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Ideas on the timing of metazoan diversification

Published online by Cambridge University Press:  08 April 2016

Steven M. Stanley*
Affiliation:
Department of Earth and Planetary Sciences, The Johns Hopkins University; Baltimore, Maryland 21218

Abstract

Fossil data suggest that the great majority of metazoan classes that existed in the Early Cambrian arose after about 700 my ago. The rectangular model of evolution, which views most evolutionary change as being concentrated in speciation events, can easily accommodate the implied rate of divergence.

If, as some authors believe, the eukaryotic cell arose long before the start of the Cambrian, an explanation is required for the delay of large-scale metazoan divergence. The advent of sexuality may have triggered diversification, not by accelerating phyletic evolution, as traditionally believed, but by making possible speciation and, hence, adaptive radiation. Another important delaying factor may have been the near-saturation of Precambrian algal systems in the absence of cropping by herbivores. Uncropped Precambrian systems should have been self-limiting in terms of diversification. When advanced heterotrophy finally arose, self-propagating feedback systems of diversification should have been set in motion. Even if the eukaryotic cell arose later than commonly envisioned and triggered the radiation of the Metazoa about 700 my ago, the earlier absence of sexuality and cropping may have delayed the transition from the prokaryotic condition to the eukaryotic condition.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Arnold, D. E. 1971. Ingestion, assimilation, survival, and reproduction by Daphnia pulex fed seven species of blue-green algae. Limnol. Oceanogr. 16:906920.CrossRefGoogle Scholar
Bailey-Watts, A. E. 1968. Freshwater primary production by a blue-green alga of bacterial size. Nature. 220:13441345.Google Scholar
Banks, N. L. 1970. Trace fossils from the late Precambrian and Lower Cambrian of Finmark, Norway. pp. 1934. In: Crimes, T. P. and Harper, J. C., eds. Trace Fossils. Geol. J. Spec. Issue 3.Google Scholar
Banks, N. L. 1973. Trace fossils in the Halkkavarre section of the Dividal Group (? late Precambrian-Lower Cambrian), Finmark. Norges Geol. Unders. 288:16.Google Scholar
Berkner, L. V. and Marshall, L. C. 1964. The history of oxygenic concentration in the earth's atmosphere. Discuss. Faraday Soc. 37:122141.Google Scholar
Boucot, A. 1975. Evolution and Extinction Rate Controls. 427 p. Elsevier; Amsterdam.Google Scholar
Cairns, J. Jr., Dickson, K. L., and Yongue, W. H. 1971. The consequences of nonselective periodic removal of portions of freshwater protozoan communities. Trans. Am. Microsc. Soc. 90:7180.CrossRefGoogle Scholar
Cloud, P. E. 1972. A working model of the primitive earth. Am. J. Sci. 272:537548.Google Scholar
Cloud, P. E., Licari, G. R., Wright, L. A., and Troxel, B. W. 1969. Proterozoic eukaryotes from eastern California. Proc. Nat. Acad. Sci. 62:623630.Google Scholar
Cowie, J. W. and Spencer, A. M. 1970. Trace fossils from the late Precambrian/Lower Cambrian of East Greenland. pp. 91100. In: Crimes, T. P. and Harper, J. C., eds. Trace Fossils. Geol. J. Spec. Issue 3.Google Scholar
Dayton, P. K. 1971. Competition, disturbance, and community organization: the provision and subsequent utilization of space in a rocky intertidal community. Ecol. Monogr. 41:351389.CrossRefGoogle Scholar
Dayton, P. K. and Hessler, R. R. 1972. Role of biological disturbance in maintaining diversity in the deep sea. Deep Sea Res. 19:199208.Google Scholar
Durham, J. W. 1969. The fossil record and the origin of the Deuterostomata. Proc. North Am. Paleontol. Convention. pp. 11041132.Google Scholar
Eldredge, N. and Gould, S. J. 1972. Punctuated equilibria: an alternative to phyletic gradualism. pp. 82115. In: Models in Paleobiology. Schopf, T. J. M., ed. W. H. Freeman and Co.; San Francisco, Calif.Google Scholar
