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Author Topic:   Land Mammal to Whale transition: fossils Part II
NosyNed
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Posts: 8996
From: Canada
Joined: 04-04-2003


Message 256 of 288 (234295)
08-17-2005 10:31 PM
Reply to: Message 255 by RAZD
08-17-2005 10:13 PM


Re: 100,000,000 species?
Have you read over the last day or so of this thread?

This message is a reply to:
 Message 255 by RAZD, posted 08-17-2005 10:13 PM RAZD has replied

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randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 257 of 288 (234336)
08-18-2005 1:09 AM


some facts
Still don't have a lot of time, but here are some facts on Basilosaurus.
1. Not considered a direct ancestor to modern whales which might be worth investigating why not.
An early whale, Basilosaurus is a relative of (but not an ancestor to) modern ceteaceans.
BBC - 404: Not Found
2. Large number of fossils (no specific numbers yet.
This early cetacean (a member of the whale family) is well known from a large number of fossils.
BBC - 404: Not Found
The bones of Basilosaurus cetoides (Owen) and other primitive whales have been found throughout a belt across Louisiana, Mississippi, and Alabama where exposures of Middle and Upper Eocene marine strata, called the Moodys Branch Formation (or Marl) and the Yazoo Clay occur. The vertebrates were so common within some areas of this belt that local residents used them as andirons for fireplaces and blocks to support cabins.
http://geowords.com/lostlinks/f10/3.htm
3. Habitat was warm, shallow waters and seas, swam at or near surface.
Habitat
They lived in the shallow warm seas around the world.
Diet
Basilosaurus were carnivorous, feeding on fish, sharks, molluscs and other cetaceans (whales and dolphins).
Behaviour
Basilosaurus was obviously a predator as fossils have been found with balls of fish and small sharks inside. It was not adapted for deep diving, and would not have been able to hold its breath for very long underwater so it must have swum quite near the surface.
BBC - 404: Not Found
One deduction might be that species that live in shallow waters or are semi-aquatic or live near water and wetland areas prone to flood are more likely to fossilize than species in some other habitats.
I think the general idea is the land mammals that evolved into whales fed on fish and lived in wet areas as well, and that semi-aquatic mammals developed from that. Imo, there is reason here to think that the likelihood of fossilization for all of these species was very similar to Basilosaurus.
I haven't gotten around to finding actual population estimates, but will keep looking.

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AdminNosy
Administrator
Posts: 4754
From: Vancouver, BC, Canada
Joined: 11-11-2003


Message 258 of 288 (234343)
08-18-2005 1:14 AM
Reply to: Message 257 by randman
08-18-2005 1:09 AM


Good work!
A good post, attempting to summarize things.
Also there is an understanding of the need to attempt to quantify things when that is the crux of the discussion.

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 Message 257 by randman, posted 08-18-2005 1:09 AM randman has replied

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 259 of 288 (234683)
08-18-2005 9:23 PM
Reply to: Message 15 by randman
08-09-2005 6:11 PM


Re: replying to fossilzation process here
Just a note:
randman, msg 15, re the spectrum analogy writes:
1. The spectrum is generated by a single quanta of light, correct, and the frequencies do not evolve into another, but the light photon instantly includes all frequencies at once, and is thus the antithesis of evolution.
Is false.
FROM: Photons as light quanta (click)
A photon is a quantum of light. Our picture of light up to this point has been that of a wave, and wave-like characteristics are indeed clearly demonstrated by interference and diffraction effects. However, light is absorbed and emitted one photon at a time. The energy of a photon is related to the frequency of the light wave by Planck's constant:
E = hf
So each quanta has a specific frequency.
This is not to say that the analogy is a good one (there are problems with what represents generations and interelated species of frequencies).
But in order to see the whole spectrum you need to have photons with different energy for the different frequencies.
The reason that the analogy is poor is not related to what randman claimed in any way.

we are limited in our ability to understand
by our ability to understand
RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

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Yaro
Member (Idle past 6495 days)
Posts: 1797
Joined: 07-12-2003


