What do you mean by that? Is there more than one definition? If so, what’s the other one?
On the basis that mutation can introduce randomly oriented small variations in morphology, and that small variations visible to selection can result in large changes. And that Nilsson & Pelger have pointed out a pathway in which accumulated small variations can result in an eye. But again, this is off the topic of common descent.
Common ancestry between organisms of different species arises during speciation, in which new species are established from a single ancestral population. Organisms which share a more-recent common ancestor are more closely related. The most recent common ancestor of all currently living organisms is the last universal ancestor,which lived about 3.9 billion years ago.
Neither of these is part of the definition. Nor does it describe the speciation process; it just says speciation, defined as the splitting of lineages, happens. That’s a necessary consequence of the common descent of different species, isn’t it? And the last universal ancestor is a consequence of universal common descent, not just of common descent. So no, it’s not a different definition at all. I think your problem may be that you don’t know what “speciation” means.
That’s a necessary consequence of the common descent of different species, isn’t it?
You are now adding to your claim which requires speciation to be established. This casual oh by the way adds makes the theory smoke and mirrors. Speciation may or may not occur and the scientific evidence for this process is sketchy for anything more then minor transitions.
Again more smoke and mirrors. Universal common descent gets slipped in without it being solidly established and does not get off the ground at the first transition because of the tremendous differences between prokaryotic and eukaryotic cells.
You have created a definition I can agree with. What I cannot agree with is the stretching of that definition without support into a claim that is merely ideological. This is what Wiki is doing.
You mean I’m the one who tried and failed to teach you about speciation. Or about anything, really.
You can say that only because you don’t know what “speciation” means, I think. The strongest scientific evidence for speciation is that species are related by common descent. What you are trying to introduce is some point about the causes and mechanisms of speciation, which is once more a separate issue from common descent.
Only, apparently, because you don’t understand it.
Universal common descent is a scientific conclusion drawn from evidence. The definition of common descent does not require all life to be related.
The mechanisms of evolution (e.g. speciation, vertical inheritance, mutation, and selection) are an explanation for the patterns of similarities and differences we see in biology. The distribution of characteristics are a set of facts, and the theory of evolution is the explanation for those facts.
No, When we are done I think you will realize you did a pretty good job. It is not necessary for the student to agree with everything the teacher taught.
You are claiming common descent is evidence for speciation. Common descent is some of the observed similarities and differences between species. In this way it may explain some of the way speciation occurs but at best it is an incomplete explanation.
Common descent is an explanation, not an observation. The observations are the similarities and differences. Common descent is part of the explanation for these observations. Again, theories and facts are different things.
Common descent explains why species share certain features. Speciation explains why two populations branched off of one population. The combination of common descent, speciation, mutation, and selection (along with other mechanisms) explains the observed pattern of similarities and differences.
It is drawn form pieces of evidence available where the totality of evidence makes this claim a very big stretch.
The definition of common descent does not require all life to be related.
I basically agree with this. I would emphasize they are incomplete explanations and the question is how complete this explanation is. The marketing of the evolutionary framework tends to stretch its interpretation of the evidence into sketchy conclusions.
In my opinion the ID guys are making an attempt to complete the explanation.
This is where Gould jumps to an assertion. The jury is clearly out here. There is no scientific way to conclude this until the mechanism is understood.
No, I am just showing it is a partial explanation by science sold as a complete expiation by the marketing of science. What surprises me is as a mathematician you don’t see the problems with Darwins theory as stated.
I don’t see how it is an assertion to state that life evolved through the mechanisms found i the theory of evolution or life changed through some other process. Also, there is more than 99% consensus on evolution among biologists.
We have come a long way from Darwin’s original ideas.
As a mathematician, I did see problems. And I was hesitant to accept evolution at first. However, the Crick/Watson work on DNA made a compelling case for evolution. I still had qualms about the adequacy of the traditional explanation. So I took it upon myself to try to understand how it could work.
Having made the effort, I no longer see serious problems with evolution. But there are serious problems with ID.