Fenchel, T. 1968. The ecology of marine micro-benthos. II. The food of marine benthic ciliates. Ophelia. 5:73121.Google Scholar
Fischer, A. G. 1965. Fossils, early life, and atmospheric history. Proc. Nat. Acad. Sci. 53:12051215.CrossRefGoogle Scholar
Gächter, R. 1968. Phosphorhaushalt und planktische Primäproduktion im Vierwaldstättersee (Horwer Bucht). Schweiz. Zeitschr. Hydrol. 30:166.Google Scholar
Ganapati, S. V. 1941. Ecology of a temple tank containing a permanent bloom of Microcystis aeruginosa. J. Bombay Nat. Hist. Soc. 42:6577.Google Scholar
Garrels, R. M., Perry, E. A. Jr., and Mackenzie, F. T. 1973. Genesis of Precambrian iron-formations and the development of atmospheric oxygen. Econ. Geol. 68:11731179.Google Scholar
Garrett, P. 1970. Phanerozoic stromatolites: noncompetitive ecologic restriction by grazing and burrowing animals. Science. 167:171173.CrossRefGoogle Scholar
Germs, G. J. B. 1972. Trace fossils from the Nama Group, South-west Africa. J. Paleontol. 46:864870.Google Scholar
Glaessner, M. F. 1962. Pre-Cambrian fossils. Biol. Rev. 37:467494.Google Scholar
Glaessner, M. F. 1969. Trace fossils from the Precambrian and basal Cambrian. Lethaia. 2:369393.Google Scholar
Harper, J. L. 1969. The role of predation in vegetational diversity. Brookhaven Symp. 22:4862.Google Scholar
Heller, J. 1955. Catch-22. 436 pp. Simon and Schuster; New York.Google Scholar
Hutchinson, G. E. 1948. Circular causal systems in ecology. Ann N. Y. Acad. Sci. 50:221246.Google Scholar
Hutchinson, G. E. 1961. The paradox of the plankton. Am. Nat. 95:137146.CrossRefGoogle Scholar
Jackson, J. B. C. 1974. Biogeographic consequences of eurytopy and stenotopy among marine bivalves and their evolutionary significance. Am. Nat. 108:541560.Google Scholar
Janzen, D. H. 1970. Herbivores and the number of tree species in tropical forests. Am. Nat. 104:501528.CrossRefGoogle Scholar
Knoll, A. H. and Barghoorn, E. S. 1975. Precambrian eukaryotic organisms: a reassessment of the evidence. Science. 190:5254.Google Scholar
Kudo, R. 1966. Protozoology. 1174 pp. C. C. Thomas; Springfield, Ill.Google Scholar
Leedale, G. F. 1967. Euglenoid flagellates. 242 pp. Prentice-Hall; Englewood Cliffs, N. J.Google Scholar
Lefèvre, M. 1932. Recherches sur la biologie et al systématique de quelques algues obtenues en culture. Rev. Algol. 6:313338.Google Scholar
Lin, C. K. 1972. Phytoplankton succession in a eutrophic lake with special reference to blue-green algal blooms. Hydrobiologia. 39:321334.Google Scholar
Lund, J. W. G. 1964. Primary production and periodicity of planktonic algae. Verh. Int. Ver. Limnol. 15:3756.Google Scholar
Lund, J. W. G. 1965. The ecology of the freshwater phytoplankton. Biol. Rev. 40:231293.CrossRefGoogle Scholar
Maguire, B. Jr. 1971a. Community structure of protozoans and algae with particular emphasis on recently colonized bodies of water. pp. 121149. In: Cairns, J., ed. The Structure and Function of Fresh-water Microbial Communities. Virginia Polytech. Inst, and State Univ. Res. Div. Monogr. 3.Google Scholar
Maguire, B. Jr. 1971b. Phytotelmata: biota and community structure determination in plant-held waters. Annu. Rev. Ecol. Syst. 2:439464.Google Scholar
Monty, C. 1972. Recent algal stromatolite deposits, Andros Island, Bahamas. Preliminary report. Geol. Rundsch. 61:742783.Google Scholar
Novak, M. 1961. Změmy ve složeni planktoní bioceńozy v abodbí masoveho výskytu sinice Aphanizomenon flos-aquae. S. bornik Čsekoslovenskí Akademie Zemedelsky̆ch Věd, Ruĭnik 6:303310.Google Scholar
Novatskiy, V. S. Zaika-, Velikanov, V. A., and Koval, A. P. 1968. First member of the Ediacara Fauna in the Wendian of the Russian Platform (upper Precambrian). Paleontol. J. 2:132134.Google Scholar
Nursall, J. R. 1959. Oxygen as a prerequisite to the origin of the Metazoa. Nature. 183:11701172.Google Scholar
Paine, R. T. 1966. Food web complexity and species diversity. Am. Nat. 100:6575.Google Scholar
