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The environmental structure of trilobite morphological disparity

Published online by Cambridge University Press:  08 April 2016

Melanie J. Hopkins*
Affiliation:
Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung an der Humboldt-Universität, Invalidenstraße 43, 10115 Berlin, Germany, and GeoZentrum Nordbayern, Friedrich-Alexander-Universität Erlangen-Nürnberg, Loewenichstraße 28, 91054 Erlangen, Germany

Abstract

Despite the mounting evidence that taxonomic diversity dynamics are patterned environmentally and that taxonomic diversity and morphological disparity are decoupled both temporally and spatially in many clades, very little work has been done to assess whether disparity is also influenced by environment. Here I investigate whether trilobite disparity shows environmental patterning through time. I used the method developed by Simpson and Harnik (2009) for estimating latitudinal, substrate, and bathymetric affinities from fossil occurrence data, downloaded from the Paleobiology Database. This method has the advantages that the biological null hypothesis is explicitly separated from the expectation due to sampling, and that the posterior probability can be used to infer degree of preference for one habitat compared to another. To measure morphology, I used a data set of outlines of the trilobite cranidium from Foote (1993). Many of the species in this data set are not represented in the Paleobiology Database in sufficient numbers to assess species-level affinity for these taxa, but species-level affinity could be estimated with high fidelity by using genus-level affinities. Results show that cranidial morphological diversity was structured by environmental preferences of the taxa but the structure was complex and changed through time. In particular, there was little differentiation in morphospace around latitudinal, substrate, or bathymetric affinity during the Cambrian. In contrast, both diversification and expansion into previously unoccupied areas of morphospace during the Ordovician were dominated by tropical, deeper-water taxa.

