Alligator fat can be made into biodiesel (and, yes, they have a lot of fat). Extreme cavers descend into the dark and dangerous depths of Earth's deepest cave. And we tour the original, long-lost SeaWorld that never was. It's time for the week's Landscape Reads!

Mapping the Deepest Cave on Earth

Exploring the deepest cave in the world is "a kind of Everest expedition turned upside down," writes Burkhard Bilger. Except there is no map, and nobody knows where they're going. Bilger follows a handful of extreme cavers into Mexico's Chevé system, where they squeeze through fissues and dive through underwater passages in the world's deepest spot. [The New Yorker]

The City as Ecosystem, the Chain-Link Fence as Habitat

In this essay for Design Observer, Peter Del Tredici writes powerfully about cities as distinct ecosystems. "The chain-link fence is one of the more specialized habitats of the urban environment. They provide plants — especially vines — with a convenient trellis to spread out on and a measure of protection from the predation of maintenance crews. Chain-link fences also provide "safe sites" for the germination of seeds, a manifestation of which are the straight lines of spontaneous urban trees that one commonly finds in cities, long after the fence that protected the trees is gone." [Design Observer]

Making Biodiesel from Leftover Alligator Fat

Who knew that there is so much alligator fat lying around? When researchers at the University of Louisiana began investigating a process of turning animal fats to biodiesel, people started sending them 50-pound chunks of alligator fat. Someday, the leftover fat from alligators and other dead animals sent to render facility could become the biodiesel that powers engines. [New York Times]

The Weird, Wonderful Vision for the Original SeaWorld

In 1961, there was no Shamu and no orca show. But there was an even more probable plan to train penguins to march and dance on the back of pilot whale. Conor Friedersdorf, who first learned of SeaWorld's origins through a friend who is the grandson of its co-founder, has unearthed its improbable original vision, taking us through a virtual tower of an ocean theme park that never was. [The Atlantic]

Top image: a publicity shot for Marineland, an early aquatic amusement park in Santa Monica Bay that heavily influenced the original vision for SeaWorld. By some accounts, it had at one time the largest collection of marine creatures ever assembled.