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Spatial analyses of Ediacaran communities at Mistaken Point

Published online by Cambridge University Press:  26 January 2018

Emily G. Mitchell
Affiliation:
Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, United Kingdom. E-mail: ek338@cam.ac.uk, njb1005@cam.ac.uk
Nicholas J. Butterfield
Affiliation:
Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, United Kingdom. E-mail: ek338@cam.ac.uk, njb1005@cam.ac.uk

Abstract

Bedding-plane assemblages of Ediacaran fossils from Mistaken Point, Newfoundland, are among the oldest known records of complex multicellular life on Earth (dated to ~565 Ma). The in situ preservation of these sessile but otherwise deeply enigmatic organisms means that statistical analyses of specimen positions can be used to illuminate their underlying ecological dynamics, including the interactions between taxa.

Fossil assemblages on Mistaken Point D and E surfaces were mapped to millimeter accuracy using differentiated GPS. Spatial correlations between 10 well-defined taxa (Bradgatia, Charniid, Charniodiscus, Fractofusus, Ivesheadiomorphs, Lobate Discs, Pectinifrons, Plumeropriscum, Hiemalora, and Thectardis) were identified using Bayesian network inference (BNI), and then described and analyzed using spatial point-process analysis. BNI found that the E-surface community had a complex web of interactions and associations between taxa, with all but one taxon (Thectardis) interacting with at least one other. The unique spatial distribution of Thectardis supports previous, morphology-based arguments for its fundamentally distinct nature. BNI revealed that the D-surface community showed no interspecific interactions or associations, a pattern consistent with a homogeneous environment.

On the E surface, all six of the abundant taxonomic groups (Fractofusus, Bradgatia, Charniid, Charniodiscus, Thectardis, and Plumeropriscum) were found to have a unique set of interactions with other taxa, reflecting a broad range of underlying ecological responses. Four instances of habitat associations were detected between taxa, of which two (CharniodiscusPlumeropriscum and PlumeropriscumFractofusus) led to weak competition for resources. One case of preemptive competition between Charniid and Lobate Discs was detected. There were no instances of interspecific facilitation. Ivesheadiomorph interactions mirror those of Fractofusus and Charniodiscus, identifying them as a form-taxonomic grouping of degradationally homogenized taphomorphs. The absence of increased fossil abundance in proximity to these taphomorphs argues against scavenging or saprophytic behaviors dominating the E-surface community.

Type
Articles
Copyright
Copyright © 2018 The Paleontological Society. All rights reserved 

