Size and Weight:
The only prehistoric reptile ever to be named after a sitting president, Obamadon was a fairly unremarkable creature: a foot-long, insect-eating lizard that disappeared at the end of the Cretaceous period along with its dinosaur cousins. The announcement of Obamadon accompanied a paper reconsidering the fate of lizards and snakes during the K/T Extinction: it had previously been thought that most of these non-dinosaur reptiles escaped liquidation, but it turns out that as many as 80 percent of extant snake and lizard genera were killed off (the bigger ones faring worse than the smaller ones, presumably due to a lack of food).
With all the new dinosaurs being discovered around the world on a weekly basis, why name such a small, anonymous lizard after Barack Obama? No insult was intended, according to lead researcher Nicholas Longrich: this lizard's "type specimen" had been making the desultory rounds for a while (most paleontologists aren't as impressed by Cretaceous lizards and snakes as they are by contemporary dinosaurs), and Longrich happened to examine it in late 2008, after Obama had been elected president. "I said, yeah, we should name a dinosaur after him," Longrich recounted to MSNBC. "It was sort of a smart-ass comment." (As you might expect, lots of non-science-oriented news outlets have assumed that Obamadon is a dinosaur; most people are unaware that not every prehistoric lizard deserves this designation!)