Hundreds of new visitors came to our Buzz blog last week because their google search for "dinosaur mummy" pointed to my post titled Fossilized dinosaur mummy gets x-rayed. The internet buzz this week is about another dinosaur mummy. A hadrosaur, or duck-billed dinosaur, was discovered in 1999 by then-teenage paleontologist Tyler Lyson on his family's North Dakota property. It is not really a mummy (dried tissue), but a fossilized mummy (composed of rock).
"This specimen exceeds the jackpot," said excavation leader Phillip Manning, a paleontologist at Britain's University of Manchester."
"First the dinosaur body had to escape predators, scavengers, and degradation by weather and water. Then a chemical process must have mineralized the tissue before bacteria ate it. And finally, the remains had to survive millions of years undamaged." National Geographic
CT scans of the hadrosaur's fossilized muscle mass and computer modeling leads scientists to speculate that Dakota (the name given to this dinosaur mummy) could run 28 mph. This makes sense because hadrosaurs were being chased by the Tyrannosaurus rex which topped out at about 20 mph. Scientists warn that errors in computer modeling can be 50 per cent, though.
Most scientists refused to comment until their finds are published and undergo the scrutiny of peer review. Peggy Ostrom, who studies how organisms are related to each other, commented only in general terms.
"It's rare to find an articulated skeleton and even more so to find one with fossilized soft tissue,"
"If such finds show extraordinary preservation, they tempt us to wonder about the possibility of finding [unfossilized] biomolecules that might be remnants of the ancient organism."
The fossil including an entire skull, torso, shoulder blade and various limbs was discovered at Dikaka, some 400 kms northeast of the capital Addis Ababa near the Awash river in the Rift Valley.
"The finding is the most complete hominid skeleton ever found in the world," Zeresenay Alemseged, head of the Paleoanthropological Research Team, told a news conference. Reuters
The fossil has been named "Selam", which means peace in Ethiopia's official Amharic language.
"The Dikika girl stands as one of the major discoveries in the history of palaeoanthropology," research team leader Zeresenay Alemseged said, citing the remarkably well-preserved condition of the bones, the geological age and completeness of the specimen.Cosmos Magazine
The following is the abstract of the original article describing the baby, which was authored by Zeresenay Alemseged, Fred Spoor, William H. Kimbel, René Bobe, Denis Geraads, Denné Reed and Jonathan G. Wynn, and appeared in Nature on September 20, 2006.
"Understanding changes in ontogenetic development is central to the study of human evolution. With the exception of Neanderthals, the growth patterns of fossil hominins have not been studied comprehensively because the fossil record currently lacks specimens that document both cranial and postcranial development at young ontogenetic stages. Here we describe a well-preserved 3.3-million-year-old juvenile partial skeleton of Australopithecus afarensis discovered in the Dikika research area of Ethiopia. The skull of the approximately three-year-old presumed female shows that most features diagnostic of the species are evident even at this early stage of development. The find includes many previously unknown skeletal elements from the Pliocene hominin record, including a hyoid bone that has a typical African ape morphology. The foot and other evidence from the lower limb provide clear evidence for bipedal locomotion, but the gorilla-like scapula and long and curved manual phalanges raise new questions about the importance of arboreal behaviour in the A. afarensis locomotor repertoire."
Additional reading: BBC News
The University of Witwatersrand in Johannesburg South Africa has long been known for its impressive discoveries related to human evolution. Discoveries from Witwatersrand related to human evolution typically emphasized the importance of not only Africa but South Africa in the development of early man. Many of the more famous discoveries related to Paleoanthropology or the study of human evolution come from East Africa — where researchers have discovered, and continue to discover, some of the best evidence for human origins in Africa. Researchers further south, however, continued to argue that fossil discoveries from South Africa should not be discounted from the developing picture of the history of early man.
One of the most significant South African discoveries was the Taung child, which was discovered in 1924 and was given its name when the first researchers to examine the fossil concluded that the specimen was so small because it was a child. This week, researchers from Witwatersrand are announcing that the Taung child could have been killed by a large bird. Yahoo News is reporting that by studying the hunting abilities of modern eagles in West Africa, researchers determined what signs would be left behind on a skull of an animal that was killed by a predatory bird. Armed with this new knowledge, Physical Anthropologists reexamined the Taung child and found traces of cuts behind the eye sockets. Even though the specimen has surely been examined hundreds of times since its discovery, nobody had really noticed the marks before.
Discoveries like this one prove that new discoveries and interpretations can be made by simply reexamining old discoveries with a fresh pair of eyes. No pun intended.
In the field of paleoanthropology, or the scientific study of extinct members of human ancestry, scientists are often asked to stake their reputations on a single claim or hypothesis. The interesting thing about the claims that scholars attempt to make is that they are often based on the very small number of specimens that are available for research. This atmosphere often creates an intense series of lively debates between scholars over the interpretation of their sometimes limited data.