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Rising temperatures and seas,
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massive droughts,
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changing landscapes.
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Successfully adapting to climate change is growing increasingly important.
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For humans, this means using our technological advancement
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to find solutions,
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like smarter cities and better water management.
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But for some plants and animals,
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adapting to these global changes involves the most ancient solution of all:
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evolution.
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Evolutionary adaptation usually occurs along time scales of thousands
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to hundreds of thousands of years.
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But in cases where species are under especially strong selective conditions,
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like those caused by rapidly changing climates,
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adaptive evolution can happen more quickly.
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In recent decades,
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we've seen many plants,
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animals,
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and insects relocating themselves
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and undergoing changes to their body sizes,
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and the dates they flower or breed.
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But many of these are plastic,
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or nonheritable changes to an individual's physical traits.
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And there are limits to how much an organism can change its own physiology
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to meet environmental requirements.
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That's why scientists are seeking examples of evolutionary changes
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coded in species' DNA that are heritable,
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long-lasting,
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and may provide a key to their future.
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Take the tawny owl.
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If you were walking through a wintry forest in northern Europe 30 years ago,
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chances are you'd have heard, rather than seen,
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this elusive bird.
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Against the snowy backdrop,
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its plumage would have been near impossible to spot.
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Today, the landscape is vastly different.
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Since the 1980s,
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climate change has led to significantly less snowfall,
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but you'd still struggle to spot a tawny owl
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because nowadays, they're brown.
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The brown color variant is the genetically dominant form of plumage in this species,
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but historically,
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the recessive pale gray variant triumphed
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because of its selective advantage in helping these predators blend in.
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However, less snow cover reduces opportunities for camouflage,
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so lately, this gray color variant
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has been losing the battle against natural selection.
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The offspring of the brown color morphs, on the other hand,
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have an advantage in exposed forests,
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so brown tawny owls are flourishing today.
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Several other species have undergone
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similar climate-change-adaptive genetic changes in recent decades.
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Pitcher plant mosquitoes have rapidly evolved
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to take advantage of the warmer temperatures,
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entering dormancy later and later in the year.
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Two spot ladybug populations,
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once comprised of equal numbers of melanic and non-melanic morphs,
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have now shifted almost entirely to the non-melanic color combination.
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Scientists think that keeps them from overheating.
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Meanwhile, pink salmon have adapted to warmer waters
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by spawning earlier in the season to protect their sensitive eggs.
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And wild thyme plants in Europe are producing more repellent oils
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to protect themselves against the herbivores
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that become more common when it's warm.
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These plants and animals belong to a group of about 20 identified species
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with evolutionary adaptations to rapid climate change,
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including snapping turtles,
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wood frogs,
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knotweed,
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and silver spotted skipper butterflies.
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However, scientists hope to discover more species evolving
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in response to climate change out of 8.7 million species on the planet.
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For most of our planet's astounding and precious biodiversity,
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evolution won't be the answer.
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Instead, many of those species will have to rely on us
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to help them survive a changing world
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or face extinction.
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The good news is we already have the tools.
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Across the planet, we're making on-the-ground decisions
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that will help entire ecosystems adapt.
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Critical climate refuges are being identified and set aside,
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and projects are underway to help mobile species
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move to more suitable climates.
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Existing parks and protected areas are also doing climate change check-ups
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to help their wildlife cope.
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Fortunately, it's still within our power
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to preserve much of the wondrous biodiversity of this planet,
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which, after all, sustains us in so many ways.