Slashdot Mirror

← Back to Stories (view on slashdot.org)

Ancestor of All Placental Mammals Revealed

Posted by samzenpus on from the back-in-the-day dept.

sciencehabit writes "The ancestor of all placental mammals—the diverse lineage that includes almost all species of mammals living today, including humans—was a tiny, furry-tailed creature that evolved shortly after the dinosaurs disappeared, a new study suggests. The hypothetical creature, not found in the fossil record but inferred from it, probably was a tree-climbing, insect-eating mammal that weighed between 6 and 245 grams—somewhere between a small shrew and a mid-sized rat. It was furry, had a long tail, gave birth to a single young, and had a complex brain with a large lobe for interpreting smells and a corpus callosum, the bundle of nerve fibers that connects the left and right hemispheres of the brain. The period following the dinosaur die-offs could be considered a 'big bang' of mammalian diversification, with species representing as many as 10 major groups of placentals appearing within a 200,000-year interval."

6 of 123 comments (clear)

  1. Pics or it didn't happen by Anonymous Coward · · Score: 1, Funny

    Just sayin'.

  2. Re:More Info Please... by Anonymous Coward · · Score: 5, Funny

    Here's what may have happened to the little guy...

  3. i feel a disney movie by decora · · Score: 5, Funny

    The rough group of placentals from the wrong side of the tracks has a young placental who falls in love with a nice placental from the meadow.. but their parents disapprove...

  4. Typical Redneck Response by tdp252 · · Score: 2, Funny

    Damn them whacky scientists. Me and my girl didn't come out some squirrel's butthole !

  5. Re:No intermediate steps to prove! by Anonymous Coward · · Score: 0, Funny

    and others would have us believe always existed alongside Homo sexuals as well.

  6. JJ Abrams To Direct "Placenta Matriarch" by Freshly+Exhumed · · Score: 1, Funny

    1. Scientists describe new evolutionary theory to assembled dignitaries from across the universe
      2. Leading Anti-Evolutionist looks really pissed.
      3. Cut to scene of Anti-Evolutionist ships massing over a lush, green planet
      4. Lens flare
      5. Anti-Evolutionist soldiers shoot all sorts of ray gun zappers at the scientists below, shouting "Die, wasters of money!"
      6. Lens flare
      7. After wicked battle, scientists are rescued by Yoda-trained hero.
      8. Lens flare
      9. Leader of Anti-Evolutionist armies wails in frustration, shouting "That is NOT evidence!!!"
    10. Lens flare
    11. Anti-Evolutionist armies plot massive attack from Death Stars.
    12. Lens fare.
    13. Great place to end Part One so that everyone needs to see Part Two in a few years.

    --
    I deny that I have not avoided attaining the opposite of that which I do not want.