Never mind the lack of human fosils for billions of years, how would humans manage to hid all other traces of their existence for all that time?
Billions of years of human history is one hell of a lot of human history, so where is the archaeological evidence? Why isn’t there one trace of human settlements? Why isn’t there a single tool or man-made artifact? Did they spend billions of years without ever making anything? Without ever affecting their environment in any perceptable way?
Ah, might say bodswood, but is it possible that humans existed for billions of years without making tools? Can we be certain that humans did not eat or cremate (without tools, mind) all of their corpses until the most recent 0.01% of their total time on Earth, when presumably they just started leaving them all over the place?
It appears that, to bodswood, there is no such thing as ‘reasonable doubt’. He would presumably acquit every self-confessed murderer caught red handed because it was possible that his long-lost identical twin framed him and convinced him to lie about it.
Of course I was being a bit flip in my example, but if you can imagine a time before humans, which I don’t think you want to accept, why can’t you see the process as being a very fast forwarded summary of the evolutionary process? In a sense, we sort of trace the process with each new person that grows in the womb. Even there, things happen which may determine the outcome of the baby’s health or characteristics prior to birth.
It seems so intuitive to me I guess that I’m surprised when people have a problem with simple forms developing into more complex forms. Autos progressed from early models like the Model T before we could build upon that to come up with a formula one racer as well.
Better stick to explaining to him “single-celled organism becoming slightly different/better organism” (prokaryotes to eukaryotes, for example) , I would suggest.
I think he is referring to the Burgess Shales , which contain a great variety of Cambrian fossils, and which is described by Gould in his book Wonderful Life. I believe recent evidence shows that these forms did not appear as rapidly as originally thought. Rapidly of course means hundreds of thousands, or even millions of years. You must adjust your timescale from the human to the geological when thinking about this stuff.
Punc eq seems to have gone from controversial to something even Dawkins accepts as obvious now. It is actually a reaction to the thought that evolution proceeds by gradual change. Though Darwin did say that, to contrast it to catastrophism, it is hardly surprising that static conditions will produce few changes, while changes in the environment would produce fairly rapid ones (rapid on geological timescales that is.)
But that’s something we poor humans are not naturally equipped to do. We’re inherently solipsistic, and that restrains our concept of time. So it seems like speciation, common descent, inherited adaptation, and evolution as a whole are just a great big coincidence. Too big. It’s not something we can visualize happenning in our lifetimes, so we cannot grasp it.
And that just plain sucks. It’s hard to learn how to think on an immense scale, and it’s hard to teach it.
Because most living individual organisms don’t fossilize; if they did, we’d be buried in fossils! Most creatures decompose, and the chances that a particular orgamism’s corpse will become permanantly preserved is slim to none. Some organisms that existed left NO RECORD! A lucky few left a few remains behind for us to ponder. Yet others, for various reasons like heavy bone structure or rapid anaerobic sedimentation or sheer weight of numbers, left TONS of fossils.
So, short-lived transitional forms are unlikely to be found, and only extremely successful adaptive organisms are likely to be well-represented in the fossil record.
:D¬
I realize Diogenes posted the above some time ago, but in re-reading some of this thread, I realized that I could use some information supporting this statement, the more fundamental/basic the better (see? I’m just transferring my “fundamentalism” from one belief system to another! )
I’m pretty familiar with Creationist literature and arguments, and a great many such arguments essentially attack the fossil record, as they seem to think that there lies the fundamental (there I go again) support for evolution. Some ammunition would be handy.
Any quick and easy links you can offer toward that end? Thanks.
Perhaps it would help if you made clear what you mean by evolution here - even supporters sometimes get confused.
Evolution, as meaning change in genome over time, mediated by natural selection, has been seen in the lab and in nature today, with no reference to fossils. So that is one way Dio is correct.
Common descent is also demonstrated through DNA analysis, so that’s another way.
The one thing you need fossils for is in finding specific creatures who were common ancestors, and in finding specific transitional forms. But remember, creationists typically misdefine transitional form. They seem to think that a transitional between a squirrel and truly flying squirrel has half a wing, and shouldn’t be able to survive, while we see that flying squirrels in the world today might be transitional, can glide, and survive very well. Every species in the fossil record that hasn’t gone extinct without progeny is transitional, but this never seems to satisfy the creationists.