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References

Literature Cited

Agarwal, S. K. 2008. Fundamentals of ecology. APH Publishing, New Delhi.Google Scholar
Antcliffe, J. B., Callow, R. H. T., and Brasier, M. D.. 2014. Giving the early fossil record of sponges a squeeze. Biological Reviews 89:9721004.Google Scholar
Antcliffe, J. B., Hancy, A. D., and Brasier, M. D.. 2015. A new ecological model for the ∼565 Ma Ediacaran biota of Mistaken Point, Newfoundland. Precambrian Research 268:227242.Google Scholar
Baddeley, A., Rubak, E., and Turner, R.. 2015. Spatial point patterns. methodology and applications with R. CRC, Boca Raton, Fla.Google Scholar
Benus, A. P. 1988. Sedimentological context of a deep-water Ediacaran fauna (Mistaken Point, Avalon Zone, eastern Newfoundland). In E. Landing, G. M. Narbonne, and P. Myrow, eds. Trace fossils, small shelly fossils and the Precambrian–Cambrian boundary. New York State Museum and Geological Survey Bulletin 463:8–9. Albany, N.Y.Google Scholar
Brasier, M. D., Antcliffe, J. B., and Liu, A. G.. 2012. The architecture of Ediacaran fronds. Palaeontology 55:11051124.Google Scholar
Bertness, M.D., and Leonard, G.H.. 1997. The role of positive interactions in communities: lessons from intertidal habitats. Ecology 78:19761989.Google Scholar
Brooker, R. W., et al. 2008. Facilitation in plant communities: the past, the present, and the future. Journal of Ecology 96:1834.Google Scholar
Bruno, J. F., Stachowicz, J. J., and Bertness, M. D.. 2003. Inclusion of facilitation into ecological theory. Trends in Ecology and Evolution 18:119125.Google Scholar
Budd, G. E., and Jensen, S.. 2017. The origin of the animals and a “Savannah” hypothesis for early bilaterian evolution. Biological Reviews 92:446473.Google Scholar
Calle, S. R. 2010. Ecological aspects of sponges in mesophotic coral ecosystems. Ph.D. dissertation. University of Puerto Rico, Mayagüez. Masters Abstracts International 49(3).Google Scholar
Carlon, D. B., and Olson, R. R.. 1993. Larval dispersal distance as an explanation for adult spatial pattern in two Caribbean reef corals. Journal of Experimental Marine Biology and Ecology 173:247263.Google Scholar
Clapham, M. E., Narbonne, G. M., and Gehling, J. G.. 2003. Paleoecology of the oldest known animal communities: Ediacaran assemblages at Mistaken Point, Newfoundland. Paleobiology 29:527544.Google Scholar
Clapham, M. E., Narbonne, G. M., Gehling, J. G., Greentree, C., and Anderson, M. M.. 2004. Thectardis avalonensis: a new Ediacaran fossil from the Mistaken Point biota, Newfoundland. Journal of Paleontology 78:10311036.Google Scholar
Dale, M.R. T., and Fortin, M. J.. 2014. Spatial analysis: a guide for ecologists. Cambridge University Press, New York.Google Scholar
Darroch, S. A. F., Laflamme, M., and Clapham, M. E.. 2013. Population structure of the oldest known macroscopic communities from Mistaken Point, Newfoundland. Paleobiology 39:591608.Google Scholar
Dececchi, T. A., Narbonne, G. M., Greentree, C., and Laflamme, M.. 2017. Relating Ediacaran fronds. Paleobiology 43:171180.Google Scholar
De Luis, M., Raventós, J., Wiegand, T., and González-Hidalgo, J. C.. 2008. Temporal and spatial differentiation in seedling emergence may promote species coexistence in Mediterranean fire-prone ecosystems. Ecography 31:620629.Google Scholar
Dickie, I. A., Schnitzer, S. A., Reich, P. B., and Hobbie, S. E.. 2005. Spatially disjunct effects of co-occurring competition and facilitation. Ecology Letters 8:11911200.Google Scholar
Diggle, P. 2003. Statistical analysis of spatial point patterns, 2nd ed. Arnold, London.Google Scholar
Dufour, S. C., and McIlroy, D.. 2017. Ediacaran pre-placozoan diploblasts in the Avalonian biota: the role of chemosynthesis in the evolution of early animal life. Geological Society of London Special Publication 448:211219.Google Scholar
