This month looks like it is mostly new developments reported in the history of our own lives. There are a lot of exciting things going on in this area. Last month I wrote about the possible early arrival of Americans from Asia by boats. Look what I am reporting this month below.

Cactus Hill, Virginia has been found to be a site where early Americans lived some 20,000 years ago. This conflicts with the Asian source theory. This was reported at the recent meeting of the Society for American Archeology in Philadelphia. This means that the Europeans traveled here by way of a land-water route along the ice sheets that covered the North Atlantic (between 16,500 and 22,000YA). How do they know this? Artifacts and weapons have been found. Many of the artifacts resemble those used in Europe (rather than Asia). In addition, they have found DNA markers that are found in Europeans and Native Americans, but not in Asians. Also there are more Clovis sites in the southeast than in the west. Dating suggests that they are also older. The earliest Clovis sites in the West date to 13,500 YA. The Cactus Hill site appears to have been used over many time periods with Clovis materials being found first. But lower levels indicated a series of inhabitation over thousands of years. They found charcoal, tools and animal bones, indicating they were hunter-gatherers. Some of the artifacts found are similar to those of a culture in northern Spain at the same time. There is no reason to believe that they did not have the ability to build boats to cross any water along the way. This theory adds a new exciting angle to the inhabitation of America.

NEANDERTHAL CONTROVERSY

Did modern man drive out Neanderthals or did they interbreed? This is a question that even came up in our recent Paleontology Group Meeting covering hominid evolution. In the March 30 issue of Nature there is an article discussing the analysis of mitochondrial DNA from other Neaderthal bones found in Mezmaiskya Cave in the Caucasus Mountains. In essence it matches the DNA analyzed from bones from the Feldhofer Cave in the Neander Valley, and both are different from that of modern man. This is more evidence for those who say that the Neanderthals did not contribute to the modern gene pool. And then I picked up the April 2000 issue of Scientific American and found an article called "Who Were the Neanderthals?" The subtitle is "Controversial evidence indicates that these hominids interbred with anatomically modern humans and sometimes behaved in surprisingly modern ways". Another fossil mentioned in this study is that of the "Hybrid Girl" (called Lagar Velho 1) found in Portugal who displays features of both species. She is a 4-year-old buried ceremoniously 24,500 years ago (after Neanderthals were thought to be extinct). The moderns are believed to have arrived in Europe about 30,000 years ago so that this child would not be from a rare interbreeding event, but the result of years of interbreeding. The controversy includes the interpretation of tools found at various sites. Some Neanderthal sites contain tools like the moderns brought in and some do not believe that they could have developed such similar tools independently. Were the sites disrupted and levels mixed or did both groups develop very similar tools separately or did the Neaderthals learn the technology from the moderns? Both sides offer explanations but there is still not enough evidence to answer the pending questions. About all both sides will agree on is that Neanderthals were not really slow shuffling cultureless beings. But beyond that, the discussions continue.

KNUCKLE-WALKERS

An article in the March 23 issue of Nature by Brian Richmond and David Strait of George Washington University studies skeletons of early humans to help solve questions about the ancestors. They have examined the wrist bones from several Australopithecines and determined that some were knuckle-walkers. Lucy (Australopithecus afarensis) who lived between 3.0 - 4.0 MYA was included and was shown to have wrists that could lock the hands in place while knuckle-walking. Later ancestor Australopithecus africanus had flexible wrists that were not suited for that kind of walking. This appears to indicate a strong evidence for close evolutionary link of humans with chimps and gorillas with a common knuckle-walking ancestor. However, it complicates the relationship between A. afarensis as the ancestor for the more ape-like A. africanus. Because A. afarensis shows many characteristics of an erect bipedal walker, the knuckle-walking could be considered as a non-functional retention from a common ancestor. It is considered to be less likely that it used bipedalism, knuckle-walking and climbing. However, if you say that one characteristic (knuckle-walking) is considered retained, primitive, and non-functional, how can you say that another characteristic (climbing) should not be treated the same? Was Lucy a striding biped with many non-functional primitive characteristics or a walking, knuckle-walking, climber? It makes one wonder what characteristics in these skeletons that are found are meaningful and how should the bone shapes and implied functions of them be interpreted? It will be interesting to see the reactions to this interesting study.

Hot news from our own neighborhood was reported by Daniel Gebo et al from Northern Illinois University in the March 16 issue of Nature. They have found the foot bones of the oldest anthropoid, Eosimias (the dawn monkey) in middle Eocene China. These tiny fossil foot bones help to place this animal as the first species on the anthropoid branch of the tree. The bones indicate structures that will help adapt later species to walk on all fours. Their importance is the fact that they have characteristics of both the more primitive prosimians and of later anthropoids. Some argue that Eosimias is more like the tarsiers, and a complete skull would help in its interpreting its true place. To find the bones took years of sorting through mud and debris from a rain forest 42 MYA. They also found bones of other small animals including bats, rabbits and a small rhino. They are continuing to sift the dirt in hopes of finding more bones of these fascinating and tiny animals. The two foot bones in the article are on view in the Life Over Time exhibil hall of the Field Museum at the current time. A small magnifying glass sits over them to help them be seen. It is amazing how they can reconstruct an animal from so little!!