Geology and Earth ScienceBones of prehumans dated to 4.5 million years
Wednesday, January 19, 2005 Posted: 2:09 PM EST (1909 GMT)
(AP) -- Paleontologists working in Ethiopia have discovered the remains of at least nine primitive human ancestors that are up to 4.5 million years old.
The specimens belong to a hominid species called Ardipithicus ramidus, a transitional creature with significant ape characteristics. The fossils are mostly teeth and jaw fragments, with some hands and feet bones, according to nine researchers from universities in the United States and Spain.
The discoveries were made over a four-year span beginning in 1999 in digs at the As Duma site in Ethiopia's Afar region, which has yielded many important fossils. The details appear in the latest issue of the journal Nature.
Among the specimens, the recovered canine teeth are smaller and blunt, similar to those of other human ancestors. But most of its teeth, including molars, are like those of great apes. The size and wear of the teeth suggest A. ramidus ate a plant-based diet, the researchers reported.
Geological and radiocarbon tests show the specimens are between 4.3 million and 4.5 million years old.
Scientists know little about A. ramidus. A few skeletal fragments suggest it was even smaller than Australopithecus afarensis, the 3.6 million-year-old species widely known by the nearly complete "Lucy" fossil that measures about four feet tall.
Evidence from other A. ramidus specimens shows its skull rested directly atop its spinal column, rather than in front like apes. This suggests it could walk upright, or had bipedal abilities.
Other fossils found at the As Duma site show that A. ramidus lived alongside monkeys, mole rats and cow-like grazing animals. But details of the environment are sketchy.
Originally, scientists theorized that the earliest human ancestors lived on the savannah and began walking upright to see across the open landscape. But pollen and other evidence from As Duma suggest the diverse habitat had swamps, grass and even some woods.
The first A. ramidus fossils were reported in 1994. With the nine additional specimens, labs now have fragments from as many as 60 individuals.
(AP) -- Paleontologists working in Ethiopia have discovered the remains of at least nine primitive human ancestors that are up to 4.5 million years old.
The specimens belong to a hominid species called Ardipithicus ramidus, a transitional creature with significant ape characteristics. The fossils are mostly teeth and jaw fragments, with some hands and feet bones, according to nine researchers from universities in the United States and Spain.
The discoveries were made over a four-year span beginning in 1999 in digs at the As Duma site in Ethiopia's Afar region, which has yielded many important fossils. The details appear in the latest issue of the journal Nature.
Among the specimens, the recovered canine teeth are smaller and blunt, similar to those of other human ancestors. But most of its teeth, including molars, are like those of great apes. The size and wear of the teeth suggest A. ramidus ate a plant-based diet, the researchers reported.
Geological and radiocarbon tests show the specimens are between 4.3 million and 4.5 million years old.
Scientists know little about A. ramidus. A few skeletal fragments suggest it was even smaller than Australopithecus afarensis, the 3.6 million-year-old species widely known by the nearly complete "Lucy" fossil that measures about four feet tall.
Evidence from other A. ramidus specimens shows its skull rested directly atop its spinal column, rather than in front like apes. This suggests it could walk upright, or had bipedal abilities.
Other fossils found at the As Duma site show that A. ramidus lived alongside monkeys, mole rats and cow-like grazing animals. But details of the environment are sketchy.
Originally, scientists theorized that the earliest human ancestors lived on the savannah and began walking upright to see across the open landscape. But pollen and other evidence from As Duma suggest the diverse habitat had swamps, grass and even some woods.
The first A. ramidus fossils were reported in 1994. With the nine additional specimens, labs now have fragments from as many as 60 individuals.
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The discovery of NINE specimens of the hominid species called Ardipithicus ramidus, is a truly historic one. If the scientists who made the discovery are correct then this is probably a link to our earliest ancestors, stretching 4.5 million years! This is a mind boggling discovery and it brings great interest to me since I’m taking an anthropology course this semester. In anthropology we learn about the discovery of “Lucy,” the skeletal remains of what was once believed to be the earliest ancestors, dating back only 3.6 million years. Being able to bridge another million years on to our evolution and family tree is giant step forward to the science community in understanding our origins.
There are a few things in question in making certain that this is a direct ancestor of ours though. The fact that the specimens skull sits directly on top of the spinal chord and has the hip structure that would suggest that it had bipedal abilities (walking up-right), is a good indicator that the two of us are related, but how can scientists be absolutely sure? There is also evident that the specimen’s teeth are rounded mostly and blunt like our own. It is believed that the animal ate mostly plants for its diet, so let us not forget that we are omnivorous. There was also substantial evidence that the environment the animal lived in was filled with plants, was swampy and even had forests. This would contradict what traditionally is believed by scientists that the earliest humans developed on the Saharan plains and need to stick their heads up and walk up-right in order to see the wide open space in front of them. Darwin lead a great deal of research concluding that we were the descendants of large apes, scientists now believe that we are actually the descendants of small monkeys that were driven out of the forest and onto the plains by large apes. The specimens indicate that we might not have left the forest instead.