Message 260 of 288 (234698)
08-18-2005 10:57 PM
Reply to: Message 259 by RAZD
08-18-2005 9:23 PM


Enough With the Spectrum thing Already.
Man, way to overanalize an analogy.
Since I am the one who origionaly brought it up, I will explain what I meant by it. It was by no means intended to be a perfect example about how evolution works, nor was I claiming that the spectrum "evolves" or somesuch. I don't give a hoot about the physics of the thing eaither, so leave your quanta and electromagnetism at the door.
I simply meant that the changes between species would look something like the spectrum. Where a gradual gradation leads one color (species) into another. There is no one point where you can say that red becomes red, it's a gradual transition to red.
That's all I ment by that, I'm sorry people have felt it necissary to beat it to death.
This message has been edited by Yaro, 08-19-2005 09:01 AM

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AdminNosy
Administrator
Posts: 4754
From: Vancouver, BC, Canada
Joined: 11-11-2003


Message 261 of 288 (234701)
08-19-2005 12:32 AM
Reply to: Message 260 by Yaro
08-18-2005 10:57 PM


subtitles
Can we all have a look at the subtitles?
Pretty please.

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randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 262 of 288 (234711)
08-19-2005 2:11 AM
Reply to: Message 223 by Percy
08-15-2005 5:51 PM


Re: only 2 issues
Evolutionary change is continuous.
A term ill-defined is useless. In what way do you mean continuous? If you mean it continually occurs, fine, but that adds nothing to the issues here.
If you mean it has a semi-constant rate, that would be interesting to consider?
But really evolution is not characterized by continuous gradualism. As you admit to above, often is thought to occur within smaller groups of a species, for example, and in general proceeds at a strange and varied rate (if macro-evolution occurs at all).
But it's interesting to hear the continuous claim because we don't really see it in the fossil record. We don't, for example, have any cases of large populations of a species undergoing a gradual, total transition into a new species. We don't really see that kind of thing at all.
We see species that must have dozens if not hundreds or thousands of species left out of the evolutionary sequence, and then a whole new species way, way down the line.
But we see tons of the former species, and tons of the later, and rarely anything in between. Assuming the species as a whole evolved, why did a species with very slight changes stop showing up in the fossil record?
Take Basilosaurus. It's fossils were so common that people used them to prop up houses and porches and for andirons. I cannot find any definite estimates but I think tens of thousands of more is likely from the accounts written.
Likewise, we see lots of the current suborders of whales, but we see nothing in between.
So there is evidence that the former forms fossilized and are found in great numbers, but it's immediate predecessor changed so much that it left it's habitat and quit being a good candidate for fossilization?
That appears what evos would have us believe, but what habitat exactly? Whales have an abundance of fossils. Basilosaurus in shallower waters have an abundance of fossils. It seems to me that any other large aquatic mammal that arose in between would likewise have an abundance of fossils.
Is that not reasonable to consider?
But we don't see anything.
Now, I know evos now have come around to admitting Basilosaurys is not a direct ancestor, but the issues remain the same. What we know about large aquatic mammals is they are good candidates for fossilization and to be found in large numbers.
But the theorized ancestors are no where to be found.

This message is a reply to:
 Message 223 by Percy, posted 08-15-2005 5:51 PM Percy has replied

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randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 263 of 288 (234713)
08-19-2005 2:34 AM
Reply to: Message 258 by AdminNosy
08-18-2005 1:14 AM