Type
Articles
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Adrain, J. M., Edgecombe, G. D., Fortey, R. A., Hammer, O., Laurie, J. R., McCormick, T., Owen, A. W., Waisfeld, B. G., Webby, B. D., Westrop, S. R., and Zhou, Z. 2004. Trilobites. Pp. 231254inWebby, B. D., Paris, F., Droser, M. L., and Percival, I. G., eds. The great Ordovician biodiversification event. Columbia University Press, New York.CrossRefGoogle Scholar
Brett, C. E., and Liddell, W. D. 1978. Preservation and paleoecology of a Middle Ordovician hardground community. Paleobiology 4:329348.Google Scholar
Bromley, R. G., and Heinberg, C. 2006. Attachment strategies of organisms on hard substrates: a paleontological view. Palaeogeography, Palaeoclimatology, Palaeoecology 232:429453.Google Scholar
DeGusta, D., and Vrba, E. S. 2003. A method for inferring paleohabitats from the functional morphology of bovid astragali. Journal of Archeological Science 30:10091022.Google Scholar
Deline, B., and Ausich, W. I. 2011. Testing the plateau: a reexamination of disparity and morphological constraints in early Paleozoic crinoids. Paleobiology 37:214236.Google Scholar
Finnegan, S., and Droser, M. L. 2008. Body size, energetics, and the Ordovician restructuring of marine ecosystems. Paleobiology 34:342359.Google Scholar
Foote, M. 1989. Perimeter-based Fourier analysis: a new morphometric method applied to the trilobite cranidium. Journal of Paleontology 63:880885.Google Scholar
Foote, M. 1991. Morphologic patterns of diversification: examples from trilobites. Palaeontology 34:461485.Google Scholar
Foote, M. 1993. Discordance and concordance between morphological and taxonomic diversity. Paleobiology 19:185204.Google Scholar
Foote, M. 1997. The evolution of morphological diversity. Annual Review of Ecology, Evolution, and Systematics 28:129152.Google Scholar
Foote, M. 1999. Morphological diversity in the evolutionary radiation of Paleozoic and post-Paleozoic crinoids. Paleobiology 25:1115.CrossRefGoogle Scholar
Foote, M. 2006. Substrate affinity and diversity dynamics of Paleozoic marine animals. Paleobiology 32:345366.Google Scholar
Fortey, R. A., and Owens, R. M. 1990. Trilobites. Pp121142inMcNamara, J. M., ed. Evolutionary trends. Belhaven, London.Google Scholar
Fortey, R. A., and Owens, R. M. 1997. Evolutionary history. Pp. 249287in Kaesler 1997.Google Scholar
Fortey, R. A., and Owens, R. M. 1999. Feeding habits in trilobites. Palaeontology 42:429465.Google Scholar
Gerber, S., and Hopkins, M. J. 2011. Mosaic heterochrony and evolutionary modularity: the trilobite genus Zacanthopsis as a case study. Evolution 65:32413252.Google Scholar
Hillebrand, J. 2004. On the generality of the latitudinal diversity gradient. American Naturalist 163:192211.Google Scholar
Holland, S. M., and Zaffos, A. 2011. Niche conservatism along an onshore-offshore gradient. Paleobiology 37:270286.Google Scholar
Hopkins, M. J. 2011. The influence of morphological variation and geographic range size on species longevity in late Cambrian trilobites. Evolution 65:32523273.Google Scholar
Hopkins, M. J., and Webster, M. 2008. Morphological and ontogenetic change in the “Early” Cambrian trilobite Zacanthopsis during an interval of environmental change. Pp. 185187inRabano, I., Gozolo, R., and Garcia-Bellido, D. C., eds. Advances in trilobite research. Instituto Geológico y Minero de España, Cuadernos del Museo Geominero 9, Madrid.Google Scholar
Hopkins, M. J., and Webster, M. 2009. Ontogeny and geographic variation of a new species of the corynexochine trilobite Zacanthopsis (Dyeran, Cambrian). Journal of Paleontology 83:524547.Google Scholar
Hughes, N. C. 2005. Trilobite construction: building a bridge across the micro- and macroevolutionary divide. Pp. 139158inBriggs, D. E. G., ed. Evolving form and function: fossils and development. Proceedings of a symposium honoring Adolf Seilacher for his contributions to palentology, in celebration of his 80th birthday. Peabody Museum of Natural History, Yale University, New Haven.Google Scholar
Hughes, N. C. 2007. The evolution of trilobite body patterning. Annual Review of Ecology, Evolution, and Systematics 35:401434.Google Scholar
Jablonski, D. 1993. The tropics as a source of evolutionary novelty through geological time. Nature 364:142144.Google Scholar
Jablonski, D. 2005. Evolutionary innovations in the fossil record: the intersection of ecology, development, and macroevolution. Journal of Experimental Zoology B 304:504519.CrossRefGoogle ScholarPubMed
Jablonski, D., and Bottjer, D. J. 1991. Environmental patterns in the origins of higher taxa: the post-Paleozoic fossil record. Science 252:18311833.Google Scholar
Jablonski, D., Lidgard, S., and Taylor, P. D. 1997. Comparative ecology of bryozoan radiations: origin of novelties in cyclostomes and cheilostomes. Palaios 12:505523.Google Scholar
Jablonski, D., Roy, K., and Valentine, J. W. 2006. Out of the tropics: evolutionary dynamics of the latitudinal diversity gradient. Science 314:102106.Google Scholar
Kaesler, R. L.ed. 1997. Treatise on invertebrate paleontology, Part O, Arthropoda 1, Trilobita, revised. Geological Society of America, Boulder, Colo., and University of Kansas Press, Lawrence.Google Scholar
Kiessling, W., and Aberhan, M. 2007. Environmental determinants of marine benthic biodiversity dynamics through Triassic–Jurassic time. Paleobiology 33:414434.Google Scholar
Kiessling, W., Flügel, E., and Golonka, J. 2003. Patterns of Phanerozoic carbonate platform sedimentation. Lethaia 36:195225.Google Scholar
Kiessling, W., Simpson, C., and Foote, M. 2010. Reefs as cradles of evolution and sources of biodiversity in the Phanerozoic. Science 327:196198.Google Scholar
