They're called tepuis, and they may just be the missing link to our past. Huge tabletop mountains that are as evolutionarily isolated as the Galapagos Islands, these mysterious plateaus sit in the midst of South America, spanning Venezuela, Brazil, and Guyana. Being so remote, they have yet to be explored by many scientists; but one seventy-one year old biologist in particular decided to go on a mission to learn more about this curious region and the species it's hiding.
To get there, Dr. Bruce Means and his team were dropped on the top of one of the tapuis in Guyana by helicopter and had to wait two days until the rain cleared to be able to begin their work. But that was the easy part. Dr. Means wasn't just interested in the ecosystem on the top of the tapui - he wanted to know what lay in the ravines between tapuis; and more specifically, if there was a difference in closely-related species that lived on the top of the rapuis and in between them. His focus was a particular frog species, called the pebble frogs. But in order to get to them, he had to descend his first rappel ever, free-hanging from a 1,000 meter tapui over a sinkhole. No big deal.
But, he says, it was worth it, because what he found was incredible. Dr. Means was able to find enough species of the ravine pebble frog to collect data that could help scientists determine how long ago the species on the tops of the tapuis became isolated from those in between the tapuis. The greater significance of that discovery means understanding just how old these geologic structures are. Dr. Means is guessing that number to be from 40-50 millions of years old. Not bad, all from a little frog, eh?