Re: Good work!
Well, let me add that the creature being so large probably had less numbers than a smaller species. It's range for feeding was a little limited, but maybe there were tons more fish.
It's thus very hard to determine actual numbers. It appears to have lived for 4 million years.
100K species with 25 year lifespans/generational turnover and 4 million years is 16 million, I beleive. Counting partial fossils, fragments of individual species, I really think 100K for an estimate of how many fossils have been found is not a stretch considering they are so common people used them for andirons and to prop up cabins and tons more have been found in Egypt.
So the ration would be one fossil per 160,000 species, and if a 20 year lifespan, then one per 200,000 species, if I did my math right this late at night.
It'd hard to imagine a species not being found with a fossilization rate and discovery this high, and though there should be exceptions, we should, imo, see tons more fossils of the transitionals, especially since they all would have lived near water in a fairly similar habitat in that regard.
Edit to add a little more thinking.
Since whales had to have had evolved fairly quickly, let's estimate some of the transitionals as having a shorter lifespan, thus enabling more generations to evolve and only one million years and in a smaller population size, say 5000.
5000 species with a 10 year span and one million years is 5K times 100K, which is 5 million species. Instead of one per 160K, let's say 1 per 250K.
That is 20 fossils per species for the shorter lived transitionals.
Considering the braching effect and gradual nature of evolution, we should have perhaps thousands of such species for the whole transition and certainly hundreds, and regardless of the estimates, we should literally see every single aspect, every new feature evolving, in the fossil record, not just a few "clues" we intrepret for ToE.
We should see the features morphing, not with big differences, but every major little step along the way.
For example, we may not see some branches as clear, but since at any given time, the nearest relatives have similar features, at least the features or the forms as represented perhaps by family of species, should be evident.
But they are just not there in the fossil record.
This message has been edited by randman, 08-19-2005 02:35 AM
This message has been edited by randman, 08-19-2005 02:45 AM

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 264 of 288 (234738)
08-19-2005 7:31 AM
Reply to: Message 256 by NosyNed
08-17-2005 10:31 PM


Re: 100,000,000 species?
nosyned writes:
Have you read over the last day or so of this thread?
At the time of this response I had read most, but not all, of the thread. I have now done that.
I see no difference to what I have now read and my impression of the trend on this thread at the time of this post: the fossil evidence is rare, the claim that there should be more fossils of transitionals is fraught with misconceptions and erroneous thinking.
The rate of change in species is not constant, but depends on the degree of saturation of the ecosystem as well as the ability of organisms to fit different niches.
I used to have a link (now broken) of an almost complete (like 98%) record of the evolution of forams for over 65 million years.
A section I have saved from the original site is:
Counting both living and extinct animals, about 330 species of planktonic forams have been classified so far, Arnold said. After thorough examinations of marine sediments collected from around the world, micropaleontologists now suspect these are just about all the free-floating forams that ever existed.
By being so small, the fossil shells escaped nature's grinding and crushing forces, which over the eons have in fact destroyed most of the evidence of life on Earth. The extraordinary condition of the shells permits Parker and Arnold to study in detail not only how a whole species developed, but how individuals physiologically developed from birth to adulthood.
"The forams may not be representative of all organisms, but at least in this group we can actually see evolution happening. We can see transitions from one species to another," Parker said.
"We've literally seen hundreds of speciation events," Arnold added. "This allows us to check for patterns, to determine what exactly is going on. We can quickly tell whether something is a recurring phenomenon -- a pattern -- or whether it's just an anomaly.
Adherents of Darwin's theory of gradualism, in which new species slowly branch off from original stock, should be delighted by what the FSU researchers have found. The foram record clearly reveals a robust, highly branched evolutionary tree, complete with Darwin's predicted "dead ends" -- varieties that lead nowhere -- and a profusion of variability in sizes and body shapes. Moreover, transitional forms between species are readily apparent, making it relatively easy to track ancestor species to their descendants.
Note two things:
One of these scientists was a grad student of Gould, and he showed the information to SJG, who then commented that it did look like gradualistic evolution (and not punk-eek) in this species (does not refute it occuring in other species).
The other is that (information not in the above quote) at the 65mya extinction event there was also a massive die-off of the forams, and subsequent rapid speciation diversity until saturation was again achieved at which point it slowed down to the steady state of speciation.
This is randmans biggest problem: the initial evolution into the ocean environment would be similar in nature to the post-extinction unsaturated environment, while extant whales are living in a saturated environment, and comparing them is fraught with several logical errors.
ps -- if anyone can provide an updated link to the work by Parker and Arnold it would be appreciated.

we are limited in our ability to understand
by our ability to understand
RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

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 Message 256 by NosyNed, posted 08-17-2005 10:31 PM NosyNed has not replied

