"...Darwin was no dummy. He answered most of the concerns himself ... in the same book where he first gave them voice. In short, the responses take the following form:" (Martin 2003)
“...number of points ... taken together, seem to me to explain the systematic discontinuities of records of the origin of higher categories and to make their interpretation as due to saltation entirely untenable. ...
1. There is time corresponding with the unrecorded sequences; the discontinuities follow time gaps.
2. The discontinuities are not absolute; they may be very slight or almost nominal, and isolated finds of fossils of intermediate type may occur in them.
3. Gaps comparable in length are known which certainly had occupants even though these do not appear in the fossil record.
4. The origin-sequences are often of such length that under conditions of paleontological sampling it is almost impossible for their record to be continuous.
5. Chances of discovery of transitional types are often reduced by the fact that they moved between quite different ecological conditions.
6. Relatively small populations were often involved.
7. The rate of evolution was often relatively fast and fewer inviduals occurred per structural stage than in average well-recorded sequences.
8. The transitions were in restricted geographic regions and not always in the same region throughout any one transition."
(Simpson 1953)
"In addition to quantum or punctuational evolution, there is another important evolutionary process which serves to explain how it comes about that, in many cases, transitional forms will never be found between one genus or species and another. This developmental process is known as neoteny or paedomorphosis ...
A consequence of this mode of evolution would be that the preliminary steps in the evolution of succesful major groups would take place in young stages, which would be unlikely to be preserved as fossils, and would thus remain forever unknown, and as de Beer concluded: "The sudden appearance of new types, and the apparent gaps in phylogenetic series, receive a logical explanation on these lines." (Montagu 1984)
"Absence of appropriate sediments. Most of the earth's ancient sediment is gone...
Much of the Earth's sediments are covered by vegetation and water. ...
Minimal time spent searching the rocks for fossils by a limited number of people; paleontology is not a field that receives much funding as compared with, for example, cancer research.
...
The absence of transitional forms in the fossil record has partly been the result of an old typological concept in which paleontologists were more concerned with naming new species than determining their relationships ...
punctuated equilibrium hypothesis ... (Martin 2003)
"In many instances, transitional inviduals exist but are not reported explicitly as evolutionary lineages, for several reasons. Fully documenting such complete sequences is rather expensive in both research effort and publication cost; thus many remain unpublished (Berry & Boucot, 1970, p. 30-31). Moreover, the practicing paleontologist sees little need to repeatedly reprove well-established concepts, especially when his primary concern is with other matters such as biostratigraphic dating (Berry, 1960, p. 9)" (Cuffey 1984)
"Rudwick (1972) has argued that Darwin's emphasis on the supposed incompleteness of the fossil record may have discouraged paleontologists to collect fossils in closely spaced stratigraphic intervals to document transitional evolution." (Levington 2001)
"We argue that the existence of species as distinct and relatively homogeneous groupings of individuals is a consequence of the nonlinear dynamics inherent in sexual reproduction. This approach provides an answer to two interrelated problems which Darwin posed and tried to solve. Why are there missing links (i.e. gaps) between species in habitat space, and why are there missing links between species in time as evidenced in the fossil record?" (Bernstein et al. 1985)
Referenssit:
1.Genetics, Paleontology, and Macroevolution Jeffrey S. Levington Cambridge University Press 2001
2.The Major Features of Evolution George Gaylord Simpson Columbia University Press, New York 1953
3.Missing Links: Evolutionary Concepts and Transitions Through Time Robert A. Martin Jones & Bartlett Publishers 2003
4.Science and Creationism Ashley Montagu Oxford University Press 1984
5.Sex and the emergence of species. Bernstein H, Byerly HC, Hopf FA, Michod RE. J Theor Biol. 1985 Dec 21;117(4):665-90.
“...number of points ... taken together, seem to me to explain the systematic discontinuities of records of the origin of higher categories and to make their interpretation as due to saltation entirely untenable. ...
