10 Nov 1997 07:36:10 -0600 you replied to my reply,
>>This is exactly what would be expected if the Miocene to Recent fossil
>>record represents speciation since the Flood. With all that environmental
>>change, much "descent with modification", through "survival of the fittest"
>>in each area would be necessary. This is reality in our fallen ecology.
>
>So in other words you do believe in evolution.
Obviously there has been descent with modification. And evolution (which
means opening out or unfolding) would be an excellent word for in, except
that in our culture it connotes "molecules to man" which is an extreme
extrapolation of the observable data. So I stay with the words adaptation
or speciation or descent with modification, but not evolution.
In fact you believe evolution
>is much more rapid than even the evolutionists do. You are having all this
>change all these speciations occur in about 5,000 years. Since there are
>4280 living species, which don't appear as fossils, and thus did not live in
>the preflood world, this means you believe that approximately 1 species
>evolved per year over the past 5000 years. But since most of these species
>of were in existence and unchanged 2000 years ago, (from historical
>records), this means that all this evolution must have occured in only 3000
>years ago. But at least for falcons, crocodiles, cats, lions, leopards,
>dogs, jackals etc we know that they were in existence unchanged in 3000 B.C.
>when the Egyptian civilization was founded. Thus all this evolution must
>have occurred prior to that. Why did all this very rapid speciation cease
>for the past 3000 years. I mean evolution was going great guns, creating
>species after species of horse, canid etc and now during our life time I
>don't get to see this happen as quickly any more.
>
Right. There is still some speciation going on, but not at rates anything
like this. Viewing this mostly paleobotanically (but remembering the
animals too), I see a tremendous burgeoning of speciation in the immediate
postflood decades, when populations were spreading into wide open niches.
The resulting forms are more specialized, with less adaptability. To take
an example among the animals, rabbits that have survived in dry places as
deserts have spread, and rabbits which have adapted to arctic conditions
may no longer be able to interbreed, and may no longer be able to adapt to
as much environmental change now. It is well known that specialized forms
have less adaptability.
>Doesn't this seem inconsistent to you?
>
It could be. But conditions in the past were very different from
conditions in the present. The fossil record shows relatively mild
conditons even to high latitudes in the past, and much more varied and
stressful conditions in the present world, requiring more specialization.
>>
>>>
>>>So while we may bump into limits over a 1000 year period, it might not be
>>>there if given more time.
>>
>>On the other hand, if the stress of that much change pushed the limits of
>>genetic versatility in each of the kinds, they might become progressively
>>less able to change any more, and there would be many extinctions.
>
>But I thought you had said that 4 generation was about the limit to any
>change that could occur.
I heard that some plant breeders say that today 4 generations pushes the
limits.
It may have been more generations in the past. And there were many
extinctions.
Remember you have to have all horse kind evolve
>from a single horse kind and that required major chromosomal mutations.
>
>Burchell's zebras have 44 chromosomes, some 45 chromosomes due to a
>chromosome that brokein two.
>
>Most donkeys have 62 chromosomes but one fertile female was found with 63
>
>Persian onagers can have 55 or 56 chromosomes;
>kulans can have 54 or 55; and
>kiangs can have 55 or 56.
>Equus Caballos 64 chromosomes
>Przewalski's horse has 66 chromosomes
>
>Look at what you need to do with the Canids evolution:
>
>chromosomes canidae family
>Wolf-like canids common name geographic range 2n
>small (5-10 kg
>
>Canis aureus Golden jackal Old World 78
>Canis adustus Side-striped jackal SubSahara Africa 78
>Canis mesomelas Black-backed jackal SubSahara Africa 78
>
>Large (12-30 kg)
>
>Canis simensis Simien jackal Ethiopia 78
>Canis lupus Gray wolf Holarctic 78
>Canis latrans Coyote North America 78
>Canis rufus Red wolf Southern U.S. 78
>Canis alpinus Dhole Asia 78
>Lycaon pictus African Wild Dog Subsaharan africa 78
>
>South American Canids
>
>Speothos venaticus Bushdog Ne S. America 74
>Lycalopex vetulus Hoary fox Ne S. America 74
>Cerdocyon thous Crab-eating fox Ne S. America 74
>Chrysocyon brachyurus Manes wolf Ne S. America 76
>
>Red fox-like canids
>
>Vulpes velox Kit fox Western U.S. 50
>Vulpes vulpes Red fox Old and new world 36
>Vulpes chama Cape fox Southern Africa not given
>Alopex lagopus Arctic fox Holarctic 50
>Fennecus zerda Fennec fox Sahara 64
>
>other canids
>
>Otocyon megalotis Bat-eared fox Subsaharan Africa 72
>Uocyon cinereoargenteus Gray fox North America 66
>Nycteruetes procyonoides Raccon dog Japan, China 42
>
>Robert K. Wayne, "Molecular evolution of the dog family," TRENDS IN GENETICS,
>9:6,June 1993, p 219
>
Thank you for the list and the reference. I remember pouring over pictures
of the chromosomes of various animals years ago. You can guess which ones
split or fused. Do you have a reference that shows the pictures?
