Hostname: page-component-76fb5796d-dfsvx Total loading time: 0 Render date: 2024-04-26T14:01:12.043Z Has data issue: false hasContentIssue false
  • English
  • Français

Intracolony variation in colony morphology in reassembled fossil ramose stenolaemate bryozoans from the Upper Ordovician (Katian) of the Cincinnati Arch region, USA

Published online by Cambridge University Press:  26 July 2016

Marcus M. Key Jr. ,
Patrick N. Wyse Jackson  and
Stephen H. Felton
Marcus M. Key Jr.
Affiliation:
Department of Earth Sciences, Dickinson College, Carlisle, Pennsylvania 17013-2896, USA 〈key@dickinson.edu〉
Patrick N. Wyse Jackson
Affiliation:
Department of Geology, Trinity College, Dublin 2, Ireland 〈wysjcknp@tcd.ie〉
Stephen H. Felton
Affiliation:
DryDredgers.org, 5678 Biscayne Avenue, Cincinnati, Ohio 45248, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Clusters of associated colony fragments discovered weathering out of bedding planes in the Upper Ordovician of the Cincinnati, Ohio, region provide a rare opportunity to quantify intracolony variation in ramose stenolaemate bryozoans. Sixteen colonies were reassembled as completely as possible from 198 fragments, and the following colony-level characters were measured: colony dimensions, branch link length and diameter, and branch order. Results indicate that branch link length and diameter systematically decrease as colonies grow via branch bifurcation. Branching ratio (i.e., the number of distal first-order branches divided by the number of immediately proximal second-order branches) appears to be more genetically than environmentally controlled and to be consistent among orders of stenolaemates and perhaps across the phylum. Colonies with endozones mined out by endoskeletozoans result in broken branches as opposed to pristine growing tips. This varies stratigraphically, perhaps in response to the distribution of the boring animals. The rarity of borers and the systematic proximal increase in branch diameter in these colonies suggest the zooids in the proximal portions of the colonies were alive at the time of colony death. If the time and effort can be invested in reassembling colonies, these morphometric data can then be applied to taxonomic, phylogenetic, and paleoenvironmental studies.

Type
Articles
Information
Journal of Paleontology , Volume 90 , Issue 3 , May 2016 , pp. 400 - 412
Copyright
Copyright © 2016, The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Andres, M.S., and Reid, R.P., 2006, Growth morphologies of modern marine stromatolites: A case study from Highborne Cay, Bahamas: Sedimentary Geology, v. 185, p. 319–328.Google Scholar
Anstey, R.L., 1986, Bryozoan provinces and patterns of generic evolution and extinction in the Late Ordovician of North America: Lethaia, v. 19, p. 33–51.Google Scholar
Anstey, R.L., and Perry, T.G., 1973, Eden Shale bryozoans: A numerical study (Ordovician, Ohio Valley): Michigan State University Paleontological Series, v. 1, no. 1, p. 1–80.Google Scholar
Anstey, R.L., and Rabbio, S.F., 1989, Regional bryozoan biostratigraphy and taphonomy of the Edenian stratotype (Kope Formation, Cincinnati area): Graphic correlation and gradient analysis: Palaios, v. 4, p. 574–584.Google Scholar
Anstey, R.L., Rabbio, S.F., and Tuckey, M.E., 1987, Bryozoan bathymetric gradients within a Late Ordovician epeiric sea: Paleoceanography, v. 2, p. 165–176.CrossRefGoogle Scholar
