HS-LS4-2

Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential for a species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited resources, and (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.

  1. Fossils

    This dinosaur was no bigger than a hummingbird

    The skull of one of these ancient birds — the tiniest yet known — was discovered encased in a chunk of amber originally found in Myanmar.

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  2. Animals

    Analyze This: Shimmering colors may help beetles hide

    Delve into data showing how brilliant colors that shift as a viewer — or predator — moves may help iridescent insects blend in.

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  3. Health & Medicine

    Immune arms-race in bats may make their viruses deadly to people

    An overactive immune system may help bats avoid being sickened by many viruses. This may viruses becoming stronger — and deadlier — when they hit other species.

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  4. Health & Medicine

    The many challenges of corralling a coronavirus outbreak

    The Chinese government has quarantined millions of people in hopes of limiting spread of a new coronavirus. But no one yet knows how much this will help.

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  5. Health & Medicine

    Serious virus emerges in China and is spreading globally

    A new viral infection emerged in December 2019 among people in Wuhan, China. The mystery illness has already killed at least 17 people and sickened many hundreds.

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  6. 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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  7. 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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  8. Animals

    Blood vessels in their heads kept big dinos from overheating

    Giant dinosaurs evolved several ways to cool their blood and avoid heatstroke.

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  9. 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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  10. Genetics

    Explainer: What is epigenetics?

    Epigenetics is the study of molecular “switches” that turn genes on and off. Tweak those switches and there could be big health consequences.

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  11. 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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  12. Animals

    The turning of wolves into dogs may have occurred twice

    The process of turning wolves into dogs, called domestication, may have occurred twice — in the East and the West — ancient DNA suggest.

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