Replies to this message:
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NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 265 of 288 (234765)
08-19-2005 9:20 AM
Reply to: Message 262 by randman
08-19-2005 2:11 AM


continuous evolution
But it's interesting to hear the continuous claim because we don't really see it in the fossil record. We don't, for example, have any cases of large populations of a species undergoing a gradual, total transition into a new species. We don't really see that kind of thing at all.
If there are, in fact, some examples of exactly this will you get off this mistaken idea?
We see species that must have dozens if not hundreds or thousands of species left out of the evolutionary sequence, and then a whole new species way, way down the line.
You have never given a good reason why there should be such large numbers of intermediate species. You have ignored a number of reasons given to you as to why we might not. There are not 10,000's of Basilosaurus fossils.
So there is evidence that the former forms fossilized and are found in great numbers, but it's immediate predecessor changed so much that it left it's habitat and quit being a good candidate for fossilization?
You have been given a number of reasons for this. Will you show how they don't apply in the case you are talking about? You seem to have trouble dealing with more than one simple thing at a time.
You almost answer your own question in the next paragraph. How many Basilosaurus fossils do we find in the habitats that current (and not so distant) whales occupy?

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Percy
Member
Posts: 22388
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 266 of 288 (234772)
08-19-2005 9:54 AM
Reply to: Message 262 by randman
08-19-2005 2:11 AM


Re: only 2 issues
randman writes:
Evolutionary change is continuous.
A term ill-defined is useless. In what way do you mean continuous? If you mean it continually occurs, fine, but that adds nothing to the issues here.
I already described this in some detail in Message 123. You haven't responded yet. Why don't you give it a read and let me know if you have any questions.
But really evolution is not characterized by continuous gradualism.
It cannot be anything but. Each offspring is only very slightly different from its parents. Evolutionary change cannot proceed in steps any larger than the difference between parents and child.
It becomes obvious that evolutionary change cannot proceed in species-sized steps when you ask who an offspring that was a new species would breed with. Obviously there would be no available mates, and the new species would die out at the end of the life of its first member. So we know just by this simple logic alone that evolution must proceed in steps that are smaller than the size of a species.
But genetic information tells us that the change is very tiny, and I described this a little in the other thread. This is why DNA testing can determine parentage, because the genetic distance between parent and child is so small.
As you admit to above, often is thought to occur within smaller groups of a species, for example, and in general proceeds at a strange and varied rate (if macro-evolution occurs at all).
It proceeds at a varied rate, but I certainly wouldnn't call it "strange".
If micro-evolution is possible then macro-evolution is inevitable. Let's say you're going to take a trip, and you're going to do it on foot. You're going to string together many micro-trips of one step each. After enough micro-trips you discover you're in another city and that you've accomplished a macro-trip. At what point did you complete sufficient micro-trips to be considered a macro-trip. For the purposes of this analogy, we could call it a macro-trip when you reach the next city.
So we could consider macro-evolution as occurring when a species reaches the next species, meaning that it can no longer interbreed with the original species. And it achieved this macro-evolution with many small micro-evolutionary steps, each one accomplished through a single reproductive event.
But it's interesting to hear the continuous claim because we don't really see it in the fossil record. We don't, for example, have any cases of large populations of a species undergoing a gradual, total transition into a new species. We don't really see that kind of thing at all.
Yes, we know we don't find large populations leaving a record of gradual change. We've explained many times now why large populations tend to be stable, and I'm running out of analogies for you. We've explained that small changes are swamped by large populations but can have a significant impact in a small population. I myself have used a couple analogies. I've used the analogy of shouting in a small quiet room, which would get everyone's attention, versus at a rock concert, which would be heard by few. I've used throwing a rock into the ocean, where it would have little effect, versus a mud puddle, where it would have a huge effect. If you can explain your objections to these explanations, instead of repeating your original objections, then we can offer clarifications and the discussion can move forward.
--Percy

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 Message 262 by randman, posted 08-19-2005 2:11 AM randman has replied