With so many holes in the evidence, how can we immediately jump to the conclusion that this animal is one our earliest ancestors? I think of the example given between cats and tigers. Cats and Tigers are part of the same family tree, but did tigers evolve from cats? Of course not. Scientists have a bad habit of rushing to conclusions when it seems there is any link or trace of a major discovery. We need to be able to account for these discrepancies and it may take a very long time to verify there hypothesis. We would have to rethink everything we know about our earliest origins and rule-out a lot of work and discoveries that have come before.
Still, this is a break through even though scientist and anthropologist alike have much work cut out for them. Every time we come closer to linking and discovering our past we come close to discovering what lies in store for humans in the future in my opinion.
Like some other students,I am also learning in Anthropology about “Lucy”, the 3.5 mya bipedal (2 legs) human ancestor and am quite intrested in what science has unveiled.Scientists have discovered the remains of Lucy and nine other primitive human beings dating back to 4.5 million years! It has given scientists hope into discovering the missing links of the evolution of man. Lucy, like most of the others, had a small ape like brain. It was believed that an ape with a big brain evolved into a human, and this is how humans evolved. The article points out that from other A. ramidus specimens , it’s skull rested directly atop its spinal column, rather than in front like apes. This suggests it could walk upright. It also shows it is turning into a different species. We as humans have relatively larger brains, more than half the size of a chimp brain. Does this imply that bipedalism leads to a larger brain? I believe as the primitive humans started walking and using their hands it resulted into homosapiens. This seems like the first step of becoming human? With the use of hands their knowledge grew and possibly their brains got larger and more complicated..Maybe?, which evolves into the size of a human brain. This is all just speculation.There are a number of questions involving the Ardipithicus ramidus that are still unconclusive and scientists are readily searching for answers. Such as discovering the primitive human that aquired the size of a human brain other than a small brain. Lucy and some of the other specimans are the look of a half human, half ape creature( in a transitional period). The fact that the recovered canine teeth are smaller and blunt, similar to those of other human ancestors. But most of its teeth, including molars, are like great apes, makes a very remarkable fact…there could possibly be a link between us? Could we have possibly evolved from small monkey’s? Personally I need to see hard facts on such a topic or I can not believe it is true.I believe once scientists are able to link the all the pieces together a great number of believers will amount. However, it is known that major evolutionary events occur along with major enviormental change, and it is a definite that the earth’s climate was changing at that time. Even the article states the A. ramidus ate a plant-based diet. Probably around that time there was lots of grasslands filled with plants. It still seems strange to conceive the idea that we are related to these primitive humans, and that through years of evolution man was born. It is only recent that we have made these discoveries but the discovery has progressed into the result of finding fragments from as many as 60 individuals! Within the last 15 years Scientists have accreted so much information on such a highly debatable topic. I believe very soon Scientists will be able to solve many of the discreprancies and discover the answer to this boggling discovery.
I found this article very interesting. To think that paleontologists discovered bones dating back to 4.5 million years ago is amazing! These weren't just any old bones, they were among the first primitive ancestors of humans today. The remains of the species called A. ramidus also validates the widely accepted theory of evolution, that humans evolved from apes. There are aspects and characteristics of this species that puts it right in between apes and humans. With canine teeth similar to humans and molars similar to apes. It's astonishing that scientists now have remains that suggest the evolution that took place over millions of years. The A. ramidus' skull rested directly on top of its spinal column which suggests it was able to walk upright on two legs instead of all fours. This would seem like a logical conclusion to assume it is our early ancestors. But according to the size and wear of their teeth, A. ramidus was a plant-eater, but we eat both meat and plants. So is it possible that over time our tooth structure and eating habits changed and we became ommnivores? I would say so. Humans are known to be quite adaptable to their environment, so I feel it is very possible that even our early ancestors easily adapted to their environment. Maybe there was a shortage of plant matter and they had no choice but to expand their diet and thus become omnivorous. It still amazes me to think that we have the technology and knowledge to date fossil remains back to over 4 million years ago. With this sort of evidence of past life, it helps to answer a lot of questions about our ancestry and origin of our species.
