A finales del mes pasado se dio la noticia del hallazgo de unos restos humanos muy peculiares, seres humanos de un metro de altura; esto sucedió en la isla de Flores en el archipiélago de Indonesia. En el blog especializado en estas cosas: PaleoFreak, fué noticia correspondiente durante dos días (1 y 2) e incluyeron buenos enlaces al respecto. Hace 2 días, el 9 para ser exactos, el NYT publicó un buen reportaje con algunas novedades sobre el tema.
Para los no enterados, las peculiaridades de las que hablo, además del tamaño de los seres encontrados, son varias, su cerebro es de aproximadamente 380 centímetros cúbicos, como un chimpancé, y sin embargo usaban herramientas de piedra y parece casi seguro que cazaban en grupo, ambas cosas hasta la fecha asociadas a cerebros más grandes, de homo sapiens vamos. Otra cosa es la edad en que se fechan los restos encontrados, apx. entre 18,000 y 13,00 años, es decir, muy, pero muy recientes, en términos paleoantropológicos.
El NYT lo dice así: The Floresians, whose existence was reported late last month, have shaken up existing views of the human past for three reasons: they are so recent, so small and apparently so smart. None of these findings fits easily into current accounts of human evolution. The textbooks describe an increase in human brain size that parallels an increasing sophistication in stone tools. Our close cousins the chimpanzees have brains one third the size of ours, as do the Australopithecines, the apelike human ancestors who evolved after the split from the joint human-chimp ancestor six or seven million years ago. But the Australopithecines left no stone tools, and chimps, though they use natural stones to smash things, have no comprehension of fashioning a stone for a specific task. The little Floresians seem to have made sophisticated stone tools yet did so with brains of 380 cubic centimeters, about the same size as the chimp and Australopithecine brains. This is a thumb in the eye for the tidy textbook explanations that link sophisticated technology with increasing human brain size.
Modern humans probably exterminated the world's other archaic humans, the Neanderthals in Europe. Yet the little Floresians survived some 30,000 years into modern times, the only archaic human species known to have done so. All these surprises raise an alternative explanation. What if the Floresians are descended from modern humans, not from Homo erectus? "I think the issue of whether it derives from H. erectus or H. sapiens is difficult or impossible to answer on the morphology," says Dr. Richard Klein, an archaeologist at Stanford. And if the individual described in the Nature articles indeed made the sophisticated tools found in the same cave, "then it is more likely to be H. sapiens," he says. The same possibility has been raised by two anthropologists at the University of Cambridge, Dr. Marta Mirazón Lahr and Dr. Robert Foley. Commenting on the sophisticated stone implements found in the cave with the Floresians, they write that "their contrast with tools found anywhere with H. erectus is very striking."
Whether the Floresians' line of descent runs through Homo erectus or through Homo sapiens, a whole new line of human evolution has opened up, even though one that is now all but certainly extinct. The Floresians are not like human pygmies, which have almost normal-size brains but smaller bodies because their growth is retarded during puberty. Nor are they dwarves. The skeleton described last month could be a called a midget, in the sense of a tiny person with the head and body proportions of a full-size person, Dr. Klein said. "I always tell my students that I've taught for 30 years and I've never given the same lecture twice. Hardly a year goes by when something new isn't found," says Dr. Leslie Aiello, a paleoanthropologist at University College London. Of the Floresian discovery she says, "It's a total knockout."
Para los no enterados, las peculiaridades de las que hablo, además del tamaño de los seres encontrados, son varias, su cerebro es de aproximadamente 380 centímetros cúbicos, como un chimpancé, y sin embargo usaban herramientas de piedra y parece casi seguro que cazaban en grupo, ambas cosas hasta la fecha asociadas a cerebros más grandes, de homo sapiens vamos. Otra cosa es la edad en que se fechan los restos encontrados, apx. entre 18,000 y 13,00 años, es decir, muy, pero muy recientes, en términos paleoantropológicos.
El NYT lo dice así: The Floresians, whose existence was reported late last month, have shaken up existing views of the human past for three reasons: they are so recent, so small and apparently so smart. None of these findings fits easily into current accounts of human evolution. The textbooks describe an increase in human brain size that parallels an increasing sophistication in stone tools. Our close cousins the chimpanzees have brains one third the size of ours, as do the Australopithecines, the apelike human ancestors who evolved after the split from the joint human-chimp ancestor six or seven million years ago. But the Australopithecines left no stone tools, and chimps, though they use natural stones to smash things, have no comprehension of fashioning a stone for a specific task. The little Floresians seem to have made sophisticated stone tools yet did so with brains of 380 cubic centimeters, about the same size as the chimp and Australopithecine brains. This is a thumb in the eye for the tidy textbook explanations that link sophisticated technology with increasing human brain size.
Modern humans probably exterminated the world's other archaic humans, the Neanderthals in Europe. Yet the little Floresians survived some 30,000 years into modern times, the only archaic human species known to have done so. All these surprises raise an alternative explanation. What if the Floresians are descended from modern humans, not from Homo erectus? "I think the issue of whether it derives from H. erectus or H. sapiens is difficult or impossible to answer on the morphology," says Dr. Richard Klein, an archaeologist at Stanford. And if the individual described in the Nature articles indeed made the sophisticated tools found in the same cave, "then it is more likely to be H. sapiens," he says. The same possibility has been raised by two anthropologists at the University of Cambridge, Dr. Marta Mirazón Lahr and Dr. Robert Foley. Commenting on the sophisticated stone implements found in the cave with the Floresians, they write that "their contrast with tools found anywhere with H. erectus is very striking."
Whether the Floresians' line of descent runs through Homo erectus or through Homo sapiens, a whole new line of human evolution has opened up, even though one that is now all but certainly extinct. The Floresians are not like human pygmies, which have almost normal-size brains but smaller bodies because their growth is retarded during puberty. Nor are they dwarves. The skeleton described last month could be a called a midget, in the sense of a tiny person with the head and body proportions of a full-size person, Dr. Klein said. "I always tell my students that I've taught for 30 years and I've never given the same lecture twice. Hardly a year goes by when something new isn't found," says Dr. Leslie Aiello, a paleoanthropologist at University College London. Of the Floresian discovery she says, "It's a total knockout."
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