HS-LS2-6

Evaluate the claims, evidence, and reasoning that the complex interactions in ecosystems maintain relatively consistent numbers and types of organisms in stable conditions, but changing conditions may result in a new ecosystem.

  1. Animals

    Some Greenland polar bears are surviving with very little sea ice

    The ‘glacial mélange’ on which they’ve come to rely — a mix of ice, snow and slush — could be a temporary refuge for some polar bears.

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  2. Science & Society

    Explainer: What is an endangered species?

    Threats such as climate change and habitat loss can put species at risk of going extinct. Different words describe that risk.

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  3. Life

    In blazing heat, some plants open leaf pores — and risk death

    When heat waves and droughts collide, water is precious. Some thirsty plants try to cool off by opening tiny pores — only to lose water even faster.

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  4. Animals

    Rewilding returns lost species to strengthen ecosystems

    Restoring the missing species can help undo human-caused problems by aiding forests, slowing climate change and reducing wildfires.

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  5. Animals

    Explainer: What is an invasive species?

    These foreign organisms hitchhike, spread widely and stir up trouble in native ecosystems.

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  6. Ecosystems

    Cheatgrass thrives on the well-lit urban night scene

    Middle-grade campers team up with ecologists at Denver University to show that streetlights boost the growth of a reviled invasive species.

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  7. Animals

    Some pikas survive winter by eating yak poop

    Pikas endure bone-chilling cold on the Tibetan Plateau by using little energy and fueling up on yak poop.

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  8. Animals

    Spiders can take down and feast on surprisingly big snakes

    Snared in sticky webs and subdued by poison, even venomous snakes can become a spider’s soup.

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  9. Animals

    Urchin mobs can literally dis-arm a predator

    Urchins are important herbivores — but not strict vegetarians. When hungry enough, they may even rip apart their predators for lunch.

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  10. Climate

    Urchin takeover underlies California’s vanishing kelp forests

    Some 95 percent of kelp forests along its northern coast are gone. Meanwhile, sea otters are helping slow the loss of surviving kelp farther south.

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  11. Climate

    Changing climate now threatens northern lakes year round

    Lakes in northern climes are getting warmer, and that’s not good for people, plants or animals.

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  12. Health & Medicine

    Some microbial hitchhikers may weaken body’s attack on COVID-19

    New research identifies an altered mix of microbes in the body — ones commonly seen in people with poor diets — that may worsen coronavirus disease.

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