1. Health & Medicine

    How much water should you drink a day? It depends on several factors.

    A study of more than 5,000 people in 23 countries finds that individual water need varies widely depending on physical and environmental factors.

  2. Space

    A proposed space telescope would use Earth’s atmosphere as a lens

    One astronomer has a bold solution to the high cost of building big telescopes.

  3. Health & Medicine

    Thick calluses don’t make feet any less sensitive

    Bare feet that develop thick calluses are just as sensitive as shoe-clad feet, a study in Kenya finds.

  4. Animals

    Nearly 200 Great Barrier Reef coral species also live in the deep sea

    There are more coral species lurking in the deep ocean that previously thought. That could be good news for their shallow water counterparts.

  5. Health & Medicine

    An eye disorder may have given Leonardo da Vinci an artistic edge

    An analysis of portraits believed to portray Leonardo da Vinci offers evidence that the artist had exotropia, in which one eye turns outward.

  6. Astronomy

    We may not have found aliens yet because we’ve barely begun looking

    A new calculation says SETI searches have combed the equivalent of a hot tub out of Earth’s oceans looking for extraterrestrial intelligence in space.

  7. Genetics

    A recount of human genes ups the number to at least 46,831

    A new estimate of the number of human genes adds in some RNA-producing genes.

  8. Life

    Inked mice hint at how tattoos persist in people

    Tattoos in mice may persist due to an immune response, challenging currently held beliefs about how the skin retains tattoos.

  9. Genetics

    Bones show Dolly’s arthritis was normal for a sheep her age

    Cloning didn’t cause the famous sheep to age prematurely.

  10. Animals

    3-D scans of fossils suggest new fish family tree

    Analysis of specimens from China implies ray-finned fishes evolved later than previously thought.

  11. Animals

    Fossil find suggests this ancient reptile lurked on land, not in the water

    An exquisitely preserved fossil shows that an ancient armored reptile called Eusaurosphargis dalsassoi wasn’t aquatic, as scientists had suspected.

  12. Animals

    Beetles have been mooching off insect colonies for millions of years

    The behavior, called social parasitism, has been going on for about 100 million years.