Anstey, R.L., Pachut, J.F., and Tuckey, M.E., 2003, Patterns of bryozoan endemism through the Ordovician–Silurian transition: Paleobiology, v. 29, p. 305–328.Google Scholar
Bell, A.D., 1986, The simulation of branching patterns in modular organisms: Philosophical Transactions of the Royal Society of London, Series B, Biological Sciences, v. 313, p. 143–159.Google Scholar
Berning, B., 2007, The Mediterranean bryozoan Myriapora truncata (Pallas, 1766): A potential indicator of (palaeo-) environmental conditions: Lethaia, v. 40, p. 221–232.CrossRefGoogle Scholar
Boardman, R.S., 1960, Trepostomatous Bryozoa of the Hamilton Group of New York State: U.S. Geological Survey, Professional Paper 340, p. 1–87, pl. 1–22.Google Scholar
Boardman, R.S., and Utgaard, J.E., 1966, A revision of the Ordovician bryozoan genera Monticulipora, Peronopora, Heterotrypa, and Dekayia : Journal of Paleontology, v. 40, p. 1082–1108.Google Scholar
Brett, C.E., and Seilacher, A., 1991, Fossil Lagerstätten: A taphonomic consequence of event sedimentation, in Einsele, G., Ricken, W., and Seilacher, A., eds., Cycles and Events in Stratigraphy: Berlin, Springer Verlag, p. 284–297.Google Scholar
Brett, C.E., Kohrs, R.H., and Kirchner, B., 2008, Paleontological event beds from the Upper Ordovician Kope Formation of Ohio and northern Kentucky and the promise of high-resolution event stratigraphy, in McLaughlin, P.I., Brett, C.E., Holland, S.M., and Storrs, G.W., eds., Stratigraphic Renaissance in the Cincinnati Arch—Implications for Upper Ordovician Paleontology and Paleoecology: Cincinnati, Cincinnati Museum Center, p. 63–86.Google Scholar
Brown, G.D. Jr., and Daly, E.J., 1985, Trepostome Bryozoa from the Dillsboro Formation (Cincinnatian Series) of southeastern Indiana: Indiana Geological Survey, Special Report 33, p. 1–95.Google Scholar
Cheetham, A.H., 1971, Functional Morphology and Biofacies Distribution of Cheilostome Bryozoa in the Danian Stage (Paleocene) of Southern Scandinavia: Washington, D.C., Smithsonian Institution Press, 87 p.Google Scholar
Cheetham, A.H., 1986, Branching, biomechanics and bryozoan evolution: Proceedings of the Royal Society of London, Series B, Biological Sciences, v. 228, p. 151–171.Google Scholar
Cheetham, A.H., and Hayek, L.-A.C., 1983, Geometric consequences of branching growth in adeoniform Bryozoa: Paleobiology, v. 9, p. 240–260.Google Scholar
Cheetham, A.H., Hayek, L.-A.C., and Thomsen, E., 1980, Branching structure in arborescent animals: Models of relative growth: Journal of Theoretical Biology, v. 85, p. 335–369.Google Scholar
Cheetham, A.H., Hayek, L.-A.C., and Thomsen, E., 1981, Growth models in fossil arborescent cheilostome bryozoans: Paleobiology, v. 7, p. 68–86.Google Scholar
Chindapol, N., Kaandorp, J.A., Cronemberger, C., Mass, T., and Genin, A., 2013, Modelling growth and form of the scleractinian coral Pocillopora verrucosa and the influence of hydrodynamics: PLoS Computational Biology, v. 9, p. 1–15.Google Scholar
Coryell, H.N., 1921, Bryozoan faunas of the Stones River Group of central Tennessee: Proceedings of the Indiana Academy of Science, v. 1919, p. 261–340.Google Scholar
Cuffey, R.J., and Cheetham, A.H., 1982, Reconstruction of bryozoan colonies from measurements of branch fragments: Geological Society of America Abstracts with Programs, v. 14, no. 1–2, p. 13.Google Scholar
