Report of the Committee on Paleoecology, 1935-1936: Presented at the Annual Meeting of the Division of Geology and Geography, National Research Council, May 2, 1936 (1936) / Chapter Skim
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Paleoecology of the Vertebrates - E. C. Case
Paleoecology of the Vertebrates - E. C. Case
Pages 10-21
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From page 10... ...
Morphology The utterly fallacious idea that frorc a single bone tho expert can restore a complete skeleton lingers with as much persistence and with as disastrous results as does tho fallacious Biogonotic lav:. In both the
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From page 11... ...
The hooves and characteristic teeth of a grazing or browsing animal are commonly associated and from these and less obvious characters of the skeleton the paleoecologist may infer broad grass lands, sparsely watorod, and onomios that demand speod for oscapo, things to be checked by the remains of associated animals and by the nature of the matrix in vfoich the skeleton is entombed. For exceptions to such correlation one has but to recall Moropus or Agriochoerus in both of which the teeth, limbs and a::ial skeleton suggest a grazing or browsing ungulate but in which the toes terminate in efficient claws.
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From page 12... ...
Petrefuction requires burial under water or in water-bearing layers and for arboreal, aerial, dry land, and any but benthonic forms of aquatic life, this requires that bones found petrified roust have boon transported from their natural habitat to a region of radically different conditions. The transportation of a.
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From page 13... ...
Much futile discussion has gathered around just this point - the fish were fresh-water forms washed out to sea by flood either before or after death, were marine forms killed by sudden influx of fresh-water, were estuarine and destroyed by an untoward degree of salt concentration in the water. Knowing as we :do how closely some fish are restricted to a definite salt content in the water ond how tolerant are others, it is evident that we are here dealing with a problem of physiological response, not reflected in structure, which at the present is beyond the possibility of solution.
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From page 14... ...
In fossiliferous areas or localities such as the Big Badlands of South Dakota, the Agate Spring bone beds of Nebraska, or the bone beds at Pikermi in Greece, the nature of the bones indicates preservation in or near the place of death. In the growing river flood-plain of Oligocene time, which is BOW the Big Badlands, the carcasses of the animals commonly found burial in the river beds or mud holes which were an integral part of their habitat.
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From page 15... ...
The progress of the plant world to modern types has consistently outdistanced the animal world. The modern deciduous trees shaded the Mesozoic reptiles in their later days.
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From page 16... ...
Normally minute animals may have giant species or individuals, as well as normally much larger animals. It has been noticed and commented upon that in giant forms of vertebrates the seat of the pituitary gland is relatively enlarged, even to monstrous size.
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From page 17... ...
The assemblage of incidents and suggestions in the preceding pages is not, and is not intended to be, even approximately, definitive or exhaustive but merely serves to direct attention to a few of 1he innumerable factors of paleoecology which influence life. • The Matrix .For the vast majority of land animals and for all fish except benthonic forms, the matrix of entombment is radically different from the normal environment of the animal.
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From page 18... ...
The color has been explained by original deposition of ferric oxide, by secondary infiltration, by dehydration due to the pressure of incumbent beds, by change in ground water level. It has even been assxened that red beds mean some.definite condition and that red beds are uniformly red, instead of yellow, green, blue, purple and all intermediate shades.
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From page 19... ...
It is interesting to note that most of the vertebrates of the Upper Triassic in tie western part of the United States are found in river, delta or pool deposits; every implication of these deposits is that they were derived from an arid land. For the Stegocephalia and the Phytosaurs, which latter are so crocodile-like in structure as to leave little doubt of their habitat, the deposits and the animals arc well correlated but it is a little difficult to picture the adjacent lands, because the remains of terrestrial animals and plants are so limited.
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From page 20... ...
In the Museum of Paleontology of the University of Michigan there is a collection of many Stegoceplialisn skulls and other closely intermingled bones recovered from Triassic deposits in western Texas. The skulls and the clavicles amd interclavicles showing peculiarly sharp and intricate sculpture, the needle-like teeth, are perfect and the paper thin edges of certain bones are intact; they are as perfectly preserved as any fossil material the author has seen.
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From page 21... ...
- 21 but one of many necessary tools. As written above, the fission is inevitable, tiie two schools must be prepared to afford mutual criticism and aid, the paleontologist in training must be prepared to know the elements of both phases of the work, but choose one for intensive training - and provision must be made for such intensive training.
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