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randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 267 of 288 (234803)
08-19-2005 11:20 AM
Reply to: Message 266 by Percy
08-19-2005 9:54 AM


Re: only 2 issues
Percy, neither I nor anyone has claimed evolution is not gradual in one sense, that the adapted changes would be very small, which is why I think there should be more evidence of fossilization.
My point, and something you seem to dodge every time, is that the species as a whole does not exhibit gradual change, for the very reasons you point out.
So what we have is a branching effect, and from the species as a whole, it is not a continuous change. Sometimes, species don't evolve for example.
There is selective and varied theorized evolutionfor groups that create a varied branching effect as I showed with horse evolution.
Frankly, I don't see why this is such a hard concept for you and some others to grasp, and ironically, you seem even say the same thing at times when you admit that large species don't typically change because the changes would be swallowed up, but rather smaller groups exhibit changes.
Now, the point for this area of discussion is that one would not expect for this new group, considering how evolution "per that group" is gradual and not characterized by "spurts, stops, branches, etc,...", that the new group would by the gradual nature of the change only exhibit very small changes from the parent species.
So examining the level of changes needed to transition a land mammal to a whale, one can posit a great number of such "speciation events" defined as new species splitting off and developing, and considering the branching effect that usually takes place, once again see the horse evolutionary story which you dismiss but I still see no reason why, we should expect in the thousands of transitional species to have arisen in this transition.
Now, you and Ned may not like my data or reasoning, but at least I have offerred some, and I see no good reason to reject any of it.
You yourself say the evolutionary changes would be very small and gradual, but just add up over time.
You admit they would need to occur within a smaller population and not the larger population as a whole.
Even with a far, far smaller level of change required, we see a branching effect via horse evolution. There is absolutely no reason to not expect therefore that per the level of change in horse evolution, we see a similar level of branching.
You say the horse example is not germane?
Then what is, percy?
What, if anything, from the fossil record could convince you that land mammal to whale evolution should follow the normal theoritical route claimed for other species?
Do you really believe horse habitats were more varied than the land mammal to whale transition, as you seem to have offered as a reason to reject the use of horse evolution?
It looks to me you guys just don't want to accept the data and analysis out of mere prejudice.

This message is a reply to:
 Message 266 by Percy, posted 08-19-2005 9:54 AM Percy has replied

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randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 268 of 288 (234811)
08-19-2005 11:36 AM
Reply to: Message 264 by RAZD
08-19-2005 7:31 AM


Re: 100,000,000 species?
That's an explanation for why there could be rapid evolution followed by much slower evolution, but that's not an explanation for why we don't see the fossils.

This message is a reply to:
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Percy
Member
Posts: 22388
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 269 of 288 (234837)
08-19-2005 1:20 PM
Reply to: Message 267 by randman
08-19-2005 11:20 AM