Cuffey, R.J., and Fine, R.L., 2005, The largest known fossil bryozoan reassembled from near Cincinnati: Ohio Geology, v. 2005, no. 1, p. 1, 3–4.Google Scholar
Cuffey, R.J., and Fine, R.L., 2006, Reassembled trepostomes and the search for the largest bryozoan colonies: International Bryozoology Association Bulletin, v. 2, no. 1, p. 13–15.Google Scholar
Cuffey, R.J., Davis, R.A., and Utgaard, J.E., 2002, The Cincinnati paleobryozoologists, in Wyse Jackson, P.N., and Spencer Jones, M.E., eds., Annals of Bryozoology: Aspects of the History of Research on Bryozoans: Dublin, International Bryozoology Association, p. 59–79.Google Scholar
Cumings, E.R., 1904, Development of some Paleozoic Bryozoa: American Journal of Science, 4th Series, v. 17, no. 97, p. 49–78.Google Scholar
Daley, G.M., 2004, Environmentally controlled variation in shell size of Ambonychia Hall (Mollusca, Bivalvia) in the type Cincinnatian (Upper Ordovician): Palaios, v. 14, p. 520–529.Google Scholar
Dattilo, B.F., Brett, C.E., and Schramm, T.J., 2012, Tempestites in a teapot: Condensation-generated shell beds in the Upper Ordovician, Cincinnati Arch, USA: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 367–368, p. 44–62.Google Scholar
d’Orbigny, A., 1850, Prodrome de Paléontologie Stratigraphique Universelle des Animaux Mollusques et Rayonnés faisant suite au Cours élémentaire de paléontologie et géologie stratigraphiques Vol. II: Paris, Masson.Google Scholar
Erickson, J.M., and Bouchard, T.D., 2003, Description and interpretation of Sanctum laurentiensis, new ichnogenus and ichnospecies, a domichnium mined into late Ordovician (Cincinnatian) ramose bryozoan colonies: Journal of Paleontology, v. 77, p. 1002–1010.Google Scholar
Erickson, J.M., and Waugh, D.A., 2002, Colony morphologies and missed opportunities during the Cincinnatian (Late Ordovician) bryozoan radiation: Examples from Heterotrypa frondosa and Monticulipora mammulata , in Wyse Jackson, P.N., Buttler, C.J., and Spencer Jones, M.E., eds., Bryozoan Studies 2001: Lisse, Netherlands, Balkema, p. 101–107.Google Scholar
Filatov, M.V., Kaandorp, J.A., Postma, M., van Liere, R., Kruszyński, K.J., Vermeij, M.J.A., Streekstra, G.J., and Bak, R.P.M., 2010, A comparison between coral colonies of the genus Madracis and simulated forms: Proceedings of the Royal Society of London, Series B, Biological Sciences, v. 277, no. 1700, p. 3555–3561.Google Scholar
Fleury, V., Gouyet, J.-F., and Léonetti, M., 2001, Branching in Nature: Dynamics and Morphogenesis of Branching Structures, from Cell to River Networks: Berlin, Springer-Verlag, 476 p.Google Scholar
Franco, M., 1986, The influences of neighbours on the growth of modular organisms with an example from trees: Philosophical Transactions of the Royal Society of London, Series B, Biological Sciences, v. 313, p. 209–225.Google Scholar
Gould, S.J., 2002, The Structure of Evolutionary Theory: Cambridge, MA, Belknap.Google Scholar
Hageman, S.J., Bone, Y., McGowran, B., and James, N.P., 1997, Bryozoan colonial growth forms as paleoenvironmental indicators: Evaluation of methodology: Palaios, v. 12, p. 405–419.Google Scholar
Hageman, S.J., Wyse Jackson, P.N., Abernethy, A.R., and Steinthorsdottir, M., 2011, Calendar scale, environmental variation preserved in the skeletal phenotype of a fossil bryozoan (Rhombopora blakei n. sp.), from the Mississippian of Ireland: Journal of Paleontology, v. 85, p. 853–870.Google Scholar