Kim, K., Sheets, H. D., and Mitchell, C. E. 2009. Geographic and stratigraphic change in the morphology of Triarthrus beckii (Green) (Trilobita): a test of the Plus ça change model of evolution. Lethaia 42:108125.Google Scholar
Lane, P. D. 1972. New trilobites from the Silurian of north-east Greenland, with a note on trilobite faunas in pure limestones. Palaeontology 15:336364.Google Scholar
Lupia, R. 1999. Discordant morphological disparity and taxonomic diversity during the Cretaceous. Paleobiology 25:129.Google Scholar
McClain, C. R. 2005. Bathymetric patterns of morphological disparity in deep-sea gastropods from the western North Atlantic Basin. Evolution 59:14921499.Google Scholar
McNamara, K. J., and Rudkin, D. M. 1984. Techniques of trilobite exuviation. Lethaia 17:153173.CrossRefGoogle Scholar
Miall, A. D., and Blakey, R. C. 2008. The Phanerozoic tectonic and sedimentary evolution of North America. Pp. 129. InMiall, A. D., ed. Sedimentary basins of the United States and Canada. Elsevier, Amsterdam.Google Scholar
Miller, A. I., and Connolly, S. R. 2001. Substrate affinities of higher taxa and the Ordovician Radiation. Paleobiology 27:768778.Google Scholar
Miller, A. I., and Foote, M. 2009. Epicontinental seas versus open-ocean settings: the kinetics of mass extinction and origination. Science 326:11061109.Google Scholar
Miller, A. I., and Mao, S. 1998. Scales of diversification and the Ordovician radiation. Pp. 288310. InMcKinney, M. L., and Drake, J. A., eds. Biodiversity dynamics: turnover of populations. Columbia University Press, New York.Google Scholar
Neige, P. 2003. Spatial patterns of disparity and diversity of the Recent cuttlefishes (Cephalopoda) across the Old World. Journal of Biogeography 30:11251137.Google Scholar
Palmer, A. R., and Repina, L. N. 1997. Introduction to the suborder Olenellina. Pp405428inKaesler 1997.Google Scholar
Peters, S. E. 2008. Environmental determinants of extinction selectivity in the fossil record. Nature 454:626629.Google Scholar
Plummer, T. W., Bishop, L. C., and Hertel, F. 2008. Habitat preference of extant African bovids based on astragalus morphology: operationalizing ecomorphology for palaeoenvironmental reconstruction. Journal of Archeological Science 35:30163027.Google Scholar
Pohler, S. M. L., and James, N. P. 1989. Reconstruction of a Lower/Middle Ordovician carbonate shelf margin: Cow Head Group, western Newfoundland. Facies 21:189262.Google Scholar
Ricklefs, R. E., and Miles, D. B. 1994. Ecological and evolutionary inferences from morphology: an ecological perspective. Pp. 1341inWainwright, P. C. and Reilly, S. M., eds. Ecological morphology. University of Chicago Press, Chicago.Google Scholar
Ridley, M. 1996. Evolution, 2nd ed. Blackwell Scientific, Cambridge, Mass.Google Scholar
Rohlf, F. J., and Archie, J. W. 1984. A comparison of Fourier methods for the description of wing shape in mosquitoes (Diptera: Culicidae). Systematic Zoology 33:302317.Google Scholar
Ross, R. J. Jr. 1951. Stratigraphy of the Garden City Formation in northeastern Utah, and its trilobite faunas. Bulletin of the Peabody Museum of Natural History, Yale University 6:1161.Google Scholar
Roy, K., Balch, D. P., and Hellberg, M. E. 2001. Spatial patterns of morphological diversity across the Indo-Pacific: analyses using strombid gastropods. Proceedings of the Royal Society of London B 268:25032508.Google Scholar
Sepkoski, J. J. Jr. 1991. A model of onshore-offshore change in faunal diversity. Paleobiology 17:5877.Google Scholar
Simpson, C., and Harnik, P. G. 2009. Assessing the role of abundance in marine bivalve extinction over the post-Paleozoic. Paleobiology 35:631647.Google Scholar
Sundberg, F. A. 1996. Morphological diversification of Ptychopariida (Trilobita) from the Marjumiid biomere (Middle and Upper Cambrian). Paleobiology 22:4965.Google Scholar
Swan, A. R. H., and Saunders, J. J. 1987. Function and shape in late Paleozoic (mid-Carboniferous) ammonoids. Paleobiology 37:409423.Google Scholar
Toledo, N., Bargo, M. S., Cassini, G. H., and Vizcaino, S. F. 2012. The forelimb of Early Miocene sloths (Mammalia, Xenarthra, Folivora): morphometrics and functional implications for substrate preferences. Journal of Mammalian Evolution 19:185198.Google Scholar
Vaughan, A. P. M. 2007. Climate and geology—a Phanerozoic perspective. Pp. 560inWilliams, M., Haywood, A. M., Gregory, F. J., and Schmidt, D. N., eds. Deep-time perspectives on climate change: marrying the signal from computer models and biological proxies. Micropalaeontological Society Special Publications. Geological Society, London.Google Scholar
Wagner, P. J. 1997. Patterns of morphological diversification among the Rostroconchia. Paleobiology 23:115150.Google Scholar
Webber, A. J., and Hunda, B. R. 2007. Quantitatively comparing morphological trends to environment in the fossil record (Cincinnatian Series, Upper Ordovician). Evolution 61:14551465.Google Scholar
Westrop, S. R., and Adrain, J. M. 1998. Trilobite alpha diversity and the reorganization of Ordovician benthic marine communities. Paleobiology 24:116.Google Scholar
Westrop, S. R., Tremblay, J. V., and Adrain, J. M. 1995. Declining importance of trilobites in Ordovician nearshore paleocommunities: dilution or displacement? Palaios 10:7579.CrossRefGoogle Scholar
Whittington, H. B. 1990. Articulation and exuviation in Cambrian trilobites. Philosophical Transactions of the Royal Society of London B 329:2746.Google Scholar
Whittington, H. B. 1997a. Mode of life, habits, and occurrence. Pp. 137169in Kaesler 1997.Google Scholar
Whittington, H. B. 1997b. Morphology of the exoskeleton. Pp. 185in Kaesler 1997.Google Scholar
Wills, M. A., Briggs, D. E. G., and Fortey, R. A. 1994. Disparity as an evolutionary index: a comparison of Cambrian and Recent arthropods. Paleobiology 20:93130.Google Scholar