leopold said:
stanley
the age of the earth is not directly known.
All of history is the same in that regard. This just happens to be one of the richest sets of artifacts - plus, we happen to live in an era rich in measurement technology.
it is measured indirectly and has a number of assumptions associated with it.
I wouldn't say that. It's effectively the same as any other valid litmus test.
those assumptions are open to interpretation.
Certainly not open to inferring that the Earth can be younger than 4 billion years old!
The point is you were wrong in your statement that decay rates are immutable.
Yes, decay rates are highly stable, well within the range for measuring the age of the Earth. There is no error in saying that.
Stanley said:
Given the extreme circumstance do you not see a possibility of some event\events changing the way something measured to be billions of years old can literally change within a matter of seconds? Bombardment by solar flares perhaps.
There are few truths as unshakable as the radioactive evidence in minerals. Too may different materials, too many different isotopes, too many different decay rates, too many different proportions of each, too many consistent isochrons . . . in short, the data is too complex and too tightly correlated to infer that it might all be subject to invalidation by any physical anomaly.
this might not be true. different rates of evolution implies a structure related process, not an environmental one.
As we've discussed, there is no process that operates outside of natural selection. And that implicates the environment--although we should be referring to the 'niche'.
maybe only ONE "defect" need arise that just happens to be the catalyst for the change.
Any mutation is a change, but yes, mutation can be a catalyst - merely by its incorporation into the gene flow of a population. But no single mutation will get you from, say, fish to mammals. There has to be all of the history in between, both genetic and 'environmental'.
or, one "defect" that causes a misfolded protein which happens to be the catalyst.
The real catalyst was the evolution of protein synthesis in the first place. It's a process that loads genetic programming, so it's sensitive to mutation in a specific way - it will actually replicate whatever happened to land in the gene as the result of random mutation. It's a crap shoot, and, pays off is any advantage over a niche - the organism will tend to fill the niche and fail outside of it. That brings us back to the 'environment' (evolution of the niche) and natural selection, essential to the overall process.
no, different rates of evo is most certainly structurally related.
Better would be to say that rates of speciation can be attributed to many different chance phenomena - from large impact meteors, vulcanism and plate tectonics to climate change to countless factors leading to extinctions - and that there is no reason to assume that rates of speciation - especially applying such a broad brush of generalization - should fit any prescribed patterns.
structurally as in molecular structure.
As in DNA, you mean--the mother of all such molecules.
something just keeps hanging in my craw about all of this:
life and the universe, both will defy adequate description.
More than adequate for anyone except a researcher. At least we don't have to rely on superstition any more.
The trend says we are converging, never exactly arriving at perfect knowledge.
i believe they have some complete DNA sequences from plants/ animals.
Of course!
doesn't it seem just a matter of time? the same was said after miller-urey too.
...before...? ...synthetic organisms?
could we really be dealing with quantuum physics and the transdimensional?
hmmm... a mystical cause for speciation? Sounds very unlikely, given the abundance of evidence for natural causes.