Håkansson, E., and Thomsen, E., 2001, Asexual propagation in cheilostome Bryozoa, in Jackson, J.B.C., Lidgard, S., and McKinney F.K., eds., Evolutionary Patterns: Growth, Form and Tempo in the Fossil Record: Chicago, University of Chicago Press, p. 326–347.Google Scholar
Harmelin, J.G., 1973, Morphological variations and ecology of the Recent cyclostome bryozoan ‘Idmonea’ atlantica from the Mediterranean, in Larwood, G.P., ed., Living and Fossil Bryozoa: London, Academic Press, p. 95–106.Google Scholar
Harper, J.L., Rosen, B.R., and White, J., eds., 1986, The Growth and Form of Modular Organisms: London, Royal Society of London, 250 p.Google Scholar
Hickey, D.R., 1988, Bryozoan astogeny and evolutionary novelties: Their role in the origin and systematics of the Ordovician monticuliporid trepostome genus Peronopora : Journal of Paleontology, v. 62, p. 180–203.Google Scholar
Holland, S.M., 1993, Sequence stratigraphy of a carbonate-clastic ramp: The Cincinnatian Series (Upper Ordovician) in its type area: Geological Society of America Bulletin, v. 105, p. 306–322.Google Scholar
Holland, S.M., 1997, Using time/environment analysis to recognize faunal events in the Upper Ordovician of the Cincinnati Arch, in Brett, C.E., and Baird, G.C., eds., Paleontological Events: Stratigraphic, Ecological, and Evolutionary Implications: New York, Columbia University Press, p. 309–334.Google Scholar
Holland, S.M., and Patzkowsky, M.E., 1996, Sequence stratigraphy and long-term paleoceanographic change in the Middle and Upper Ordovician of the eastern United States: Geological Society of America Special Papers, no. 306, p. 117–129.Google Scholar
Horton, R.E., 1945, Erosional development of streams and their drainage basins: Hydrophysical approach to quantitative morphology: Geological Society America Bulletin, v. 56, p. 275–370.Google Scholar
Jahnert, R.J., and Collins, L.B., 2012, Characteristics, distribution and morphogenesis of subtidal microbial systems in Shark Bay, Australia: Marine Geology, v. 303–306, p. 115–136.Google Scholar
Kaandorp, J.A., 1999, Morphological analysis of growth forms of branching marine sessile organisms along environmental gradients: Marine Biology, v. 134, p. 295–306.Google Scholar
Karklins, O.L., 1984, Trepostome and cystoporate bryozoans from the Lexington Limestone and the Clays Ferry Formation (Middle and Upper Ordovician) of Kentucky: U.S. Geological Survey, Professional Paper, 1066-I, p. 1–105.Google Scholar
Key, M.M. Jr., 1987, Partitioning of morphologic variation across stability gradients in Upper Ordovician trepostomes, in Ross, J.R.P., ed., Bryozoa: Present and Past: Bellingham, Western Washington University, p. 145–152.Google Scholar
Key, M.M. Jr., 1990, Intracolony variation in skeletal growth rates in Paleozoic ramose trepostome bryozoans: Paleobiology, v. 16, p. 483–491.Google Scholar
Key, M.M. Jr., Wyse Jackson, P.N., Håkansson, E., Patterson, W.P., and Moore, M.D., 2005, Gigantism in Permian trepostomes from Greenland: Testing the algal symbiosis hypothesis using δ13C and δ18O values, in Moyano G., H.I., Cancino, J.M., and Wyse Jackson, P.N., eds., Bryozoan Studies 2004, Leiden, Netherlands, Balkema, p. 141–151.Google Scholar
