Posted: Sep 25, 2018 2:16 am
by Wortfish
Calilasseia wrote:
Obscure source (and one that took three minutes to load on a broadband connection that normally handles such matters in 5 seconds), but for once, not the usual duplicitous creationist output. Makes a pleasant change.But of course, those of us who paid attention in class, understand that any evolutionary process generates biodiversity, regardless of whether or not it results in a speciation event. Because at bottom, biodiversity is simply genetic diversity within biosphere populations.


Selection is actually the reduction of diversity. It has to be, since to "select" means to choose one over another.
Natural selection sculpts genetic information to limit diversity: https://www.cam.ac.uk/research/news/nat ... -diversity

Natural selection could limit a species' ability to adapt to future environmental change by removing linked variations that, despite having no immediate beneficial impact on the species, could become relevant to its survival and capacity to cope with its environment in the future.


I also found this very handy definition of macroevolution: https://quizlet.com/218260827/chapter-8 ... ash-cards/

Microevolution refers to the changes in the gene pool of a population over generations. Macroevolution refers to speciation, the formation of an entirely new species. Microevolution happens on a small scale within a single population while macroevolution happens on a scale that transcends the boundaries of a single species.


But if that is what macroevolution entails, then virtually all creationists accept macroevolution!

Wrong. It does imply universal common descent, courtesy of the fact that current populations inherited their genetic constitution from relevant ancestors. You do know what the word "inherit" means, don't you?


Just because some species share a common ancestor, doesn't mean all species share the same common ancestor(s). You're forcing a conclusion when one does not necessarily exist.

Oh wait, this is exactly what I was telling you in the above post. You want a cookie for working this out?


Well, yes. But that is why disputing the term "kind" is spurious when essentially all taxonomic divisions above that of a species lack a proper and precise definition. This is a problem facing both the creationist and evolutionist alike.

Once again, point me to a definition of "kinds" that doesn't involve the comedy of the absurd.


At least for sexually reproducing animals:

"A Group of organisms that uniquely share a common ancestor through which they posssess specific synapomorphies. Members of the same kind can normally reproduce with each other even if the offspring is sterile due to chromosomal variations. Physical differences may also inhibit successful reproduction."

It is worth noting that some humans may not be able to reproduce with each other due to genetic abnormalities such as dwarfism. But this does not mean they are of a different kind, let alone a different species.

This is a colloquial term. F for effort.


The taxonomic division, genus, is Latin for "kind".

Except that oops, this is currently a laboratory technique deployed by humans, not something that occurs in the biosphere. As for horizontal gene transfer, this is mostly restricted to bacteria and archaea. It's not documented as occurring between multicellular eukaryotes as far as I'm aware. So basically you're appealing to magic again here?


The point is that genome transplants are a way of getting an organism to use the DNA of another organisms when the physical apparatus of reproduction prevents successful copulation. IVF treatment allows couples to reproduce where normally they would not be able to do so. Genome transplants have been successfully done between the goldfish and red carp.

I don't recall molecular phylogeny saying anything different. Except of course that molecular phylogeny doesn't introduce an arbitrary limit upon common ancestry. So do please tell us all once and for all, how this arbitrary limit is drawn, and for what biologically sound reasons, as opposed to blindly asserting that such a limit exists, in a desperate attempt to prop up mythology written by people who couldn't count correctly the number of legs that an insect possesses.


There are natural limits to biological change, and human experiences with selective breeding have exposed them. These do not mean that universal common ancestry is not possible, but that some factor other than the selection of random variation is needed to bring about major changes, such as metazoan phyla in the Cambrian.