This sort of a find definitely leads me to think we are getting closer to people actually agreeing with the theory of evolution. It seems to me that a discovery of over sixty individuals that are closely alike to us, with a similarity in teeth and bipedal abilities, would be enough to sway a person into considering evolutionary predecessors of man as a possible response. It could either be that they are earlier forms of human, homo sapiens sapiens, or they are an extinct group, which at some point, branched off the evolutionary tree. Whatever they are, they are definitely more similar to man than to ape. And why wouldn’t they have continued to live along-side us if they weren’t our predecessors? Would we have killed them off in our history? That seems highly unlikely to me. I would like to hear the thoughts of a person who believes in the theory of ID in regards to this find.
I am pretty sure that they must have been our earlier man. I am a firm believer in the theory of evolution. I can’t think of a reason why not to be. I am interested in this find and all discoveries that push forward to support the theory of evolution, but not because of this debate between the ID theorists and the evolution theorists. I believe that if our species survives whatever may come, we will, of course, evolve. And whatever we survive through, what may happen would have a lot to do with how we evolve. I think that the information we learn from our earlier man, their struggles, their biology, their culture, can help us to predict what we will face in our future as man. Learning what we had been through and how we had adapted may even help us to survive whatever we will face, for example a huge climatic change, or a period of sparse food. This would also help us to develop new ideas and technologies.
The pace at which we are going involving the development of technology, chemicals, synthetics, man-made products in general is absolutely doubling itself over and over. The computer has only been around less than a century. To think of the size and speed that it ran when created as opposed to now, with our wireless satellite internet services and pocket sized devices. Things like this invention will cause us to evolve at a faster rate than ever expected. In fact, I believe we are all going to see it before this century ends, right before our eyes.
This is why I believe these discoveries are so important. We are so wrapped up in technology (which I do believe we should advance in), the media, and other artificial things that are basically running this world right now that we forget. We are living on a living planet and we don’t decide what it does and we probably won’t be able to control it with our technology if it’s going to change climate, and so on, at least right now. So, paying attention to the past and our physical differences, our survival methods, and instinctual behavior at that period might help us out in the future.
this is a ver interesting article to know that we dated all the way back to 4.5 millions years ago. It took them 4 years to relize this but hey to know that we been around for that long is interesting. another thing since they have a few of these fossils we can decide if how we are today is the same way we were back them. Even though they didnt find a exact replica of the kind of teath we have to tady we can tell they used curtain teath for diffrnt things. It is also interesting to show how we arnt much like apes anymoe with the skulls being directly on top of the spinal cords insted of infront showed that we can run and escape form harsh environemts and use hands for defense insted of just running because as a ape u only had four feet on the ground. This answer alot of questions about how we are and arenot like apes.
I found this article to be pretty interesting. This discovery is a huge accomplishment to the scientific community. It is a pretty big gap that they were able to close. From 3.6 million years to 4.6 million years. That’s a whopping one million years difference. It is amazing that we can trace our ancestors that far back. I also found it interesting how from just a few bones they were able to come up with so much information. One example is how they were able to determine that the A. ramidus’ diet consisted of plants based on the size and wear of the teeth. Another thing I noticed is that in the article it mentioned that the A. ramidus was much smaller than the Australopithecus afarensis. It seems that as we evolved throughout the ages we got a bit bigger. The fact that it could walk upright is also pretty amazing. I can almost picture the A. ramidus in my head walking among the other animals that the article mentions, (monkeys, mole rats and cow-like grazing animals) eating leaves from a nearby tree under the hot Ethiopian sun. I wonder if the Discovery Channel or TLC did a documentary where it shows a computerized image of what the A. ramidus would have looked like. Like a re-creation of the picture I have in my head. I’m sure they already have but I don’t watch much television so I don’t know. If somebody knows please let me know. This article made me curious to find out more about the differences between the A. ramidus and the Australopithecus afarensis. I don’t think my curiosity is enough for me to take an Anthropology class but enough to make me look it up on my own. I hope that more research is done the more information can be obtained about how the A. ramidus lived and how long it lived. I also wonder if more discoveries will be made in the future where we can date our ancestors even further than 4.6 million years. That would be interesting. I am sure that if that happens I would guess that the bones would show a decrease in size compared to the A. ramidus. But just like with all other hypothesis and theories, there will be a lot of questions that will shadow the whole thing. But I guess this can be a good thing because it means that more accuracy will be demanded. This discovery re-affirms the theory that we humans evolved from apes and that Africa is the cradle of our civilization, where it all started.