Engel, S., and Pawlik, J. R.. 2000. Allelopathic activities of sponge extracts. Marine Ecology Progress Series 207:273282.Google Scholar
Fraley, C., Raftery, A. E., and Scrucca, L.. 2012). mclust version 4 for R: normal mixture modeling for model-based clustering, classification, and density estimation. Technical Report No. 597. Department of Statistics, University of Washington, Seattle.Google Scholar
Futuyma, D. J., and Agrawal, A. A.. 2009. Macroevolution and the biological diversity of plants and herbivores. Proceedings of the National Academy of Sciences USA 106:18054–18061.Google Scholar
Getzin, S., Dean, Ch., He, F., Trofymow, J. A, Wiegand, K., and Wiegand, T.. 2006. Spatial patterns and competition of tree species in a Douglas-fir chronosequence on Vancouver Island. Ecography 29:671682.Google Scholar
Getzin, S., Wiegand, T. W., K., and He, F.. 2008. Heterogeneity influences spatial patterns and demographics in forest stands. Journal of Ecology 96:807820.Google Scholar
Goreaud, F., and Pélissier, R.. 2003. Avoiding misinterpretation of biotic interactions with the intertype K12-function: population independence vs. random labelling hypotheses. Journal of Vegetation Science 14:681692.Google Scholar
Grazhdankin, D. 2004. Patterns of distribution in the Ediacaran biotas: facies versus biogeography and evolution. Paleobiology 30:203221.Google Scholar
Greig-Smith, P. 1979. Pattern in vegetation. Journal of Ecology 67:755779.Google Scholar
Heckerman, D., Geiger, D., and Chickering, D. M.. 1995. Learning Bayesian networks: the combination of knowledge and statistical data. Machine Learning 20:197243.Google Scholar
Hereford, J. 2009. A quantitative survey of local adaptation and fitness trade-offs. American Naturalist 173:579588.Google Scholar
Hoyal Cuthill, J. F., and Conway Morris, S.. 2014). Fractal branching organizations of Ediacaran rangeomorph fronds reveal a lost Proterozoic body plan. Proceedings of the National Academy of Sciences USA 111:13122–13126.Google Scholar
Ichaso, A. A., Dalrymple, R. W., and Narbonne, G. M.. 2007. Paleoenvironmental and basin analysis of the late Neoproterozoic (Ediacaran) upper Conception and St. John’s groups, west Conception Bay, Newfoundland. Canadian Journal of Earth Sciences 44:2541.Google Scholar
Illian, J., Penttinen, A., Stoyan, H., and Stoyan, D.. 2008. Statistical analysis and modelling of spatial point patterns. Statistics in practice Vol. 70. Wiley, Chichester, U.K.Google Scholar
Jackson, J. B. C., and Buss, L.. 1975). Allelopathy and spatial competition among coral reef invertebrates. Proceedings of the National Academy of Sciences USA 72:5160–5163.Google Scholar
Jacquemyn, H., Endels, P., Honnay, O., and Wiegand, T.. 2010. Evaluating management interventions in small populations of a perennial herb Primula vulgaris using spatio-temporal analyses of point patterns. Journal of Applied Ecology 47:431440.Google Scholar
John, R., et al. 2007. Soil nutrients influence spatial distributions of tropical tree species. Proceedings of the National Academy of Sciences USA 104:864–869.Google Scholar
Jones, C. G., Lawton, J. H., and Shachak, M.. 1997. Positive and negative effects of organisms as physical ecosystem engineers. Ecology 78:19461957.Google Scholar
Kawecki, T. J., and Ebert, D.. 2004. Conceptual issues in local adaptation. Ecology Letters 7:12251241.Google Scholar
Kenchington, C. G., and Wilby, P. R. 2014). Of time and taphonomy: preservation in the Ediacaran. In M. Laflamme, J. D. Schiffbauer, and S. A. F. Darroch, eds. Reading and writing of the fossil record: preservational pathways to exceptional fossilization. Paleontological Society Papers 20:101–122.Google Scholar