1. There is time corresponding with the unrecorded sequences; the discontinuities follow time gaps.
2. The discontinuities are not absolute; they may be very slight or almost nominal, and isolated finds of fossils of intermediate type may occur in them.
3. Gaps comparable in length are known which certainly had occupants even though these do not appear in the fossil record.
4. The origin-sequences are often of such length that under conditions of paleontological sampling it is almost impossible for their record to be continuous.
5. Chances of discovery of transitional types are often reduced by the fact that they moved between quite different ecological conditions.
6. Relatively small populations were often involved.
7. The rate of evolution was often relatively fast and fewer inviduals occurred per structural stage than in average well-recorded sequences.
8. The transitions were in restricted geographic regions and not always in the same region throughout any one transition."
(Simpson 1953)
"In addition to quantum or punctuational evolution, there is another important evolutionary process which serves to explain how it comes about that, in many cases, transitional forms will never be found between one genus or species and another. This developmental process is known as neoteny or paedomorphosis ...
A consequence of this mode of evolution would be that the preliminary steps in the evolution of succesful major groups would take place in young stages, which would be unlikely to be preserved as fossils, and would thus remain forever unknown, and as de Beer concluded: "The sudden appearance of new types, and the apparent gaps in phylogenetic series, receive a logical explanation on these lines." (Montagu 1984)
"Absence of appropriate sediments. Most of the earth's ancient sediment is gone...
Much of the Earth's sediments are covered by vegetation and water. ...
Minimal time spent searching the rocks for fossils by a limited number of people; paleontology is not a field that receives much funding as compared with, for example, cancer research.
...
The absence of transitional forms in the fossil record has partly been the result of an old typological concept in which paleontologists were more concerned with naming new species than determining their relationships ...
punctuated equilibrium hypothesis ... (Martin 2003)
"In many instances, transitional inviduals exist but are not reported explicitly as evolutionary lineages, for several reasons. Fully documenting such complete sequences is rather expensive in both research effort and publication cost; thus many remain unpublished (Berry & Boucot, 1970, p. 30-31). Moreover, the practicing paleontologist sees little need to repeatedly reprove well-established concepts, especially when his primary concern is with other matters such as biostratigraphic dating (Berry, 1960, p. 9)" (Cuffey 1984)
"Rudwick (1972) has argued that Darwin's emphasis on the supposed incompleteness of the fossil record may have discouraged paleontologists to collect fossils in closely spaced stratigraphic intervals to document transitional evolution." (Levington 2001)
"We argue that the existence of species as distinct and relatively homogeneous groupings of individuals is a consequence of the nonlinear dynamics inherent in sexual reproduction. This approach provides an answer to two interrelated problems which Darwin posed and tried to solve. Why are there missing links (i.e. gaps) between species in habitat space, and why are there missing links between species in time as evidenced in the fossil record?" (Bernstein et al. 1985)
Referenssit:
1.Genetics, Paleontology, and Macroevolution Jeffrey S. Levington Cambridge University Press 2001
2.The Major Features of Evolution George Gaylord Simpson Columbia University Press, New York 1953
3.Missing Links: Evolutionary Concepts and Transitions Through Time Robert A. Martin Jones & Bartlett Publishers 2003
4.Science and Creationism Ashley Montagu Oxford University Press 1984
5.Sex and the emergence of species. Bernstein H, Byerly HC, Hopf FA, Michod RE. J Theor Biol. 1985 Dec 21;117(4):665-90.
Vastaukset 2
Vanhimmat
have not been found or they all have turned to ashes. Plus other elements...
I'm only 50 years old, and I haven't been able to find evidence, from photo-albums for example, that I'm the same person as the one my mother gave birth to....
With such facts in mind, it seems appropriate to me to launch the question to the creationists of the forum : do these factors serve to explain the absence (relative rarity, that is) of transitional forms in the fossil record?
Why - Why not?