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.

More Stories in HS-LS4-2

  1. Animals

    Cool Jobs: Pet science

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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Fossils

    ‘Frankenstein’ dino showed a mashup of traits

    New species unearthed in Chile is “an anatomical Frankenstein,” declares one of its discoverers.

  7. Animals

    Orangutans take the low road

    Cameras spotted orangutans walking down logging roads to get around. That may be a good sign that they can adapt to changes in their woodsy environment.