markearthling

Swansont When you refer to pop-sci books perhaps you are referring to the works of one Richard Dawkins ? Are you seriously suggesting that his work has anything to do with physics ? Sorry but there are holes in his arguments big enough to sink battleships. ROFL

Why would proto wing flaps develop in the first place ? What would trigger this ? If a creature is damaged by a fall but does not die this does not mean it would then survive to procreate. In fact it may die later from it's injuries for many reasons. Your argument is not water tight. Also why have other gliding animals not then developed flapping wings as Mr Dawkins suggests ?

What Mr Dawkins has to say is interesting but not entirely convinceing. Quote/Extract Dr Dawkins (above) Natural selection will then favour slight, prototype wingflaps. When these small wingflaps have become the norm, the critical height h will become slightly greater. Now a slight further increase in the wingflaps will make the difference between life and death. And so on, until we have proper wings. there is a continuous series of gradations to gliding wings, and hence to flapping wings. End Quote If a creature has proto wing flaps and falls and damages itself then I can't see how this confers any benefit which would help the creature get around or survive to procreate. So how would natural selection then favour undeveloped wings ? There is a vast difference between the structure and function of gliding and flapping wings. This is only one example of where Mr Dawkins tends to draw a very long bow with his material (to the point of not being credible). If proto wings damage their owner where is the impetus or trigger for them to keep developing ?

It seems likely this would have to start with something small and light (insect ?) which could be lifted into the air by a strong wind/breeze and which would develop bud like appendages which later develop into full blown wings in later generations ? The question is , what is the impetus or trigger which causes the immature wing buds to confer some kind of benefit or advantage to the individual so it is more successfull and survives to procreate and so wings get larger, develop and become more and more successful and usefull ? Some animals which have the power of some kind of flight are various insects, pteradactyl/dino etc., birds, gliding animals and flying fish.

Drop stones have been found in deserts in Australia and elsewhere but I am not saying deserts are the only places they are found. Apparently they also carry a unique magnetic signature which supposedly fixes their point of origin. Moontana says above that the snowball earth phenomena is based on speculative ideas and then goes on to say that snowball earth has happened more than once. A little confusing or is that just the scientific technique at work again ? Ophiolite is not convinced about total global coverage of ice and yet this idea is based on rock solid science. Noone has yet explained convinceingly why volcanism just shut down 650 million years ago for 25 million years (doesn't sound credible) to the degree that runaway weathering out of CO2 tipped us into snowball earth. Whether volcanism is variable or not doesn't mean no volcanism for 25 million years ?

Ophiolite Well you obviously possess an unshakable faith in science. Faith though is not the issue, it is the findings and the interpretations that are at issue. You have misread me totally my friend for my mind is open and that is the only way we continue to learn new things. I would be particularly interested in any purported evidence you can point me at regarding speciation. If it has been observed then this is the first I have heard about it. Anything you care to put my way I will make an effort to read. Richard Dawkins is a case in point. I have read a couple of his books and he is a story teller extraordinaire. His ideas are very interesting until you realise that they don't seem to be backed up by much hard scientific data. I can see many holes and weaknesses all through his work. Plausible arguments don't necessarily substitute for reality. Mankind still has a long way to go and a lot to learn. If we don't recognise this fact we will simply become arrogant, deluded and go backwards. Who was it that said something like, "We are only now standing at the edge of the sea of knowledge" ? So lead on. I am prepared to meet your challenge over time. Also I am not sure whether this is the appropriate place to continue this as per swansonts' reminder. So if it has to be moved this does not bother me.

