HS-LS4-4

Construct an explanation based on evidence for how natural selection leads to adaptation of populations.

  1. Microbes

    Globetrotting microbes in airplane sewage may spread antibiotic resistance

    Along with harder-to-kill microbes, airplane sewage contains a diverse set of the genes that let bacteria evade antibiotics.

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  2. Microbes

    Drug-resistant germs kill some 35,000 Americans each year

    The new mortality rate may be way low, some experts say. Also troubling are two new germs that have emerged as big and urgent threats.

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  3. Animals

    Why are bird eggs in cold climates darker colored?

    A global survey of bird egg color has revealed a simple trend: the colder the climate, the darker the egg.

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  4. Genetics

    What we can — and can’t — learn from our pets’ DNA

    Your dog or cat’s DNA is an open book. DNA tests tell people about their pet’s breed and attempt to predict things about its behavior and health.

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  5. Genetics

    DNA tells tale of how cats conquered the world

    Ancient DNA study suggests that domesticated cats spread across the ancient world in two waves.

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  6. Animals

    Animals can do ‘almost math’

    Humans aren’t the only animals with a number sense. Scientists are trying to figure out where and when it evolved.

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  7. Life

    Scientists watch germs evolve into superbugs

    To study how bacteria can evolve resistance to a wide variety of drugs, scientists spread the germs on a food-filled plate the size of a foosball table. Then, they watched resistance rise.

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  8. Life

    How a moth went to the dark side

    Peppered moths and some butterflies are icons of evolution. Now scientists have found a gene responsible for making them so.

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  9. Oceans

    Polar bears swim for days as sea ice retreats

    Melting sea ice is forcing polar bears to swim long distances — up to nine days in one case. Such long treks may be more than the bears can handle.

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  10. Humans

    Slicing meat may have aided human evolution

    An experiment with modern-day humans shows how slicing meat could have saved human ancestors energy — and let their bodies and brains get bigger.

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  11. Animals

    Mates or survival: Which explains a bird’s color?

    When male birds are brightly colored, we assume that’s because their plumage attracts the gals. But a new study with thousands of museum specimens shows that sometimes survival is just as important a factor behind bird color.

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  12. Animals

    Ocean animals have mushroomed in size

    ompared to a half-billion year ago, sea creatures are, on average, roughly 150 times bigger, a new study finds.

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