Key, M.M. Jr., Schumacher, G.A., Babcock, L.E., Frey, R.C., Heimbrock, W.P., Felton, S.H., Cooper, D.L., Gibson, W.B., Scheid, D.G., and Schumacher, S.A., 2010, Paleoecology of commensal epizoans fouling Flexicalymene (Trilobita) from the Upper Ordovician, Cincinnati Arch region, USA: Journal of Paleontology, v. 84, p. 1121–1134.Google Scholar
Key, M.M. Jr., Wyse Jackson, P.N., and Vitiello, L.J., 2011, Stream channel network analysis applied to colony-wide feeding structures in a Permian bryozoan from Greenland: Paleobiology, v. 37, p. 287–302.Google Scholar
Kohrs, R.H., Brett, C.E., and O’Brien, N., 2008, Sedimentology of Upper Ordovician mudstones from the Cincinnati Arch region, Ohio/Kentucky: Toward a general model of mud event deposition, in McLaughlin, P.I., Brett, C.E., Holland, S.M., and Storrs, G.W., eds., Stratigraphic Renaissance in the Cincinnati Arch—Implications for Upper Ordovician Paleontology and Paleoecology: Cincinnati, Cincinnati Museum Center, p. 87–109.Google Scholar
Leopold, L.B., 1971, Trees and streams: The efficiency of branching patterns: Journal of Theoretical Biology, v. 31, p. 339–354.Google Scholar
Madsen, L., 1994, Bryozoans from the Upper Palaeozoic Sequence in the Wandel Sea Basin, North Greenland: Wandel Sea Basin: Basin Analysis Scientific Report, v. 6, p. 1–18.Google Scholar
Madsen, L., and Håkansson, E., 1989, Upper Palaeozoic bryozoans from the Wandel Sea Basin, North Greenland: Rapport Grønlands Geologiske Undersøgelse, v. 144, p. 43–52.Google Scholar
McKinney, F.K., 1971, Trepostomatous Ectoprocta (Bryozoa) from the lower Chickamauga Group (Middle Ordovician), Wills Valley, Alabama: Bulletins of American Paleontology, v. 60, no. 267, p. 195–337.Google Scholar
McKinney, F.K., and Jackson, J.B.C., 1991, Bryozoan Evolution: Chicago, University of Chicago Press, 238 p.Google Scholar
McLaughlin, P.I., Brett, C.E., Holland, S.M., and Storrs, G.W., eds., 2008, Stratigraphic Renaissance in the Cincinnati Arch—Implications for Upper Ordovician Paleontology and Paleoecology: Cincinnati, Cincinnati Museum Center, 279 p.Google Scholar
Meyer, D.L., Davis, R.A., and Holland, S.M., 2009, A Sea Without Fish—Life in the Ordovician Sea of the Cincinnati Region: Bloomington, Indiana University Press, 368 p.Google Scholar
Milne-Edwards, H., and Haime, J., 1851, Monographie des polypiers fossiles des terrains Paléozoiques: Archives du Muséum d’Histoire Naturalle (Paris), v. 5, p. 1–502.Google Scholar
Minoletti O., M.L., Boerner, R.E.J., and Cochrane, K.E., 1995, Bifurcation ratio, internode lengths and branching patterns in Cornus florida L. (Cornaceae), a forest understory tree from eastern North America: Agro-ciencia, v. 11, no. 2, p. 203–210.Google Scholar
Mitton, J.B., 1985, So grows the tree: Natural History, v. 1, p. 58–65.Google Scholar
Nicholson, H.A., 1874, Description of species of Chaetetes from the lower Silurian rocks of North America: Quarterly Journal of the Geological Society of London, v. XXX, p. 499–515.Google Scholar
Nicholson, H.A., 1881, On the Structure and Affinities of the Genus Monticulipora and its Subgenera, with Critical Descriptions of Illustrative Species: Edinburgh, William Blackwood and Sons.Google Scholar
Niklas, K.J., 1986, Computer simulations of branching-patterns and their implications on the evolution of plants: Lectures on Mathematics in the Life Sciences, v. 18, p. 1–47.Google Scholar
Ohio Department of Transportation, 2011, Rock Slope Design Guide: Columbus, Ohio.gov, 56 p.Google Scholar
