Authors Schad W. Institution Institut fur Evolutionsbiologie und Morphologie, Universitat

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Authors Schad W. Institution Institut fur Evolutionsbiologie und Morphologie, Universitat Witten/Herdecke, Germany. Title Heterochronical patterns of evolution in the transitional stages of vertebrate classes. Source Acta Biotheoretica. 41(4):383-9, 1993 Dec. Abstract Transitional forms of the recent classes of vertebrates are only known in paleontology. The well described examples are: Eusthenopteron foordi (Crossopterygii), Ichthyostega and Acanthostega (Labyrinthodontia) between Osteichthyes and Amphibia, Seymouria baylorensis (Amphibiosaria) between Amphibia and Reptilia, Archaeopteryx lithographica (Archaeornithes) between Reptilia and Aves, and the mammal-like reptiles Pelycosauria, Therapsida and Cynodontia between Reptilia and Aves, and the description of their phylogenetical heterochronies in terms of peramorphosis and paedomorphosis shows the progressive role of the motorial, especially the locomotorial organ systems and their functions in comparison with the retarded evolution of the axial system, especially the skull and central nervous system. The evolution of the Hominidae shows the same rule. The evaluation of these transitional forms in their fossil context reveals them as inhabitants of biotopes situated in the border areas of coastal and shore landscapes of marine, brackish or fresh water. These biotopes have obviously favoured the innovations on the high taxonimic level of macro-evolutionary characteristics. Authors Trinkaus E. Institution Department of Anthropology, University of New Mexico, Albuquerque 87131. Title Cladistics and the hominid fossil record [see comments]. [Review] Source American Journal of Physical Anthropology. 83(1):1-11, 1990 Sep. Abstract Cladistic methodology has become common in phylogenetic analyses of the hominid fossil record. Even though it has correctly placed emphasis on morphology for the primary determination of affinities between groups and on explicit statements regarding traits and methods employed in making phylogenetic assessments, cladistics nonetheless has limitations when applied to the hominid fossil record. These include 1) the uncritical assumption of parsimony, 2) uncertainties in the identification of homoplasies, 3) difficulties in the appropriate delimitation of samples for analysis, 4) failure to account for normal patterns of variation, 5) methodological problems with the appropriate identification of morphological traits involving issues of biological relevance, intercorrelation, primary versus secondary characters, and the use of continuous variables, 6) issues of polarity identification, and 7) problems in hypothesis testing. While cladistics has focused attention on alternative phylogenetic reconstructions in hominid paleontology and on explicit statements regarding their morphological and methodological underpinnings, its biological limitations are too abundant for it to be more than a heuristic device for the preliminary ordering of complex human paleontological and neonatological data. [References: 69] Authors Diamond MK. Institution Department of Organismal Biology and Anatomy, University of Chicago, Illinois 60637. Title Homologies of the stapedial artery in humans, with a reconstruction of the primitive stapedial artery configuration of Euprimates. Source American Journal of Physical Anthropology. 84(4):433-62, 1991 Apr. Local Messages Data drawn from the perspectives of paleontology, comparative anatomy, embryology, teratology, and normal adult variation were analyzed with nine homology criteria in order to determine the homologues of the stapedial artery in adult humans. It was determined that 1) the stem of the stapedial artery does not persist within the cranial cavity; 2) the stem of the ramus inferior is retained in its entirety and forms the upper portion of the stem of the middle meningeal artery; 3) the proximal part of the ramus infraorbitalis is normally absent and is replaced by a collateral shunt arising from the ramus mandibularis; 4) the ramus mandibularis is retained and forms the lower portion of the middle meningeal stem and the inferior alveolar artery; 5) the most proximal portion of the maxillary artery is formed by an anastomotic shunt connecting the external carotid artery to the ramus mandibularis; 6) the anterior division of the ramus superior is normally present and well developed; 7) the posterior division of the ramus superior is present in many individuals; and 8) the junction of the two divisions of the ramus superior with the ramus inferior usually migrates to the floor of the middle cranial fossa. The range of human arterial patterns, and those of all other euprimates, can be derived from a hypothetical primitive pattern that is very similar to that of primitive rodents. In this pattern, the stapedial artery stem enters the middle cranial fossa and trifurcates into the anterior and posterior divisions of the ramus superior and the ramus inferior. In their evolution, strepsirhines initially lose the ramus inferior and haplorhines initially reduce the stapedial artery stem. Authors Fox RC. Youzwyshyn GP. Krause DW. Institution Laboratory for Vertebrate Paleontology, Department of Geology, University of Alberta, Edmonton, Canada. Title Post-Jurassic mammal-like reptile from the Palaeocene. Abstract Mammal-like reptiles of the order Therapsida document the emergence of mammals from more primitive synapsids and are of unique zoological and palaeontological interest on that account. Therapsids, first appearing in the Early Permian, were thought to become extinct in the Middle Jurassic, soon after the Late Triassic origin of mammals. Here, however, we report the discovery of a therapsid from the late Palaeocene, 100 million years younger than the youngest previous occurrence of the order. This discovery nearly doubles the stratigraphic range of therapsids and furnishes their first record from the Cenozoic. The documenting fossils, an incomplete dentary containing three teeth, and four isolated teeth from other, conspecific individuals (Fig. 1), are from the Paskapoo Formation, at Cochrane, Alberta, Canada, from beds yielding a diverse mammalian fauna of early Tiffanian age. These specimens are catalogued in the collections of the University of Alberta Laboratory for Vertebrate Paleontology (UALVP) and provide the basis for a new taxon, as named and described below: (see text) Authors Ciochon RL. Piperno DR. Thompson RG. Institution Department of Anthropology, University of Iowa, Iowa City 52242. Title Opal phytoliths found on the teeth of the extinct ape Gigantopithecus blacki: implications for paleodietary studies. Source Proceedings of the National Academy of Sciences of the United States of America. 