Convoluted human evolution; Lucy had neighbors (Introduction)

by David Turell , Tuesday, June 07, 2016, 19:23 (2879 days ago) @ David Turell

Another article on the issue:-https://www.sciencedaily.com/releases/2016/06/160606154911.htm-"If "Lucy" wasn't alone, who else was in her neighborhood? Key fossil discoveries over the last few decades in Africa indicate that multiple early human ancestor species lived at the same time more than 3 million years ago. A new review of fossil evidence from the last few decades examines four identified hominin species that co-existed between 3.8 and 3.3 million years ago during the middle Pliocene. A team of scientists compiled an overview that outlines a diverse evolutionary past and raises new questions about how ancient species shared the landscape.-***-"It is now obvious that more than one species of early hominin co-existed during Lucy's time," said lead author Dr. Yohannes Haile-Selassie, curator of physical anthropology at The Cleveland Museum of Natural History. "The question now is not whether Australopithecus afarensis, the species to which the famous Lucy belongs, was the only potential human ancestor species that roamed in what is now the Afar region of Ethiopia during the middle Pliocene, but how these species are related to each other and exploited available resources."-***-"Co-author Dr. Denise Su, curator of paleobotany and paleoecology at The Cleveland Museum of Natural History, reconstructs ancient ecosystems. "These new fossil discoveries from Woranso-Mille are bringing forth avenues of research that we have not considered before," said Su. "How did multiple closely related species manage to co-exist in a relatively small area? How did they partition the available resources? These new discoveries keep expanding our knowledge and, at the same time, raise more questions about human origins."-"Paleoanthropologists face the challenges and debates that arise from small sample sizes, poorly preserved prehistoric specimens and lack of evidence for ecological diversity. Questions remain about the relationships of middle Pliocene hominins and what adaptive strategies might have allowed for the coexistence of multiple, closely related species.-"'We continue to search for more fossils," said Dr. Stephanie Melillo of the Max Planck Institute for Evolutionary Anthropology in Germany. "We know a lot about the skeleton of A. afarensis, but for the other middle Pliocene species, most of the anatomy remains unknown. Ultimately, larger sample sizes will be the key to sorting out which species are present and how they are related. This makes every fossil discovery all the more exciting.'"-Comment: One of the persistent questions raised by some paleontologists is how do we know that these aren't all the same folks with just a variation like we see in today's people?