Oohata, S., and Shidei, T., 1971, Studies on the branching structure of trees I. Bifurcation ratio of trees in Horton’s Law: Japanese Journal of Ecology, v. 21, p. 7–14.Google Scholar
Oster, G., and Alberch, P., 1982, Evolution and bifurcation of developmental programs: Evolution, v. 36, p. 444–459.Google Scholar
Pachut, J.F., and Anstey, R.L., 1979, A developmental explanation of stability-diversity-variation hypotheses: Morphogenetic regulation in Ordovician bryozoan colonies: Paleobiology, v. 5, p. 168–187.Google Scholar
Pachut, J.F., and Fisherkeller, M.M., 2002, Changes in colonial development, intraspecific heterochrony, morphological integration, and character heritabilities in two populations of the bryozoan species Batostoma jamesi from the Kope Formation (Upper Ordovician, Cincinnatian): Journal of Paleontology, v. 76, p. 197–210.Google Scholar
Reid, C.M., 2003, Permian Bryozoa of Tasmania and New South Wales: Systematics and their use in Tasmanian biostratigraphy: Association of Australasian Palaeontologists, Memoir, v. 28, p. 1–133.Google Scholar
Reid, C.M., 2010, Environmental controls on the distribution of late Paleozoic bryozoan colony morphotypes: An example from the Permian of Tasmania, Australia: Palaios, v. 25, p. 692–702.Google Scholar
Ross, J.R.P., 1984, Palaeoecology of Ordovician Bryozoa: Palaeontological Contributions from the University of Oslo, v. 295, p. 141–148.Google Scholar
Ross, J.R.P., and Ross, C.A., 2002, Bryozoans in Ordovician depositional sequences, Cincinnati Arch region, USA, in Wyse Jackson, P.N., Buttler, C.J., and Spencer Jones, M.E., eds., Bryozoan Studies 2001: Lisse, Netherlands, Balkema, p. 261–274.Google Scholar
Sánchez, J.A., Lasker, H.R., Nepomuceno, E.G., Sánchez, J.D., and Woldenberg, M.J., 2004, Branching and self-organization in marine modular colonial organisms: A model: The American Naturalist, v. 163, no. 3, p. E24–E39.Google Scholar
Schopf, T.J.M., 1969, Paleoecology of ectoprocts (bryozoans): Journal of Paleontology, v. 43, p. 234–244.Google Scholar
Seilacher, A., Reif, W.E., and Westphal, F., 1985, Sedimentological, ecological, and temporal patterns of fossil Lagerstätten: Philosophical Transactions of the Royal Society of London, Series B, Biological Sciences, v. 311, p. 5–23.Google Scholar
Shreve, R.L., 1967, Infinite typologically random channel networks: Journal of Geology, v. 75, p. 178–186.Google Scholar
Sigler, L., 2002, Fibonacci’s Liber Abaci: A Translation into Modern English of Leonardo Pisano’s Book of Calculation: New York, Springer, 636 p.Google Scholar
Singh, R.J., 1979, Trepostomatous bryozoan fauna from the Bellevue Limestone, Upper Ordovician, in the Tri-State area of Ohio, Indiana and Kentucky: Bulletins of American Paleontology, v. 76, p. 159–288.Google Scholar
Smith, A.M., 1995, Palaeoenvironmental interpretation using bryozoans: A review, in Bosence, D.W.J., and Allison, P.A., eds., Marine Palaeoenvironmental Analysis from Fossils: Geological Society of London, Special Publications, v. 83, p. 231–243.Google Scholar
Smrecak, T.A., and Brett, C.E., 2014, Establishing patterns in sclerobiont distribution in a Late Ordovician (Cincinnatian) depth gradient: Toward a sclerobiofacies model: Palaios, v. 29, p. 74–85.Google Scholar
Stach, L.W., 1935, Growth variation in bryozoa cheilostomata: Annals and Magazine of Natural History, Series 10, v. 16, no. 96, p. 645–647.Google Scholar
