Dating en panama

23 Oct

It is not so unusual for plants to cross where animals dare not tread. The famous 19th-century naturalist Alfred Russel Wallace discovered that animals do not cross the strait separating Bali and Lombok, as if observing an invisible line. A geologist's revisionist theory pushing the formation of the Isthmus of Panama back 10 million years casts doubt on mainstream ideas of what caused the last ice age as well as the global glaciation cycle that generates the world's current climate A few years ago geologist Carlos Jaramillo stood in a man-made canyon in Panama staring at rocks he knew to be 20 million years old, and shook his head in confusion.According to conventional geologic theory, the Panamanian Isthmus didn't emerge from the sea until just a few million years ago.Jaramillo's team aims to gain more insight into these subtleties in the next two years, as Canal Zone excavations continue. But they have a longer lens in mind as well: They have been setting aside hundreds of rock samples in hopes that future scientists can study them with yet-to-be-developed geologic dating methods. 2012 Evidence for middle Eocene and younger emergence in Central Panama: implications for Isthmus closure. But at shallower depths currents abruptly hit a wall. 2011 Fracturing of the Panamanian Isthmus during initial collision with South America.The surprise finding: at less than 50 meters currents arise that have never before been simulated. W., Jaramillo, C., Bayona, G., Restrepo-Moreno, S., Montes, C., Cardona, A., Mora, A., Speakman, R. Katie Worth is a science writer based in Santiago, Chile.

dating en panama-2dating en panama-83dating en panama-72

Flora and fauna began traipsing between the two American continents, often extinguishing each other.After all, it could be decades before geologists have another chance to delve physically into Panama's ancient history, Jaramillo says. "Most of the rocks we have seen in the past three years have already gone," Jaramillo says. "Some entire mountains that we used to collect from two years ago are now 50 meters below water. So we know we're in a race against time." Publication references Montes, C., Cardona, A., Mac Fadden, R., Moron, S.