PANAMÁ SPECIAL
PERFIL
390,000 Grains of pollen to identify
I don’t waste time looting the brain of this researcher who generously received the Uninorte communications team after a morning of field demonstrations and tours of the Smithsonian collections. The first one that catches my attention is the pollen repository on the first floor. Neatly placed in red boxes like books in a library, there are thousands of microscope glass plates with pollen grains from around the world, but with an emphasis on the Americas. The amazing collection of grains and spores from 25,000 plant species was created over more than 40 years by Alan Graham, a retired professor at the University of Kent and now curator emeritus of the Missouri Botanical Garden. By collecting material from herbaria everywhere, Graham effectively assembled the largest collection of tropical pollen in the world. Each plate is accompanied in a file by a card with information about the plant species represented by pollen. One of Jaramillo’s crusades is to transcribe and digitize all that crucial information, so that researchers anywhere can consult it without having to physically travel to Panama, to look card by card. Pollens are very resistant and are always preserved in the fossil record. That is why they are among the best friends of the detectives of the past and present. “We use them to date rocks and know the age of sediments. In anthropology they can help us understand what ancient humans ate. The Drug Enforcement Administration, DEA, uses them to track the movement of illegal cargo across borders and learn where it originated,” the researcher explains, adding that his team is also literally photographing every grain of pollen, and adding that information to a database that is public and online. Carlos Jaramillo’s other crusade is even more daring. It is something like the palynological equivalent of climbing the Christopher Columbus peak in the Sierra Nevada: to make a complete description of each and every pollen that existed in and around Colombia during the Cretaceous period before and after the impact of the Chicxulub meteorite, 66 million years ago. The idea is to reconstruct the evolution of the tropical rainforest before and during the fateful impact that killed the dinosaurs. For the past 15 years he and his students have been collecting rock samples from 17 locations in the Americas, representing different periods of this window of time. From each of the 1300 rock samples, Jaramillo separated
58 Universidad del Nor te
Carlos Jaramillo is one of the world’s most renowned Colombian scientists.
300 grains of pollen. That is, in total, he has 390,000 individual grains of pollen to identify. “Since hardly anyone had done anything about it, many species are new, and so the work has been super slow,” he explains, showing stacks of index cards covering a long table in the middle of his office surrounded by high windows open to the surrounding forests. Each card has a meticulously crafted pencil drawing of a pollen grain, with descriptions of the species, and sometimes a photo with some microscopic detail, glued to the back with a clip. The kind of wonderful, exhaustive, handmade taxonomic work you saw on botanical expeditions of the past. “I look at each grain, I draw it, I compare it with another to see if it is the same, if it has the hair here or there, if it is round or elongated, smooth or with holes, if it has spikes or not; in general I use about 70 characteristics to classify each grain. It’s fun. And there are very few paleopalinologists of the tropics in the world. About 20. Imagine that. In Colombia there are five,” he says laughing. “But without this basic science work you can’t do anything else. Someone has to do it. Jaramillo and his group have found at least 1500 new species of tropical pollens from Colombia and the Americas. In fact, 80% of the pollen grains collected have not been described before. “This monograph is a once-in-a-lifetime job. I have a little pounded finger because I say this year I’m going to finish,” he emphasizes, laughing and hitting the table with his index finger. “We already analyzed the pollen but now we have to compare it with other species in the world. For example, there is a very good collection from the Egyptian Cretaceous that has things very similar to what we have here. We had to make sure that what we have here no longer has a name in Egypt. The same goes for collections in Munich and Paris. And in Sydney, whose cretaceous pollen resembles that of Colombia because it was all part of Gondwana.