, except finding the truth.

"No. We got eight. Eleven was just a guestimate, But truth rules. That's the nature of science," Shapiro said.

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