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. 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

    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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  4. 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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  5. 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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  6. 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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  7. 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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  8. Animals

    Cool Jobs: Pet science

    Pets make great subjects for research. These scientists work to make our animals — and us — healthier and happier.

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  9. Humans

    News Brief: Ancient teeth point to Neandertal relatives

    New analyses of some teeth found in Siberia indicate that Neandertal cousins known as Denisovans lived there for at least 60,000 years. That would have had them around the same place as modern humans — and at nearly the same time.

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  10. Health & Medicine

    Chikungunya wings its way north — on mosquitoes

    A mosquito-borne virus once found only in the tropics has adapted to survive in mosquitoes in cooler places, such as Europe and North America.

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  11. Genetics

    DNA: Our ancient ancestors had lots more

    Ancestral humans and their extinct relatives had much more DNA than do people today, a new study finds. It mapped genetic differences over time among 125 different human groups.

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  12. Animals

    Return of the bed bug

    Bed bugs have staged a comeback over the past 15 years. The bloodsucking parasites succeeded through a combination of evolution and luck.

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