Paine, R. T. and Vadas, R. L. 1969. The effects of grazing by sea urchins, Strongylocentrotus spp., on benthic algal populations. Limnol. Oceanogr. 14:710719.Google Scholar
Phillips, O. M. 1973. The equilibrium and stability of simple marine biological systems. I. Primary nutrient consumers. Am. Nat. 107:7393.Google Scholar
Phillips, O. M. 1974. The equilibrium and stability of simple marine biological systems. II. Herbivores. Arch. Hydrobiol. 73:310333.CrossRefGoogle Scholar
Porter, K. G. 1973. The selective effects of grazing by zooplankton on the phytoplankton of Fuller Pond, Kent, Connecticut [Ph.D. Thesis]. 185 pp. Yale Univ.; New Haven, Conn.Google Scholar
Raff, R. A. and Raff, E. C. 1970. Respiratory mechanisms and the metazoan fossil record. Nature. 228:10031005.Google Scholar
Rhoads, D. C. and Morse, J. W. 1971. Evolutionary and ecologic significance of oxygen-deficient marine basins. Lethaia. 4:413428.Google Scholar
Schopf, J. W. 1968. Microflora of the Bitter Springs Formation, Late Precambrian, central Australia. J. Paleontol. 42:651688.Google Scholar
Schopf, J. W. and Barghoorn, E. S. 1969. Microorganisms from the late Precambrian of South Australia. J. Paleontol. 43:111118.Google Scholar
Schopf, J. W. and Blacic, J. M. 1971. New microorganisms from the Bitter Springs Formation (late Precambrian) of the north-central Amadeus Basin, Australia. J. Paleontol. 45:925960.Google Scholar
Schopf, J. W., Ford, T. W., and Breed, W. J. 1973. Microorganisms from the late Precambrian of the Grand Canyon, Arizona. Science. 179:13191323.Google Scholar
Schopf, J. W., Haugh, B. N., Molnar, R. E., and Satterthwait, D. F. 1973. On the development of metaphytes and metazoans. J. Paleontol. 47:19.Google Scholar
Schopf, J. W. and Oehler, B. Z. 1976. How old are the eukaryotes? Science. In press.Google Scholar
Singh, R. N. 1955. Limnological relations of Indian inland waters with special reference to waterblooms. Verh. Int. Verein. Theor. Angew. Limnol. 12:831836.Google Scholar
Stanley, S. M. 1973. An ecological theory for the sudden origin of multicellular life in the late Precambrian. Proc. Nat. Acad. Sci. 70:14861489.CrossRefGoogle ScholarPubMed
Stanley, S. M. 1975a. A theory of evolution above the species level. Proc. Nat. Acad. Sci. 72:646650.Google Scholar
Stanley, S. M. 1975b. Clades versus clones in evolution: why we have sex. Science 190:382383.Google Scholar
Stanley, S. M. 1975c. Fossil data and the Precambrian-Cambrian evolutionary transition. Am. J. Sci. 276:5676.Google Scholar
Stanley, S. M. 1976. Stability of species in geologic time. Science. 192:267269.CrossRefGoogle ScholarPubMed
Steele, J. H. 1974. The structure of marine ecosystems. 128 pp. Harvard Univ. Press; Cambridge, Mass.Google Scholar
Sutherland, J. P. 1974. Multiple stable points in natural communities. Am. Nat. 108:859873.Google Scholar
Tappan, H. and Loeblich, A. R. 1970. Geobiologic implications of fossil phytoplankton evolution and time-space distribution. Geol. Soc. Am. Spec. Pap. 127:247340.Google Scholar
Tassigny, M. and Lefèvre, M. 1971. Auto., heteroantagonisme et autres consequences des excretions d'algues d'eau douce ou thermale. Mitt. Int. Verein. Theor. Angew. Limnol. 19:2638.Google Scholar
Towe, K. M. 1970. Oxygen-collagen priority and the early metazoan fossil record. Proc. Nat. Acad. Sci. 65:781788.Google Scholar
Webby, B. D. 1970. Late Precambrian trace fossils from New South Wales. Lethaia. 3:79109.Google Scholar
Whitton, B. A. 1969. Seasonal changes in the phytoplankton of St. James' Park Lake, London. London Nat. 48:1439.Google Scholar
Whitton, B. A. 1973a. Freshwater plankton. pp. 353367. In: Carr, N. C. and Whitton, B. A., eds. The Biology of Blue-green Algae. Bot. Monogr.Google Scholar
Whitton, B. A. 1973b. Interactions with other organisms. pp. 415433. In: Carr, N. G. and Whitton, B. A., eds. The Biology of Blue-green Algae. Bot. Monogr.Google Scholar
Young, F. G. 1972. Early Cambrian and older trace fossils from the southern Cordillera of Canada. Can. J. Earth Sci. 9:117.Google Scholar