Evolution and Increased Diversity

Isn't that like saying the color of your new car is the result of your choice in the showroom and not the result of the pigmentanation in its paint? I'm gonna strain my brain to get this, Catholic. Are you saying that only environmental factors independednt from biological evolution can account for biodiversity?”HM

Martin, question: Would you say the overall increase of biodiversity in Sepkoski's graph shown below is or is not associated with of biological evolution? I can agree that an increase in biodiversity is NOT the automatic outcome of biological evolution. We have plenty of evidence on lesser timescales supporting that claim. But I am saying that on a macroscopic timeframe since the Permian Extinction biological evolution has produced a overall increase in biodiversity. No!”HM

I agree”when lesser timescales are inviolved. And I already have said so. Do you think the macro timescale represented in Sepkoski's graph has any bearing on this issue?”HM

Yes, I got it, like a holy shitball smack in my corpus whatever. But I've already agreed to that. Now, please tell me this: If you let loose a population of microorganisms on the surface of a biofriendly Mars, would that population necessarily diversify without Mars' environment changing in any way?My answer: Not necessarily, if you can assume that those microorganisms would have no effect on Mar's enviromnmet. Can you assume that?”HM

Why doesn't it also show that the extant biota and its potential for evolution also favored an increase in biodiversity?”HM

I agree. (But, oops, people who live in glass houses, you know.) With or without evolution?”HM

I do like this one, RADZ. It reminds me of a line from a county-western song: "There ain't no safer sex than the sex I ain't having with you."I think I see your point about randomness...maybe something like the random walk idea. Do I copy you correctly by saying that if a single species of bacteria were to be placed in sterile but fertile environment the only thing it could do evolutionarily would be to diversify. Otherwise it's extinction.”HM

How could this viewed in an evolutionary context? Are you going to tell me that a single that doesn't evolve is engaged in evolution?”HM

Well...yes...if you say so. Why can't it be numbers of genera or families? Paraphrasing what RAZD already said: 'To a single species, there's nothing less diverse than no species at all.' Sure, so long as you agree that if a species neither evolves nor goes extinct has not been engaged in that biological process we call evolution. If this doesn't make sense then I must goin' nuts!”HM

From Message 77: And from your last post: I'm getting dizzy. I better back off my medicine. Probably true, but hard to prove. What people? Most biologist I know of think that biological evolution is a process of change rather than a process of maintianing the staus quo.Back to RADZ's question. Does biological evolution necessarily lead to biodiversity? I think most biologists would have to say 'no'...at least for microscopic timeframes. But what still bothers me is that interesting increase of marine families since the Permian Extinction, shown in Sepkoski's graph in Message 56. Makes me want to get foolish and conclude that the last 245 million years of evolution on Earth have demonstrated a rather steady increase in biodiversity. Just coincidendal with environmental conditions and nothing more? Or an embedded law of macroevolution?One obvious thuth cannot be ignored: No environmental condition remains unchanged for very long, not in geological timesframes.”HM

RADZ, this is a nice challenge to my early morning brain. I apprerciate it. Let me try to deconstruct your argument, if I actually can do it:1. You are saying that macro-biodiversity is purely a consequence of "the ecology and habitability of the planet." I could hardly disagree with this. If Earth's atmosphere, for example, had been hotter 1000 C and made of nothing but mercury vapors I don't think we'd see much of a record of macro-biodiversity.2. And you are saying that because macro-biodiversity "could happen there was a 50-50 change that it would." Here's where I start having trouble. What enables you to assume that macro-biodiversity has a "50-50 chance" of happening? Why not a 60-40 or 99-1 chance of biodiversity happening. Wouldn't that also depend on inherent factors in the biological populations, such as alleles that can be exapted for bio-diversification? Is there no biological component to your argument that allows for integrated participation with ecology and habitability? Didn't cyanobacteria once radically alter Eath's ecology and habitability in ways that accommodated increasing bio-diversity?3. And you say that "meanwhile life muddled along evolving as it went." Does this automatically mean then that biological evolution could not muddle in the direction of macro-diversification? Or does it mean that such muddling is totally limited by environmental conditions...independed of life itself?RADZ, why couldn't that obvious trend of increasing biodiversity in the last 245 million years be the result of an integrated sort of muddling, wherein the biota and their habitats do not change independently but are instead push and pulled by each other in combination?That's the best I can do for this issue. You and CS may be right about the Post hoc ergo propter hoc falacy, which means "After this therefore because of this'." But I stiil don't see how this negates the obvious trend toward macro-diversification on Earth. Not if biota and their habitats historically evolved together, leaving a chicken-and-egg conundrum impossible to separate using your Post hoc ergo propter hoc argument.Did I score any points at all this morning?”HM

Yes, I suppose, if 245 million years of macro-evolution on earth is not enough to test the idea. Maybe what we need is a sterile-but-fertile planet to infect with life to see what happens. I'll bet that bio-diversification happens automatically on that panet, assuming that life can actually survive there and proliferate.”HM

Maybe. Because it could go either way. And there would be matters of ecological capacity to consider. My problem is that I can't tell where the organism ends and the environment begins. And I can't tell the difference between "before" and "after" in your rule: "Post hoc ergo propter hoc falacy, which means "After this therefore because of this'."Catholic, I'll posit one in your favor: ecological succession. Usually ecological succession leads to a decrease in biodiversity, climaxing to stability with fewer extant species.Again, I'm only sinning off from Sepkoski's graph, wherein I find evidence of macro-diversification. Then I'm taking the precarious next step to say that macro-evolution inherently proceeds toward macro-diversification.Side question: Isn't all evidence reducible and refutable by using your "Post hoc ergo propter hoc argument?”HM

Well, then the theory of the expanding universe is a post hoc fallacy, too, since there are no other universes with which to "correlate" (your term) the observation.”HM

If it can be shown that the random walk principle of Cope’s rule is reasonable and verifiable with empirical evidence , I don’t see why that same random-walk principle shouldn’t also apply to evolution, with regards to macroscopic increases in biodiversity.”HM