BSCS Biology: A Molecular Approach Unit 4:
EvolutionIn the NewsEarly Hominid Fossil Shows Signs of Bipedalism Scientists from the Cleveland Museum of Natural History and from Ethiopia announced that, in February 2005, they discovered the partial skeleton of a 3.8- to 4-million-year-old hominid. Initial study of the fossils indicates that the creature probably walked upright. Most of the fossils are still buried in rock matrix in northeast Ethiopia. The fragments anthropologists have managed to unearth, however, point to tantalizing signs that the find might hold important clues about hominid evolution. Walking upright, or bipedalism, was an important adaptation for early hominids. It allowed them to walk more efficiently over long distances, which probably led to increased travel and the ability to take advantage of new environments. Walking on two legs let hominids raise their heads, allowing them a wider range of vision to spot danger and opportunity. Bipedalism also freed the hands to carry items and use tools. The researchers discovered the fossils only 40 miles from the site where Lucy, a famous early hominid fossilized skeleton, was found. Lucy, too, was bipedal, though scientists are not certain whether she walked upright most of the time. The new fossils indicate a species that, while older than Lucy, was larger and had longer legs. Dr. Bruce Latimer, one of the anthropologists who made the find, says, "Right now we can say this is the world's oldest bipedal, and what makes this significant is because what makes us human is walking upright." Dr. Latimer's assertion that this find represents the earliest bipedal creature is sure to spark some controversy, since other scientists argue that earlier bipedals have been identified. This controversy does not diminish the importance of this new finding on expanding our understanding of the history of human evolution. The more pieces of our lineage scientists can put together, the clearer the entire story of human evolution will become. Sources http://news.bbc.co.uk/1/hi/sci/tech/4322687.stm http://www.cnn.com/2005/TECH/science/03/05/ethiopia.hominid.ap/index.html http://seattletimes.nwsource.com/html/nationworld/2002198458_ancestor06.html |