87(20):8120-4, 1990 Oct. Abstract Identification of opal phytoliths bonded to the enamel surface of the teeth of Gigantopithecus blacki indicates that this extinct ape had a varied diet of grasses and fruits. By using the scanning electron microscope at magnifications of 2000-6000x specific opal phytoliths were observed and photographed on the fossilized teeth of an extinct species. Since opal phytoliths represent the inorganic remains of once-living plant cells, their documentation on the teeth of Gigantopithecus introduces a promising technique for the determination of diet in extinct mammalian species which should find numerous applications in the field of paleoanthropology as well as vertebrate paleontology. Authors Nee S. Mooers AO. Harvey PH. Institution Department of Zoology, University of Oxford, United Kingdom. Title Tempo and mode of evolution revealed from molecular phylogenies. Source Proceedings of the National Academy of Sciences of the United States of America. 89(17):8322-6, 1992 Sep 1. Abstract The analysis of the tempo and mode of evolution has a strong tradition in paleontology. Recent advances in molecular phylogenetic reconstruction make it possible to complement this work by using data from extant species. Authors Nee S. Mooers AO. Harvey PH. Institution Department of Zoology, University of Oxford, United Kingdom. Title Tempo and mode of evolution revealed from molecular phylogenies. Source Proceedings of the National Academy of Sciences of the United States of America. 89(17):8322-6, 1992 Sep 1. Abstract The analysis of the tempo and mode of evolution has a strong tradition in paleontology. Recent advances in molecular phylogenetic reconstruction make it possible to complement this work by using data from extant species. Authors Gould SJ. Institution Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138. Title Tempo and mode in the macroevolutionary reconstruction of Darwinism. [Review] Source Proceedings of the National Academy of Sciences of the United States of America. 91(15):6764-71, 1994 Jul 19. Abstract Among the several central meanings of Darwinism, his version of Lyellian uniformitarianism--the extrapolationist commitment to viewing causes of small-scale, observable change in modern populations as the complete source, by smooth extension through geological time, of all magnitudes and sequences in evolution--has most contributed to the causal hegemony of microevolution and the assumption that paleontology can document the contingent history of life but cannot act as a domain of novel evolutionary theory. G. G. Simpson tried to combat this view of paleontology as theoretically inert in his classic work, Tempo and Mode in Evolution (1944), with a brilliant argument that the two subjects of his title fall into a unique paleontological domain and that modes (processes and causes) can be inferred from the quantitative study of tempos (pattern). Nonetheless, Simpson did not cash out his insight to paleontology's theoretical benefit because he followed the strict doctrine of the Modern Synthesis. He studied his domain of potential theory and concluded that no actual theory could be found--and that a full account of causes could therefore be located in the microevolutionary realm after all. I argue that Simpson was unduly pessimistic and that modernism's belief in reductionistic unification (the conventional view of Western intellectuals from the 1920s to the 1950s) needs to be supplanted by a postmodernist commitment to pluralism and multiple levels of causation. Macro- and microevolution should not be viewed as opposed, but as truly complementary. I describe the two major domains where a helpful macroevolutionary theory may be sought--unsmooth causal boundaries between levels (as illustrated by punctuated equilibrium and mass extinction) and hierarchical expansion of the theory of natural selection to levels both below (gene and cell-line) and above organisms (demes, species, and clades). Problems remain in operationally defining selection at non-organismic levels (emergent traits vs. emergent fitness approaches, for example) and in specifying the nature and basis of levels, but this subject should be the central focus in formulating a more ample and satisfactory general theory of evolution on extended Darwinian principles. [References: 43] Authors Savic IR. Nevo E. Institution Institute of Zoology, Faculty of Science, University of Belgrade, Yugoslavia. Title The Spalacidae: evolutionary history, speciation and population biology. [Review] Source Progress in Clinical & Biological Research. 335:129-53, 1990. Abstract The evolutionary history of Spalacidae is reviewed taxonomically, paleontologically and neontologically. We focused selectively on taxonomy, biogeography, paleontology and evolutionary origins, chromosomal evolution, population biology and the species concept in Spalacidae. We concluded that the taxonomy of Spalacidae needs a modern revision based on chromosome and molecular-genetic data, beside that of morphology, physiology and behavior. The subterranean Spalacidae originated probably from a muroid-cricetoid stock in Asia Minor or vicinity, in Upper Oligocene times and adaptively radiated underground in the Balkans, steppic Russia and Middle East, extending into North Africa. The major important evolutionary feature in peripatric or allopatric speciation and adaptive radiation was karyotypic evolution, primarily through Robertsonian changes. More than 30 karyotypes (2n = 38-62; NF = 72-124) earlier represented by 8 classical species, occur primarily allopatrically or parapatrically, with only marginal sympatry, across the Eastern Mediterranean range of the family. Most karyotypes represent biospecies adapted at multiple organizational levels to their different ecologies. A short overview is presented on population biology and life history parameters of the Spalacidae which result in K-selected, "equilibrium species". Speciation in action and adaptive radiation embracing molecular and organismal adptations to the subterranean unique ecotope and to four different climatic regimes, have been multidisciplinarily studied in the Israeli Spalax ehrenbergi superspecies. [References: 75] In truth, I have read some of the above material. When Dr. Gould tells me that there is a serious flaw in evolutionary theory, I will believe it. For every one of the haphazard ICR tractw you post, I have THOUSANDS of articles that show that evolution occured.

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