Laflamme, M., Schiffbauer, J. D., and Narbonne, G. M.. 2011. Deep-water microbially induced sedimentary structures (MISS) in deep time: the Ediacaran fossil Ivesheadia. Microbial mats in siliciclastic depositional systems through time. SEPM Special Publication 101:111123.Google Scholar
Law, R., Illian, J., Burslem, D. F. R. P., Gratzer, G., Gunatilleke, C. V. S., and Gunatilleke, I. A. U. N.. 2009. Ecological information from spatial patterns of plants: insights from point process theory. Journal of Ecology 97:616628.Google Scholar
Lin, Y. C., Chang, L. W., Yang, K. C., Wang, H. H., and Sun, I. F.. 2011. Point patterns of tree distribution determined by habitat heterogeneity and dispersal limitation. Oecologia 165:175184.Google Scholar
Liang, Y., Guo, L. D., Du, X. J., and Ma, K. P.. 2007. Spatial structure and diversity of woody plants and ectomycorrhizal fungus sporocarps in a natural subtropical forest. Mycorrhiza 17:271.Google Scholar
Lingua, E., Cherubini, P., Motta, R., and Nola, P.. 2008. Spatial structure along an altitudinal gradient in the Italian central Alps suggests competition and facilitation among coniferous species. Journal of Vegetation Science 19:425436.Google Scholar
Liu, A. G. 2016. Framboidal pyrite shroud confirms the “death mask” model for moldic preservation of Ediacaran soft-bodied organisms. Palaios 31:259274.Google Scholar
Liu, A. G., Mcilroy, D., Antcliffe, J. B., and Brasier, M. D.. 2011. Effaced preservation in the Ediacara biota and its implications for the early macrofossil record. Palaeontology 54:607630.Google Scholar
Liu, A. G., McIlroy, D, Matthews, J. J., and Brasier, M. D.. 2012. A new assemblage of juvenile Ediacaran fronds from the Drook Formation, Newfoundland. Journal of the Geological Society 169:395403.Google Scholar
Liu, A. G., Kenchington, C. G., and Mitchell, E. G.. 2015. Remarkable insights into the paleoecology of the Avalonian Ediacaran macrobiota. Gondwana Research 27:13551380.Google Scholar
Magurran, A. E. 2013. Measuring biological diversity. Wiley, Oxford, U.K.Google Scholar
Mason, B., et al. 2003. Continuous cover forestry in British conifer forests. Forest Research Annual Report and Accounts 2004:3853.Google Scholar
Matthews, J. J., Liu, A. G., and McIlroy, D.. 2017. Post-fossilization processes and their implications for understanding Ediacaran macrofossil assemblages. Geological Society of London Special Publication 448:251269.Google Scholar
McCook, L., Jompa, J., and Diaz-Pulido, G.. 2001. Competition between corals and algae on coral reefs: a review of evidence and mechanisms. Coral Reefs 19:400417.Google Scholar
McIlroy, D., and Garton, M.. 2010. Realistic interpretation of ichnofabrics and palaeoecology of the pipe-rock biotope. Lethaia 43:420426.Google Scholar
Milns, I., Beale, C. M., and Smith, V. A.. 2010. Revealing ecological networks using Bayesian network inference algorithms. Ecology 91:18921899.Google Scholar
Mitchell, E. G., Kenchington, C. G., Liu, A. G., Matthews, J. J., and Butterfield, N. J.. 2015. Reconstructing the reproductive mode of an Ediacaran macro-organism. Nature 524:343.Google Scholar
Mitchell-Olds, T., and Schmitt, J.. 2006. Genetic mechanisms and evolutionary significance of natural variation in Arabidopsis . Nature 441:947.Google Scholar
Muko, S., Shimatani, I. K., and Nozawa, Y.. 2014. Spatial analyses for non-overlapping objects with size variations and their application to coral communities. Journal of Animal Ecology 83:980990.Google Scholar
Narbonne, G. M. 2004. Modular construction of early Ediacaran complex life forms. Science 305:11411144.Google Scholar
Raventós, J., Wiegand, T., and De Luis, M.. 2010. Evidence for the spatial segregation hypothesis: a test with nine year survivorship data in a Mediterranean shrubland. Ecology 91:21102120.Google Scholar