And the really simple answer is to look at talkorigins.org, which has everything you need, and plenty of links.
As Voyager points out, it depends on how one is defining “evolution”. At the most fundamental level, evolution is about changing genomes over time. The mechanisms whereby this occurs are readily observable in real time, and do not require the fossil record at all for support. Darwin took the route of raising pigeons and demonstrating how selection in general works, then applied that logic to nature in general, pointing out the differences between how humans do the selecting and how nature does it.
A consequence of Darwin’s “descent with modification” is that all living things stem from one or a few original forms. That living organisms today are related to some degree or other is supported by similarity of form, as well as similarity at the genome level itself, the idea being that the more closely related two organisms are, the more similar inboth outward appearance and in molecular make-up they are likely to be.
Another consequence is that the structures or traits possesed by organisms themselves will change through time - that is, not only does the entire organism’s population change, but that change is most typically manifest through the changing of individual traits. Thus we get the discussions about how eyes evolved, or how birds learned to fly, or whatever.
So we basically have three “levels”, so to speak, of evolution: changing populations, changing characters of organisms, and the tracing of lineages from one organism to another. Living organisms can be used as supporting evidence for each of these levels, to varying degrees.
Where the fossil record comes in handy is that it gives us a much larger pool of organisms to work with, as well as adding a significant temporal component to the study. Since the most significant changes are theorized to occur over vast periods of time, being able to actually look back in time, in a manner of speaking, adds that much more evidence. So, we can better trace the changes of populations over time, and we can see more similarities with living forms, which allows us to construct geneological trees showing who’s most related to whom. Individual phylogenies are often being re-worked when new fossils appear, filling in gaps. The evolution of specific traits, such as the mammalian jaw joint, or the foot of the horse, can also be traced quite accurately. This is because we not only find fossils with the correct configuartion of traits to act as an intermediate between A and C, but it also lies in the correct temporal position. If we think B really came before C, then finding B in a rock layer below that of C supports that thought.
As such, the fossil record is less a requirement for the theory of evolution than a boon. We are often lucky to find many fossils, as the process of fossilization is very tricky, indeed. So each find adds to our knowledge, and to a great extent, supports (or falsifies) that which is theorized. It provides numerous opportunities to test theories of descent, as well as how a particular structure evolved. There are, for example, some folks who still do not accept that birds evolved from dinosaurs. These folks typically attempt to ascribe the origin of birds to some other, more generic archosaur (the group that contains dinos, crocs and birds). Nice theory - trouble is, all the evidence to date has failed to support that idea, and has, thus far, supported the idea that birds did, in fact, evolve from dinosaurs. So, the idea that birds are not dinosaur descendents has not gained much favor in scientific circles, thanks to the fossil record. Without the fossil record, we could only really tell that birds and crocdiles are most closely related among living things, but we wouldn’t have a clear picture of how the two groups diverged from any proposed common ancestor, nor would we have a good idea as to how closely related they really are.
None of this, however, really deals with the mechanisms of evolution. That it happens, and how it happens, is, again, readily observable. Deciphering what happened is where the fossil record really helps out.
I based my statement on the supposition that the following three phenomena occur in biology. All three have been directly observed and are irrefutable. To wit:
-biological organisms pass on traits through genetic heredity
-variations and mutations occur in genetic heritage
-mutations and heredity lead to changes in populations and eventually, speciation.
Add one more factor to this, that the earth is very old and that life has existen on earth for a very long time.
If you accept (and really there is no choice but to accept) heredity, mutation and speciation, then those three factors, in combination with vast amounts of time and a sorting mechanism (natural selection), then evolution MUST occur. You would have to show a reason that it wouldn’t. Something would have to stop it.
Tracing pathways would be difficult to impossible without fossils but they are not necessary to prove that evolution occurs.
But is not the main thrust of the creationists that the last one has not been observed? Or do they have to use an odd definition of species to come to such a conclusion?
Do you have a link to a paper or report that can be said to document the observation of speciation?
Creationist denial of speciation seems to come from the concept of kind in the Bible, though I have never seen kind clearly defined. They supposedly form some barrier. Kind does not seem to be the same as species, since one of the explanations of how all those animals fit on the ark is that only a pair (or 7 pairs) of each kind was taken, and they all went on a mad frenzy of speciation, far faster than possible with evolution, once they got off.
Of course the mechanism preventing speciation has never been described.