Ophiolite 1. I came to this forum initially to discuss some concerns regarding radiometric dating. You were in fact the one who first raised the subject of creationism and if we are only talking about carbon dating then you also raised the subject of dendrochronology. 2. Quote/ Ophiolite Individual scientists, being human, may occassionally be dogmatic, but science has no room for, or tolerance of dogma. and (In science all acceptance is provisional: dogma is prohibited.) End Quote How convenient for you for as to dogma you can have your cake and eat it too. It sounds like you are one of the select few who can apply dogma when it suits you. You are almost religious in your precious approach to the subject. 3. As to your comical remark about dolphins walking down the main street relating to rate of decay, if your evidence is so overwhelming then present it. 4. Evolution theory is just that, theory and unsubstantiated ideas. Supposedly we have overwhelming evidence for this. Where is all this conclusive evidence by the way ? When it comes to evolution, science definitely has an agenda and it is ,"come hell or high water we support evolution". This is your dogma but I forgot that scientists are human and only they are allowed to be dogmatic at times when it suits the theory of evolution. The only thing that works in evolutionary theory is Natural Selection as this can be demonstrated in living species today but this only covers the intrinsic built in genetic variability of species which is why adaptability of species is possible BUT this does not demonstrate any evolution. Cases in point are horses and dogs, how they have changed over time. Again this demonstrates built in genetic variability NOT evolution. Speciation is an interesting idea but there is no evidence to support it. Chemical resistance of bacteria is also due to genetic variability and NOT evolution. The Cambrian explosion has generated extensive scientific debate. The seemingly rapid appearance of fossils in the “Primordial Strata” was noted as early as the mid 19th century, and Charles Darwin saw it as one of the main objections that could be made against his theory of evolution by natural selection ( genetic variability NOT evolution ). 5. You mentioned embryology above. Have you considered how awesomely complex the process of embryo development is ? It is suspected now that the genetic introns code found between genes on the chromosomes is actually not padding/nonsense but regulatory DNA which controls timing and rate of production of proteins specified by the genetic DNA. Yet these highly complex programs for embryo development are all encoded in our chromosomal DNA. How do you suppose this was all encoded by a mindless chemical process that relies on purely random processes for change ? An embryo not only develops but then changes chemically through juvenile and then adult phases. A mindless random chemical process made all this ? Evolution seems not only to have an intrinsic crystal ball but also to be able to see around corners. The design of the DNA has to produce a viable individual which needs to progress through many chemical phases in order to survive and procreate. This cradle to the grave program is encoded in our DNA by what ? A mindless random chemical process ? 5. If you are honest at least to yourself you will see how improbable the claims of evolution are. Evolutionary theory is full of holes and weaknesses but it is supported to the hilt because our precious theory must be kept alive at all costs. 6. To HAL above I say that in many circumstances there are large discrepancies which emerge from radiometric dating work. I am not convinced that all scientists are being that objective when they interpret their results. If there is a discrepancy there is always a reason why we can conveniently massage the data and make it fit evolutionary theory. When people stop doing this and actually look in other more plausible directions for answers then I will give radiometric dating a more favourable viewing.

Ophiolite Just because we have no evidence at present that decay rates may have varied in the past doesn't mean that the fat lady has actually sung on this one yet. Are you actually saying that our knowledge of atomic structure is now complete ? Most things are actually open to interpretation in one way or the other. Science conveniently interprets it's findings all the time. Have you not read about any disturbing discrepancies in the dating findings ? Here is my surmise. "Something" intelligent created life on this planet. Think about the possibilities. You believe that life just built itself. That's not an illogical stance to take now is it ? Everything we make requires intelligence and yet a single cell, DNA, life and man just popped out of a chemical soup. Do you really know what you are talking about ? Do you know about the awesomely complex chemical machinery in one single cell or how these different cells fit together to form multicellular life in all it's different forms and phases ? DNA is an information molecule and it has been encoded by something intelligent. How much time do you think there was again to build all this ? You need to keep an open mind and question what you base your shaky principles on. There are also other interesting theories such as string theory and M theory which suggest the universe may not be what it seems and there may be more out there than is known. The universe is only a subset of the whole. Knowing something about atomic and cosmic physics is only a small start. Also dendrochronology has limitted application for supposedly really old samples (thousands of years at most for tree ring dating).

Moontanman So how do people know how much vulcanism was happening at different times in the past ? It still seems likely to me that vulcanism would have counteracted weathering. So a snowball earth could not form in the first place. Are we saying that for 25 million years vulcanism reduced and then magically ran rampant and melted the snowball ? Where is the proof that this ever happened ? The weathering argument is not convinceing. Sounds like a pseudo science argument.

Gday Do the accuracy/relevance of these dating techniques ( C14/C12 one example) rest on some critical assumptions such as : 1. How much C14 originally present in sample. 2. No sources of contamination such as material leaching into samples. 3. decay rate has always been constant. It seems that if any of the above assumptions are false in any given case this could vastly affect any "accurate" result we are expecting. Our dating techniques may not be what they are cracked up to be. Interested in what others think.

Gday This process supposedly started 650 million years ago when all the worlds' land masses were grouped together in a supercontinent positioned near the equator and runaway "weathering" took massive amounts of CO2 out of the atmosphere and hence lowered the earths' temperature so that massive ice sheets formed and extended from both poles towards the equator eventually covering the whole globe. Supposedly the earth was an ice covered snowball like this for another 25 million years until vulcanism eventually reversed this situation and the green house gases produced melted most of the ice and raised the earths' temperature again. I am assuming that vulcanism has been ongoing since the earth formed. If so then there seems to be a big problem with this theory. Surely vulcanism around the planet would have always been pumping more CO2 and other greenhouse gases into the atmosphere so this would have counteracted any effects of weathering out of CO2. I can't then see how any snowball earth process could have gotten started let alone lasting 25 million years ( again no vulcanism ?). Drop stones are another point in question here. People assume that because these things are found in deserts that they point to transport by glaciers dating back to snowball earth but the truth is they could have been depossitted by glaciers from any ice age in the past. I am informed the earth has ice ages around every 100,000 years which gives us a few to choose from. Interested in what others think about the snowball earth idea.