Posted for Liz
This article was very interesting to me, to learn that remains of nine primitive human ancestors were found, dating back 4.5 million years old. This is truly remarkable. This is evidence that maybe we did evolve from apes. These remains suggested transition from apes to humans. Ardipithicus ramidus, Like Lucy, her head sitting on top of her spinal column rather than in front suggest she possibly evolved from apes over years and years. Lucy was the first to stand up right, suggesting change in evolution. Scientist are not 100% sure on why Lucy’s head did sit on her spinal column as apposed to apes, there heads sit forward, scientists believed that A. Ramidus used there heads to see across the open landscape, and began walking upright. However, evidence like pollen suggests that during that time it was a diverse habitat that had swamps and woods. But, how do we know they didn’t start walking up right for survival purposes? Maybe there was food in trees that made the Ramidus stand up right to reach. Scientist did say that they survived off plants. There are so many missing links to all of this. Lucy was only 4 ft tall which suggested that probably all A. ramidus were around the same height, how does that bring humans like us to be so much taller?
Ardipithicus ramidus maybe did not evolve from apes, however they did have ape characteristics, one example is the molar teeth, they were similar to great apes.
So why are apes still hear today? Why didn’t the A. Ramidus stay alive? Why didn’t cave men stay alive? Many scientists say that we evolved from apes, to cave men, to what we are now? Is that why we don’t see A. Ramidus today? Because we evolved from them? But with that said then why are there still apes? There are so many questions that need answers.
I still find it amazing that remains of primitive human ancestors were found. Labs have as many as 60 individuals. These may help us with the future… Maybe we will keep evolving?... We will probably never know.
This article was very interesting and was fulled with useful information. I would love to see the actual bone fragments of A. Ramidus and even Lucy. Although I took anthropology last semester, i never learned about Lucy, instead i learned about groups of people who lived in differenst areas of the world. What they ate, what their economy was like, what their beliefs were...it was really boring. I would have loved the class if it talked about findings such as Lucy and what our first ancestors were like. I had to actually ask a coworker what Lucy is! From evolition, i learned thatthe first animals are not born to fit their environment right awat, They have to learn how to adapt. An example, is the giraffe. At first, they had short necks, and over time as trees began to frow taller, theirnecks did as well. If Lucy is 3.6 million years old and she was only 4 feet tall, why is A Ramidus smaller than her, if he is 4.3-4.5 million years old? Are they not suppsoed to gradually be gettin taller in height? Besides that, the new jaw and teeth fragments were small and blunt, like ours. It is not suprising, because they lived in an environment filled with swamps, grasses, and woords, as the evidence showed. Eventually, if it was necessary to survivial, they would befin to eat omnivorously as were are. To adapt totheir environment, their teeth would gradually change size and shape, just as the giraffes' necks did? The fact that A. Ramidus specimens sjull rested on top of its spinal column shows us that it was able to walk upright and on two feet. This is a sign that development of homosapiens was gradually taking place.
I find this article hard to accept. To date human existence to 4.5 million years ago is bogus to me. I can’t even believe that “Lucy” is an ancestor to humans. This article seems to be opening up the case that humans evolved from apes again.
If what the scientist’s are saying in Ethiopia is true, then tell me how a three-foot tall, gorilla-like species turned into a 5’4 blonde hair, blue-eyed woman. I understand that this is an extreme and that evolutionary events took place for this to happen. but the theory. in general, is extreme.
I don’t want to completely be against these findings. I do think it’s great that we are still finding things out, and discovering new things everyday, that’s what makes science classes so interesting. Reading articles like this are interesting, but brings up so many questions to me and probably to many more people as well.
Science has completely changed my learning as a child, God put us on Earth. Many people may view that as a bad thing, but if what this article is telling me, that human ancestor’s lived 4.5 million years ago, and that they have some proof, what am I suppose to believe? In all honestly, I don’t like it and I don’t want to believe it. Until there is a concrete answer to what humans evolved from, I’m going to stay believing what I was told as a child.
So we came from Apes? I don't know what to believe. God says one way but scientists now say another. Yes we may have some same characteristics as apes and monkeys but i never could understand how we changed from them to humans and that not all apes are humans now. What’s different from then to now that we changed from apes to humans. I want to see actual evidence that says this was possible and that this actually took place and changed species. To be dated all the way back then seems a little far fetched. I can't see humans living all the way back to that time as I never heard anything about humans dating back that far. I know that we have the technology to date things back that far but I’m not a firm believer as none of us never really lived then and actually don't know the actually truth behind what we tell. I don't think we can say its a fact when the proof we have we can't ask someone was this how it was really like and this is exactly how it happened. I take scientists words but not all the way to be yes there right this did happen when there isn't really any truth behind the unknown. Its like with religion and having god say he created humans. well we live by what were told and told what to believe but we don't know the truth as we really don't know the truth about apes and humans. If you can show me actual evidence and something that believable I’ll ten go along with it. But right now, its just stories of how things were believed to have occurred.
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