President Barack Obama survived a tough reelection battle this year—but scientists say an ancient lizard named for him met a far crueler fate. When a
10-kilometer-wide asteroid struck Earth 65 million years ago, killing off the dinosaurs, scientists thought that lizards, snakes, and other so-called
squamates mostly survived the impact. But a new study shows that more than 80% of squamates also died in the mass extinction, including one that
researchers christened Obamadon gracilis (center). The tiny animal with tall teeth, whose second name means slender, was discovered in
ancient rocks in Montana about a year ago. Mammals' evolutionary explosion, which began within 1.5 million years after the impact, is well documented, but
it turns out that the squamates had their own postimpact evolutionary bounce. By
comparing hundreds of species of lizards and their kin before and after the impact, the team uncovered both the squamates' mass extinction and the rise of
new species of squamates about 10 million to 15 million years later. That group gave rise to the ancestors of modern snakes and lizards, the researchers
report online this week in the Proceedings of the National Academy of Sciences. But poor Obamadon remains a relic of ancient history.
See more ScienceShots.
)
)
)
)
)
)
)
)
)
)
)
)
