Patterns and Processes in the History of Life pp 209-222 | Cite as
Fossil Record of the Origin of Baupläne and Its Implications
Abstract
Animal Baupläne and Unterbaupläne appear abruptly in the fossil record, mostly developing early in Phanerozoic time; metazoan radiations near the Precambrian/Cambrian boundary may have produced scores of phylum-level taxa, and during Cambrian and Ordovician time, hundreds of class-level taxa. Ancestors and intermediates are unknown or are conjectural as fossils. About one in ten invertebrate species is a known fossil, and sampling of the Cambrian and Ordovician faunas appears at least average for the Phanerozoic, so that many species representing ancestral and intermediate lineages should have been discovered if they could be fossilized as easily as the average species which is found. Transformations between Baupläne most likely occurred in small localized populations which evolved rapidly, perhaps the restructuring of a partitioned genome via regulatory changes, commonly creating heterochronies, can account for the large-scale but rapid morphological changes required. Virtual restriction of Bauplan origin to the early Phanerozoic may be owing to the open adaptive space and to simpler metazoan genomes at that time.
Keywords
Fossil Record Lower Cambrian Trace Fossil Adaptive Peak Adaptive ZonePreview
Unable to display preview. Download preview PDF.
References
- 1.Bannister JV, Parker MW (1985) The presence of a copper/zinc superoxide dismutase in the bacterium Photobactorium leiognathi: A likely case of gene transfer from eukaryotes to prokaryotes. Proc Natl Acad Sci USA 82: 149–152PubMedCrossRefGoogle Scholar
- 2.Benveniste RE (1985) The contribution of retroviruses to the study of mammalian evolution. In: Molecular evolutionary genetics, ed Maclntyre RJ. New York: PlenumGoogle Scholar
- 3.Cloud PE (1949) Some problems and patterns of evolution exemplified by fossil invertebrates. Evolution 2: 322–350CrossRefGoogle Scholar
- 4.Conway Morris S (1979) The Burgess Shale (Middle Cambrian) fauna. Ann Rev Ecol Syst 10: 327–349CrossRefGoogle Scholar
- 5.Crimes TP (1974) Colonisation of the early ocean floor. Nature 248: 328–330CrossRefGoogle Scholar
- 6.Eldredge N, Gould SJ (1972) Punctuated equilibria: an alternative to phyletic gradualism. In: Models in Paleobiology, ed Schopf TJM, pp 82–115. San Francisco: Freeman, CooperGoogle Scholar
- 7.Erwin DH, Valentine JW (1984) “Hopeful monsters,” transposons, and Metazoan radiation. Proc Natl Acad Sci USA 81: 5482–5483PubMedCrossRefGoogle Scholar
- 8.Glaessner MF (1984) The dawn of animal life, a biohistorical study. Cambridge: Cambridge University PressGoogle Scholar
- 9.House MR (ed) (1979) The origin of major invertebrate groups. London: Academic PressGoogle Scholar
- 10.Jablonski D, Sepkoski J J Jr, Bottjer DJ, Sheehan PM (1983) Onshore-offshore patterns in the evolution of Phanerozoic shelf communities. Science 222: 1123–1125PubMedCrossRefGoogle Scholar
- 11.Lande R (1980) Genetic variation and phenotypic evolution during allopatric speciation. Am Nat 116: 463–479CrossRefGoogle Scholar
- 12.Lowenstam HA, Margulis L (1980) Evolutionary prerequisites for early Phanerozoic calcareous skeletons. Biosystems 12: 27–41PubMedCrossRefGoogle Scholar
- 13.Matthews SC, Missarzhevsky VV (1975) Small shelly fossils of Late Precambrian and Early Cambrian age: A review of recent work. J Geol Soc Lond 131: 289–304CrossRefGoogle Scholar
- 14.Raup DM (1976) Species diversity in the Phanerozoic: A tabulation. Paleobiology 2: 279–288Google Scholar
- 15.Rozanov AY et al. (1969) Tommotski Yarus i problema nizheni Grantitsy Keembriya [Tommotion Stage and the Lower Cambrian boundary problem]. Trudy Geol Inst Akad Nauk SSSR 206: 1–380 (in Russian)Google Scholar
- 16.Runnegar B (1982) The Cambrian explosion: animals or fossils? J Geol Soc Austral 29: 395–411CrossRefGoogle Scholar
- 17.Sadler DM (1981) Sediment accumulation rates and the completeness of stratigraphie sections. J Geol 89: 569–584CrossRefGoogle Scholar
- 18.Seilacher A (1964) Biogenic sedimentary structures. In: Approaches to Paleocology, eds Imbrie J, Newell ND, pp 296–316. New York: WileyGoogle Scholar
- 19.Stanley SM (1979) Macroevolution, pattern and process. San Francisco: Freeman and CoGoogle Scholar
- 20.Valentine JW (1973) Evolutionary paleoecology of the marine biosphere. Englewood Cliffs, NJ: Prentice-HallGoogle Scholar
- 21.Valentine JW (1980) Determinants of diversity in higher taxonomic categories. Paleobiology 6: 444–450Google Scholar
- 22.Valentine JW (1981) The lophophorate condition. In: Lophophorates, eds Dutro JT Jr, Boardman RS, pp 190–204. University of Tennessee Department of Geological Sciences Studies in Geology 5Google Scholar
- 23.Valentine JW, Erwin DH (1983) Patterns of diversification of higher taxa: A test of macroevolutionary paradigms. In: Modalités, rhythmes et mécanismes de l’évolution biologique: Gradualism phyletique on équilibrés ponctues?, ed Chaline J. Coll Int CNRS 330: 219–223Google Scholar
- 24.Valentine JW, Foin TC, Peart D (1978) A provincial model of Phanerozoic marine diversity. Paleobiology 4: 55–66Google Scholar
- 25.Wright S (1982) Character change, speciation, and the higher taxa. Evolution 36: 427–443CrossRefGoogle Scholar