1. Paleontology

    Northern Extinction: Alaskan horses shrank, then disappeared

    Horses that lived in Alaska shrank dramatically in body size before they went extinct at the end of the last ice age.

  2. Paleontology

    Ancient atmosphere was productive

    New laboratory experiments suggest that extra carbon dioxide in the atmosphere in the era just before the dinosaurs went extinct may have boosted plant productivity to at least three times that found in today’s ecosystems.

  3. Paleontology

    Healed scars tag T. rex as predator

    Healed wounds on the fossil skull of a Triceratops—wounds that match the size and shape of those that would be made by Tyrannosaurus rex—are a strong sign that the tooth scrapes are a result of attempted predation, not scavenging.

  4. Paleontology

    Role of gastroliths in digestion questioned

    New analyses of the gastroliths in ostriches are casting doubt on the theory that large, plant-eating dinosaurs swallowed stones to grind up tough vegetation and thereby aid their digestion.

  5. Paleontology

    Tracks suggest chase, capture, and after-meal respite

    A 1.3-meter-long, S-shaped trail of fossil footprints discovered in southwestern Indiana includes one set of disappearing tracks—suggesting an ancient chase—and an impression where the predator rested after its meal.

  6. Paleontology

    Bob, Bob, Bobbin’ Along: Dinosaur buoyancy may explain odd tracks

    New lab experiments and computer analyses may explain how some of the heftiest four-legged dinosaurs ever to walk on Earth could have left trackways that include the imprints of only their front feet.

  7. Paleontology

    Fossils of Flyers: Bones tell why Atlantic albatross disappeared

    Ancient albatross fossils suggest that rising sea levels 400,000 years ago wiped out the North Atlantic population of short-tailed albatross.

  8. Paleontology

    Reptile remains fill in fossil record

    The fossil remains of a sphenodontian, an ancient, lizardlike reptile, are helping fill a 120-million-year-old gap between this creature's ancestors and today's tuatara, sole survivors of the once prominent group.

  9. Paleontology

    Some trilobites grew their own eyeshades

    The 380-million-year-old fossil of a trilobite strongly suggests that members of at least some trilobite species were active during the daytime, a lifestyle that scientists previously had only suspected.

  10. Paleontology

    Ratzilla: Extinct rodent was big, really big

    Scientists who've analyzed the fossilized remains of an extinct South American rodent say that the creatures grew to weigh a whopping 700 kilograms.

  11. Paleontology

    Fossils’ ear design hints at aquatic lifestyle

    New studies of distinctive skull structures in fossils of one of Earth's earliest-known four-limbed creatures suggest the animal could hear best when it was underwater.

  12. Paleontology

    Oh, what a sticky web they wove

    A look inside a piece of 130-million-year-old amber has revealed a thin filament of spider silk with sticky droplets that look just like those produced by modern spiders.