Stach, L.W., 1936, Correlation of zoarial form with habitat: Journal of Geology, v. 44, p. 60–65.Google Scholar
Steingraeber, D.A., and Waller, D.M., 1986, Non-stationarity of tree branching patterns and bifurcation ratios: Proceedings of the Royal Society of London, Series B, Biological Sciences, v. 228, p. 187–194.Google Scholar
Strahler, A.N., 1957, Quantitative analysis of watershed geomorphology: American Geophysical Union Transactions, v. 38, p. 913–920.Google Scholar
Tarara, J.M., Ferguson, J.C., Hoheisel, G.-A., and Perez Peña, J.E., 2005, Asymmetrical canopy architecture due to prevailing wind direction and row orientation creates an imbalance in irradiance at the fruiting zone of grapevines: Agricultural and Forest Meteorology, v. 135, p. 144–155.Google Scholar
Tuckey, M.E., 1990, Biogeography of Ordovician bryozoans: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 77, p. 91–126.Google Scholar
Ulrich, E.O., 1882, American Palaeozoic Bryozoa: Journal of the Cincinnati Society of Natural History, v. 5, p. 232–257.Google Scholar
Ulrich, E.O., 1883, American Palaeozoic Bryozoa: Journal of the Cincinnati Society of Natural History, v. 6, p. 245–279.Google Scholar
Utgaard, J.E., and Perry, T.G., 1964, Trepostomatous bryozoan fauna of the upper part of the Whitewater Formation (Cincinnatian) of eastern Indiana and western Ohio: Indiana Department of Conservation Geological Survey Bulletin, v. 33, p. 1–111.Google Scholar
Waugh, D.A., and Erickson, J.M., 2002, Functional morphology of the anastomosing frondose growth form reported in Heterotrypa frondosa (d’Orbigny) (Bryozoa: Trepostomata) from the Cincinnatian (Late Ordovician) of Ohio, in Wyse Jackson, P.N., Buttler, C.J., and Spencer Jones, M.E., eds., Bryozoan Studies 2001: Lisse, Netherlands, Balkema, p. 331–338.Google Scholar
Waugh, D.A., Erickson, J.M., and Crawford, R.S., 2005, Two growth forms of Heterotrypa Nicholson, 1879 (Bryozoan: Trepostomata) from the type-Cincinnatian: Putting the pieces back together: The Compass, v. 78, no. 3, p. 97–112.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, v. 61, p. 1455–1465.Google Scholar
Whitney, G.G., 1976, The bifurcation ratio as an indicator of adaptive strategy in woody plant species: Bulletin of the Torrey Botanical Club, v. 103, no. 2, p. 67–72.Google Scholar
Wyse Jackson, P.N., and Key, M.M. Jr., 2007, Borings in trepostome bryozoans from the Ordovician of Estonia: Two genera produced by a single maker, a case of host morphology control: Lethaia, v. 40, p. 237–252.Google Scholar
Wyse Jackson, P.N., Bancroft, A.J., and Somerville, I.D., 1991, Bryozoan zonation in a trepostome-dominated buildup from the lower Carboniferous of North Wales, in Bigey, F.P., ed., Bryozoaires Actuels et Fossiles: Bryozoa Living and Fossil: Bulletin de la Société des Sciences Naturelles de l’Ouest de la France. Mémoire HS, v. 1, p. 551–559.Google Scholar
Wyse Jackson, P.N., Key, M.M. Jr., and Coakley, S.P., 2014, Epizoozoan trepostome bryozoans on nautiloids from the Late Ordovician (Katian) of the Cincinnati Arch region, U.S.A.: An assessment of growth, form and water flow dynamics: Journal of Paleontology, v. 88, p. 475–487.Google Scholar
Young, T.P., and Perkocha, V., 1994, Treefalls, crown asymmetry, and buttresses: Journal of Ecology, v. 82, p. 319–324.Google Scholar