If human evolution had favored tree-walking over ground-strolling, commuters would swing hand over hand across skyscraper branches and grabbing morning coffee would be a far more dangerous affair. Make like a monkey with today’s Groupon: for $20, you get admission to the Treetop Challenge, a 90-minute zipline obstacle course that's one of the Treetop Trek Aerial Adventures located at Brevard Zoo in Melbourne (a $40 value). Treetop Trek tickets do not include or require zoo admission.

The longest and most obstacle-laden of the three Treetop Trek courses, the Treetop Challenge whisks vest-protected venturers down a zipline-transit system of more than 700 feet that hangs 40 feet above the wetlands and along the north side of the La Selva exhibits at the Brevard Zoo. As nimble limbs clamber across the crab walks and jungle bridges, watchful eyes may be rewarded with glimpses of some of La Selva's monkeys, tropical birds, and giant anteaters on their own treetop obstacle course. After tree-hoppers complete the 20-foot-high challenges, they segue to higher ground, doubling their previous height to negotiate the zipline highways strung above wetlands where alligators lurk subsurface, poking their eyes out of the water to gaze enviously at the opposable thumbs of fliers-by.