Monkeys Are Made of Chocolate

by Jack Ewing

If you are thinking about a visit to Costa Rica and plan on doing a lot of hiking in the jungle while you’re here, there are several simple measures you can take to minimize the risk of snakebite: (1) look in your boots before you put them on, (2) look before you step, and (3) buy a lottery ticket. Why buy a lottery ticket? Because in the short time you are in Costa Rica, you will have a better chance of winning the lottery jackpot than you will of getting bitten by a poisonous snake.

Eight million years ago, when geological forces were forming Central America, the first South American mammals to set foot on the isthmus were two species of ground sloth that had to swim over 60 kilometers (37 miles) of treacherous ocean to reach the new land. They won the race five million years ahead of four other species of sloths and many other mammals that arrived later.

Red mangrove (Rhizophora mangle), the most common species, seldom exceeds 10 meters (33 feet) in height, grows in several meters of water most of the year and has as much branching in its underwater roots as in the crown.

Barnacles, sponges, coral and oysters colonize the roots and are fed upon by the fish, clams, shrimp, crabs and lobsters that thrive in the water amongst the tangled mass of mangrove roots. The bottom of the estuary is an organic soup, a thick mixture of silt, decaying vegetable matter and bird guano that supports a wide spectrum of microorganisms which play an important and little-understood role in the complex realm of mangrove ecology.

Black mangrove (Avicena bicolor) thrives in the mud at water’s edge and is known for the pencil-like, air-breathing roots that sprout up like an extremely coarse shag rug, covering the surface around the base of the tree. The thick trunks and branches are often hollow and provide shelter and nesting nooks for wildlife.

One denizen of this captivating environment, the mangrove tree crab (Aratus pisonii), is of particular interest. It lives in the tops of mangrove trees, especially red mangrove, and eats mangrove leaves and large insects. Flocks of several types of egrets and herons descend into the tops of trees to prey on these small crustaceans, thus creating general panic. Some of the fleeing crabs run down the trunk, but others leap from tree to tree, and many fall into the water, only to be gobbled up by the waiting jaws of hungry fish. A general feeding frenzy ensues for both birds and fish.

Local fishermen refer to this phenomenon as a garzeria, derived from the word garza, the local name for the egrets and herons that start the commotion.

According to noted biologist Edward O. Wilson, in his landmark work, The Diversity of Life: “Our species appropriates between twenty and forty percent of the solar energy captured in organic material by land plants.”

“Underlying all ecological science is the inevitable fact that, given a chance, the earth will eventually restore itself. The salient question we need to discuss in our communities and businesses is whether humankind will participate in that restoration or be condemned by our ignorance to vanish from the planet.”