Here kitty . . . just kidding. Today’s fossil fuel, the North American Lion (panthera leo atrox) was an extinct version of the modern-day King of the Jungle. These dudes were truly Big Cats, some 25-percent larger than today’s version, up 8 feet in length and weighing upwards of 700 pounds. Yep, 700 pounds of body weight equals a lot of fresh wildebeest every day---and antelope, and deer, and bison, and other herbivorous critters that also roamed these parts in abundance. Fossils of these guys have been found all over the North American continent from the Yukon to Mexico, where they lived during the Pleistocene Era before becoming extinct around approximately 10,000 BC. Hunting by humans may have led to their demise, as lion bones have been found in Paleolithic human-waste sites. (Mmmm, spit-roasted lion. Does that sound good, or what? Then again, considering the protein-rich diet these dudes enjoyed, we'd reckon each of of 'em would be equal to 700 pounds of highest-octane Top Fuel--and heck, that's a lot of quarter-miles in our book.)