Posted on 04/13/2006 12:18:35 PM PDT by Senator Bedfellow
When the famous skeleton of an early human ancestor known as Lucy was discovered in Africa in the 1970s, scientists asked: Where did she come from?
Now, fossils found in the same region are providing solid answers, researchers have announced.
Lucy is a 3.5-foot-tall (1.1-meter-tall) adult skeleton that belongs to an early human ancestor, or hominid, known as Australopithecus afarensis.
The species lived between 3 million and 3.6 million years ago and is widely considered an ancestor of modern humans.
The new fossils are from the most primitive species of Australopithecus, known as Australopithecus anamensis. The remains date to about 4.1 million years ago, according to Tim White, a biologist at the University of California, Berkeley.
White co-directed the team that discovered the new fossils in Ethiopia (map) in a region of the Afar desert known as the Middle Awash.
The team says the newly discovered fossils are a no-longer-missing link between early and later forms of Australopithecus and to a more primitive hominid known as Ardipithecus.
"What the new discovery does is very nicely fill this gap between the earliest of the Lucy species at 3.6 million years and the older [human ancestor] Ardipithecus ramidus, which is dated at 4.4 million years," White said.
The new fossil find consists mainly of jawbone fragments, upper and lower teeth, and a thigh bone.
The fossils are described in today's issue of the journal Nature.
Found Links
According to White, the discovery supports the hypothesis that Lucy was a direct descendent of Australopithecus anamensis.
(Excerpt) Read more at news.nationalgeographic.com ...
Well, so far there is one poster that claims to be 4, and you at 65. I'm 35, which makes the average age 34.2. Darn it! I'm over the average! I suspect the 4 year old is lying.
Thats a perceived fact. Read Descartes, I think therefore I exist. Just start with Descartes philosophy. Its on the web. Its the argument against perceived facts by doubt. Necessary in any argument or understanding of philosophy.
How long ago was this? In my assessment you don't seem entirely up-to-date on the theory of evolution.
</Luddite_Mode>
I like you more and more. :-)
He must predate my education in the 50's-60's.
I will do that ...I just read some parts of Job recently, a few weeks ago....I will go back and read Job 38 this evening, if time permits...
I take it you don't think the South will rise again?
But that is exactly what ejroth actually wrote. Are you saying that my quote is false? I don't think so--the original text is on this thread, so you can read it for yourself. This creationist argument has been used often, but as I showed, it is a lousy argument, and if you took it seriously, you could claim that nothing in history is acceptable as evidence. Quoting ejroth: "you can never prove the Theory of Evolution because you 1) were not there to observe the process and 2) cannot reproduce it. "
It is NOT a strawman to refute a posted argument. It is YOU who is running to defend a silly argument.
So, I ask you, using ejroth's argument, do you agree or not that there was a a City of Rome and Caesar lived there? If you agree that, how do you know? What evidence do you accept? Was you there, baby?
From these threads, it is creationists and IDists that manage to mock and ridicule themselves. Ichneumon, Coyoteman, Alter Kater, jec41, and others continue to post valid science, widely accepted by other scientists, and the anti-evolutions present pathetic arguments.
You chose to ignore what ejroth said: The Theory of Evolution has always been and will always be a theory and one that lacks good evidence . For an example of pathetic, that is pathetic.
Ah, at 35, you are just a kid...
An alternative theory: The 4-yr-old might not have learned anything about science and posts here as an anti-evo.
"I take it you don't think the South will rise again?"
:) Tell that to Charlie Daniels.
I hope so because a scientific theory is of a higher order than philosophical proofs, truths and fact. He just doesn't know what he said.
Thanks. Isn't he also considered the father of mathematics?
Coyoteman, I have a question. Can an entire skeleton can be reconstructed based on these findings? How would they go about estimating arm length and such? Would they use previous skeletal fossils to help?
The short answer is Yes.
The longer answer is Yes, but...
In modern humans there are a series of regression formulas for reconstructing missing data. And arm or leg bone can give a good estimate of stature, and with detailed study many bones can provide some clues about others; the calcaneous (heel bone) is weight bearing, so certain measurements can give some data on body weight, stature, etc. These are very specialized studies, but there are experts out there who are very good.
Now the problem; with species that are less known the error rate will go up. If there is little known about a species the error rate could be large.
The fossils in the above article are rare, but not totally unknown. There are other specimens to work with, both before and after, and by knowing the approximate date and distance between chimp on the early end and modern humans on the recent end, fossils which are along that line of descent or closely related can be studied in relation to it. But, some fossils (Paranthropus, Neanderthal) are diverging from the main line and will be more problematic; the degree and nature of the divergence needs to be taken into account.
So, to answer this question, in modern humans the technique for estimating missing data is very good, and the rarer the specimen the more error will creep in. But this is not to say its all just guesswork; it is the result of a lot of careful study. More fossils are the easiest way to get better accuracy, and in the last few decades the east African finds have been spectacular.
I have another question. it's probably a silly one. On the chart, some skulls have two branches off of them. Of those, generally one of the skulls keeps branching, and the other doesn't. Does this indicate an extinction of that line?
The dotted lines in the chart appear to indicate some uncertainty. This chart is a few years old now (2000), and will not reflect the latest finds. When a line ends, that indicates we have no subsequent fossils and assume extinction. That assumption of course can be modified with additional finds. The charts, such as I posted, are simply the best estimates very learned authors can come up with at the time; they are of course subject to change with new data.
Is the timeline determined by comparing it to other fossils, or by the strata in which it was found, or both, or something altogether different
The time period can be estimated using a number of different methods. In Africa, volcanos lay down lava which can be dated using radiometric methods. The layers themselves are usually distinctive, either with particular chemical (distinctive lava or ash deposits or the intervening layers) or fossil markers (anthing from pollen to various plants and animals). As these kinds of things change through time, the presence or absence of particular organisms can help you tell the time. Some of the dating is being done by paleomagnetism, archaeological data (including types of stone tools and other technological markers), electron spin resonance, and other newer techniques. (I don't know much about most of these.)
One part of the puzzle is that there are lots of geologists and other folks out there who deal primarily with non-hominids. Their studies are helping the paleoanthropologists in their quest to figure out the layers and dating in which the hominids are found. For every Tim White, primarily interested in the human line, there are probably dozens of folks studying other aspects of the distant past, and all can share data.
I have not studied fossil man intensely since grad school, but have tried to keep up a little. If I have made any errors, I am sure they will be corrected shortly.
From your questions it appears you are asking that evolutionists show you the reliability of their data and conclusions--a fair request! Hope all of this helps. Let me or some of the others know if you have more questions. Decent questions such as you posed always deserve an answer.
Yep
Is perceived fact the same thing as an axiom. Those being Existence Exist, The law of Identity, and Consciousness.
On average, I tell people I'm 47. :-)
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.