Re: only 2 issues
randman writes:
Percy, neither I nor anyone has claimed evolution is not gradual in one sense,...
So you accept that evolution does not proceed in sudden species-sized steps? I just want to be sure we've got this misunderstanding squared away now, because I'm surprised to see you say this after the way you rejected "spectrum" as an analogy and called "continuous" poor terminology.
...that the adapted changes would be very small,...
I think you mean adaptive changes. While the changes will be very small, they won't necessarily be adaptive. Changes at the genetic level, either as allele permutations or as mutations, could have any of these results:
  • No expression in the organism whatsoever. The genetic change has no effect.
  • An adaptive improvement for the organism in its ecological niche.
  • A neutral change relative to its ecological niche.
  • A maladpative change relative to its ecological niche.
...which is why I think there should be more evidence of fossilization.
Thank you for restating your premature conclusions for the umpteenth time. No randman post is complete without them!
My point, and something you seem to dodge every time, is that the species as a whole does not exhibit gradual change, for the very reasons you point out.
I believe you that you are perceiving it this way, but could you please believe us that it is our perception that you are failing to make some key connections.
The issue is not being dodged. It has been explained to you over and over that small populations under environmental stress are most likely to change in relatively short time periods (thousands of years) and are least likely to be preserved in the fossil record.
Let's say that species A lived 5 million years with an average population at any given time of about a million creatures. Multiply 5 millions years by 1 million creatures and you get 5 trillion creature-years.
Let's say that species B lived 10,000 years with an average population size of 10,000 creatures yielding 10 billion creature-years.
This means that species B is only .5% as likely as species A to leave behind fossils. For every 1000 fossils of species A we find, we can only expect to find 2 of species B.
But, as I explained before, there are many other factors at work. This is from Message 111, to which you also haven't replied:
Percy writes:
There are many possibilities, but I'm just going to mention a few:
  • Species A was decimated by some catastophe, and the survivors evolved over a relatively short time period into species B, which was marginally successful, and then into species C in a small geographical region leaving some fossil remains behind, but we haven't discovered them yet because this region is currently buried under a mile of geological strata. Species C was very successful and repopulated the area formerly occupied by species A.
  • Now imagine the same scenario, except this time the survivors of species A are in small geographical region off a continental shelf. The same thing happens as before, but this time instead of the region being buried deep beneath geological strata, the region subducts under the continent and is gone forever, including all fossils of species B.
  • Now imagine the same scenario, except this time species B doesn't happen to occupy a region where fossilization is likely. No fossils of species B exist or ever existed.
  • Now a different scenario. In this one it is simply that the intuition of paleontologists are wrong in this case. Because of environmental pressures, species A or a cousin evolved in gradual (but short geologically) stages into species C, never pausing for any extended period at a particular stage of development. This happened quickly enough that too few individuals were ever fossilized to make discovery likely.
  • Just for completeness and not because I think it a realistic possibility, species A somehow became species B all at once in a sudden jump.
  • And lastly a scenario I consider completely unscientific, species A went extinct and species B was created by some intelligent agent.
If you reject these then you have to explain why. Merely repeating over and over again that "there should be more transitionals" (sic) provides no information about why you continue to believe this.
There is selective and varied theorized evolution for groups that create a varied branching effect as I showed with horse evolution.
Reaching conclusions about the nature of speciation from horse evolution is valid.
Concluding that all evolutionary series should be as well represented in the fossil record as the horse is invalid. I pointed this out to you once before in Message 193:
Percy writes:
  • There is no way to know if horse evolution is typical. Only by examining the evolution of many different species could we arrive at some kind of relationship or general rule for the number of species expected to be represented over time.
  • We can't know how complete our record of horse evolution is. It may be very complete. On the other hand, 57 additional varieties of horse may have evolved and left fossils in a region of the American west that has since eroded away and no longer exists. Or they may be buried in geological strata that are still buried a mile underground. We can't know what's in the missing or unreachable strata. This is part of why the fossil record is so serendipitous, so unpredictable in what gets preserved or discovered.
  • Speciation rates are a function of the stability of ecological niches. A stable ecological niche should not produce much, if any, speciation. Rapidly changing niches should cause a great deal of speciation. In making comparisons between horse and whale you have to factor in the relative rates of change of their ecological environments.
In addition, the horse fossil record is cited so frequently because it is so exceptionally complete. If it weren't so exceptional it wouldn't be cited so often. You cannot expect the average to approach the exceptional.
So examining the level of changes needed to transition a land mammal to a whale, one can posit a great number of such "speciation events" defined as new species splitting off and developing, and considering the branching effect that usually takes place, once again see the horse evolutionary story which you dismiss...
I did not dismiss the horse evolutionary story. I dismissed your drawing conclusions about whale representation in the fossil record based upon horse representation in the fossil record. Your supporting argument so far has been, "They're both mammals."
... but I still see no reason why, we should expect in the thousands of transitional species to have arisen in this transition.
I see no reason why, either. Clearly you don't understand what I was saying if you think I was saying this, but you didn't quote anything specific that I said, so I can't guess what led you to think this.
Perhaps it was where I was speaking of evolution as a continuum of gradual change? If so, keep in mind the example of ring species. There can still be fairly significant change while maintaining significant gene flow between two distinctly different populations. Keep in mind the analogy of micro-trips and macro-trips. Just as each step is not a journey to a new city, each small evolutionary change does not create a new species.
Now, you and Ned may not like my data or reasoning, but at least I have offerred some, and I see no good reason to reject any of it.
I think Nosy and I are probably pretty much in agreement that you seem to keep repeating your conclusions with no apparent line of reasoning. You've made some "if this, then that" statements, but it's not logic we can follow. It all seems like "It's too hot outside, so I think we must be out of forks" type of reasoning. Our reaction is often, "Why does he think one follows from the other?"
What, if anything, from the fossil record could convince you that land mammal to whale evolution should follow the normal theoritical route claimed for other species?
I never said it shouldn't. I said you shouldn't expect to find the fossil records of other groups to be as complete as for the horse.
Do you really believe horse habitats were more varied than the land mammal to whale transition, as you seem to have offered as a reason to reject the use of horse evolution?
It's good that you're repeating back to me what you think I said, because it is clear you often misunderstand what I'm saying. I would never have said that horse habitats were more varied than for whales. What I believe, and what I likely said if I said anything at all (once again, you don't quote anything, so I can't know what passage from me you're misinterpreting) is that it isn't possible to know how many habitats were involved. The fossil record is serendipitous and incomplete.
It looks to me you guys just don't want to accept the data and analysis out of mere prejudice.
I think you should continue to try to avoid drawing conclusions until you at least get an indication from those you're debating with that you've got an accurate understanding of what they're saying. Most of what you say you think I said I don't recognize.
--Percy