Seidler, T. G., and Plotkin, J. B.. 2006. Seed dispersal and spatial pattern in tropical trees. PLoS Biology 4:e344.Google Scholar
Seilacher, A., Buatois, L. A., and Mángano, M. G.. 2005. Trace fossils in the Ediacaran–Cambrian transition: behavioural diversification, ecological turnover and environmental shift. Palaeogeography, Palaeoclimatology, Palaeoecology 227:323356.Google Scholar
Smith, C. R., Glover, A. G., Treude, T., Higgs, N. D., and Amon, D. J.. 2015. Whale–fall ecosystems: recent insights into ecology, paleoecology, and evolution. Annual Review of Marine Science 7:571596.Google Scholar
Smith, V. A., Yu, J., Smulders, T. V., Hartemink, A. J., and Jarvis, E. D.. 2006. Computational inference of neural information flow networks. PLoS Computational Biology 2:e161.Google Scholar
Sobel, J. M., Chen, G. F., Watt, L. R., and Schemske, D. W.. 2010. The biology of speciation. Evolution 64:295315.Google Scholar
Sperling, E. A., Peterson, K. J., and Laflamme, M.. 2011. Rangeomorphs, Thectardis (Porifera?) and dissolved organic carbon in the Ediacaran oceans. Geobiology 9:2433.Google Scholar
Townsend, C. R., Begon, M., and Harper, J. L.. 2003. Essentials of ecology, 2nd ed. Blackwell Scientific, Oxford, U.K.Google Scholar
Velázquez, E., Kazmierczak, M., and Wiegand, T.. 2016. Spatial patterns of sapling mortality in a moist tropical forest: consistency with total density dependent effects. Oikos 125:872882.Google Scholar
Waggoner, B. 2003. The Ediacaran biotas in space and time. Integrative and Comparative Biology 43:104113.Google Scholar
Wang, X., et al. 2011. Spatial patterns of tree species richness in two temperate forests. Journal of Ecology 99:13821393.Google Scholar
Wiegand, T., and Moloney, K. A.. 2004. Rings, circles, and null-models for point pattern analysis in ecology. Oikos 104:209229.Google Scholar
Wiegand, T., and Moloney, K. A.. 2013. Handbook of spatial point-pattern analysis in ecology. CRC, Boca Raton, Fla.Google Scholar
Wiegand, T., Kissling, W. D., Cipriotti, P. A., and Aguiar, M. R.. 2006. Extending point pattern analysis for objects of finite size and irregular shape. Journal of Ecology 94:825837.Google Scholar
Wiegand, T., Gunatilleke, S., and Gunatilleke, N.. 2007a. Species associations in a heterogeneous Sri Lankan dipterocarp forest. American Naturalist 170:E77E95.Google Scholar
Wiegand, T., Gunatilleke, S., Gunatilleke, N., and Okuda, T.. 2007b. Analyzing the spatial structure of a Sri Lankan tree species with multiple scales of clustering. Ecology 88:30883102.Google Scholar
Wiegand, T., Martínez, I., and Huth, A.. 2009. Recruitment in tropical tree species: revealing complex spatial patterns. American Naturalist 174:E106E140.Google Scholar
Wiegand, T., Huth, A., Getzin, S., Wang, X., Hao, Z., Gunatilleke, C. V. S., and Gunatilleke, I. N.. 2012). Testing the independent species’ arrangement assertion made by theories of stochastic geometry of biodiversity. Proceedings of the Royal Society of London B 279. 10.1098/rspb.2012.0376.Google Scholar
Wilby, P. R., Carney, J. N., and Howe, M. P.A.. 2011. A rich Ediacaran assemblage from eastern Avalonia: evidence of early widespread diversity in the deep ocean. Geology 39:655658.Google Scholar
Willis, R. J. 2007. The history of allelopathy. Springer Science & Business Media, Dordrecht, Netherlands.Google Scholar
Wood, D. A., Dalrymple, R. W., Narbonne, G. M., Gehling, J. G., and Clapham, M. E.. 2003. Paleoenvironmental analysis of the late Neoproterozoic Mistaken Point and Trepassey formations, south-eastern Newfoundland. Canadian Journal of Earth Sciences 40:13751391.Google Scholar
Yu, J., Smith, V. A., Wang, P. P., Hartemink, A. J., and Jarvis, E. D.. 2004. Advances to Bayesian network inference for generating causal networks from observational biological data. Bioinformatics 20:35943603.Google Scholar