QA #2

Q Are birds really dinosaurs?

A Yes, but first, play the following video for some very relevant music:

Now, where were we. Ah, yes, are birds dinosaurs. Yes. Birds are avian dinosaurs (as opposed to non-avian dinosaurs, which refers to all dinosaurs except birds) that are derived (evolved) from theropods (dinosaurs that walked on two legs and had lizard-like–and, later, bird-like– pelvises). While there are a few paleontologists who would dispute this fact (i.e. some believe that birds are more related to mammals than to dinosaurs), the fossil evidence for the dino-bird connection is indubitable (I love that word!). One fossil in particular, Archaeopteryx (pronounced AR-kay-OPT-er-iX), is a shining example of what we-in-the-trade call a ‘transitionary,’ or ‘missing link’ fossil.

Photo 1: Archaeopteryx fossil from Germany.
Average length during life: around 1.5 feet.

First discovered in Germany in the 1800’s, Archaeopteryx lived during the late Jurassic period (around 145-150 millions years ago) and shares many similarities with theropods (see theropod description above). John H. Ostrom – a now-deceased paleontologist – described hundreds of these similarities by comparing the skulls and skeletons of Archaeopteryx with those of the feathered theropod dinosaur Deinonychus (pronounced DIE-no-NYE-kus) in a 1976 paper.

Photo 2: Deinonychus fossil.
Average length during life: around 11 feet.

Similarities between Archaeopteryx and Deinonychus include three-toed feet, sharp-toothed jaws, wishbones, and a long, bony tail. Archaeopteryx also bore claws on its very-reduced forelimb fingers – something no bird alive today can boast. On the flip side, there have been quite a few theropod fossils discovered that have bird-like characteristics, the most notable being feathers; the first dinosaur fossil found with feathers (or feather impressions, to be exact) is that of Sinosauropteryx (pronounced SIGN-o-sar-OPT-er-ix).

Photo 3: Sinosaurpteryx fossil from China.

This 140 million-year-old dinosaur, which measures in at less than half a foot tall and about two feet long, was discovered in the 1990’s in China’s Liaoning province (an unusually fossil-rich region) by full-time farmer part-time fossil hunter Li Yinfang. As you might be able to tell from its picture, Sinosauropteryx was endowed with small yet entirely respectable feathers: sweet! Now, between Archaeopteryx, Deinonychus, and Sinosauropteryx, I hope you're starting to see why birds are considered dinosaurs by 99% of paleontologists.

Anyhow, there you have it, folks. While there are a million more words to be said about the birds-are-dinosaurs topic, I think I’ll let you digest the small morsels given above. You can also now relish in the fact that the next time someone points at a bird and says “I think I read somewhere that birds are dinosaurs,” you’ll be able to say “yes, that’s 100% correct. Birds are non-avian dinosaurs derived from theropods,” to which they’ll probably reply “oh, snap!”

Next up: QA #3 How much lava, exactly, erupts from an exploding volcano? Is there much variability?

Later gators!

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