In some genera of plants, chromosome numbers vary even more widely.
Chromosome breakage, fusion, etc. is to be expected as populations diverge.
>What you are proposing is that all this chromosomal rearrangement took place
>almost instantaneously after the flood. We know most of the foxes, jackals,
>dogs and wolves were intact during the Egyptian Dynasties. But strangely, it
>doesn't happen as rapidly anymore. What happened?
>
Some of the genetic "get up and go" got up and went. The world is getting old.
>>
>>>
>>>The number of extinct species found in the various epochs of the
>>>Tertiary are:
>>>
>>>Pleistocene 786
>>>Pliocene 1119
>>>Miocene 2988
>>>Oligocene 1282
>>>Eocene 1819
>>>Paleocene 604
>>>
>>
>>I find this fascinating. Thank you, again! What is the reference?
>
>Donald E. Savage and Donald E. Russell, Mammalian Paleofaunas of the World.
>
>I had to compile the information
>
>>
>>Look at the array of numbers there -- the most extinctions in the Miocene,
>>with fewer on each side (the Oligocene is low because it is "short" (a
>>thinner sequence) (Gk. oligo = little or few) and the Eocene is higher
>>because it is "long" (thicker sequences).
>>
>That is not the etymology of Oligocene and Eocene. Oligo means few but it
>meant few living species of shellfish. Eo means "dawn"
>
Sorry. I had the impression that the Eocene was much longer than the
Oligocene (tho I didn't mean "Eo" meant "long"!), but now I see it is
designated as about 57-37= 20 million years, compared with 37-23= 14. Not
as different as I thought.
>
>>>From the paleobotanical viewpoint, the Miocene is the period when the
>>extreme diversity of the Eocene (which could be interpreted as massive
>>resprouting
>>after the floodwaters receded) starts to tend toward the present
>>biogeography, with what I call "differential survival" (some plant kinds
>>dying out in one area but surviving in another, while others survive and
>>speciate in other areas...).
>>
>>With the Pliocene cooling and drying there was the spread of grasslands
>>which profoundly affected the speciation of ungulates, etc., and after that
>>there was less (but still some) extinction of vertebrates.
>
>How many years long do you envision each of the periods to be?
>>
>>
I don't know. I believe glaciation came less than 1000 years after the Flood.
In a few centuries a lot of migration and extinction can take place, with
adaptation producing varieties that would paleontologically be called
species.
>>
>>>The average species is only found in one of these epochs. This implies that
>>>the fauna almost entirely turns over with the passing of each epoch. This
>>>is another difficulty for the global flood--explaining why different forms
>>>are deposited in the various layers, inspite of the fact that most
>>>ecozones are
>>>represented in each epoch.
>>
>>In the Tertiary, I expect a lot of "turnover", as I noted above. Ernst
>>Mayr's conditions for optimum speciation (small population size, low
>>predation, low competition, open niches, etc.) would be exactly fulfilled
>>in the immediate postflood environment.
>
>But we don't find small population sizes in many of the species. We find
>lots of fossils.
Yes - like the vast Miocene beds of rhino skeletons, in Agate Springs,
Nebraska.
That means a lot of reproduction -- a real burgeoning. I would expect the
smaller populations in earlier strata.
In the Eocene, there are some abundant fossils, like the turtles in the
Bridger.
Many of those are found buried upside down. Possibly dead before
emplacement. "Immediate postflood" conditions may be at different levels in
different areas.
Has anyone done a study of population density up through the (correlated)
strata for various taxa? It might be very interesting, especially now
that paleontologists are more tuned into taphonomy.
>
>
>>>Doesn't this mean that life has changed? I see only two possibilities.
>>>Evolution or progressive creation that mimics the pattern of evolution
>>>
>>
>>Sure, life has changed. But there are more than those two possibilites.
>
>I guess one could include rapid, young-earth approved evolution which we
>rename as microevolution.
>
or simply adaptation.
I appreciate the dialog.
May the Lord bless you.
Karen