This message is a reply to:
 Message 267 by randman, posted 08-19-2005 11:20 AM randman has replied

Replies to this message:
 Message 270 by randman, posted 08-19-2005 1:43 PM Percy has replied
 Message 271 by randman, posted 08-19-2005 1:44 PM Percy has not replied

  
randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 270 of 288 (234847)
08-19-2005 1:43 PM
Reply to: Message 269 by Percy
08-19-2005 1:20 PM


Re: only 2 issues
Percy, we're not going to get anywhere until you guys deal with some issues.
First, the spectrum analogy is dumb because it is a straight-line progression, i.e..no branches.
Why is that so hard for to grasp, after YOU'VE been told so many times?
The issue is not being dodged. It has been explained to you over and over that small populations under environmental stress are most likely to change in relatively short time periods (thousands of years) and are least likely to be preserved in the fossil record.
Where did the small population come from? This is offensive to have to debate this after so much time, but let's get this clear, evolution is not just a straight-line progression, a linear single group path of small populations. We have proof some populations are in fact quite large.
Got it?
In terms of your analysis, the error in your logic is that while it is true certain changes affect the likelihood of speciation, over very long geologic time periods, these changes are averaged out. Considering the aquatic habitat that whale evolution would have occurred in, there is very little reason to think that most of these transitions would not have left fossils that we discovered by now.
Listing all the ways an individual species could not escape fossilization does little to advance your argument unless you are arguing that this evolutionary process somehow magically created only a handful of larfer populations via the incredible distance of morphological and behavioural changes that would need to be adapted.
Basically, you are then arguing that the vast majority of the transitionals were barely functional in terms of survival and stayed extremely small in numbers, but kept on morphing right from land mammals to whales.
It's absurd frankly, and you have offer not one whit of quantitative analysis to back up your just-so story here. I can imagine a reasonably likelihood of an exception to fossilization as you posit, even though it's just based on imagination and not factual record, but for one or two speciation events yielding new smaller grouped species, that can be likely, but you are essentially claiming this had to have happened for 90% plus of the process since literally the vast majority of changes are not seen developing. The stages are not seen in the fossil record.
That's straining the data on your part, imo, to fit into a preconceived and previously held belief, which is why I think of ToE as more faith-based than science based.

This message is a reply to:
 Message 269 by Percy, posted 08-19-2005 1:20 PM Percy has replied

Replies to this message:
 Message 273 by Percy, posted 08-19-2005 3:16 PM randman has not replied
 Message 275 by nwr, posted 08-19-2005 8:39 PM randman has not replied

  
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