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The position of graptolites within Lower Palaeozoic planktic ecosystems.

Underwood, Charlie J. (1993) The position of graptolites within Lower Palaeozoic planktic ecosystems. Lethaia 26 , pp. 189-202. ISSN 0024-1164.

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Official URL: http://dx.doi.org/10.1111/j.1502-3931.1993.tb01517...

Abstract

An integrated approach has been used to assess the palaeoecology of graptolites both as a discrete group and also as a part of the biota present within Ordovician and Silurian planktic realms. Study of the functional morphology of graptolites and comparisons with recent ecological analogues demonstrates that graptolites most probably filled a variety of niches as primary consumers, with modes of life related to the colony morphotype. Graptolite coloniality was extremely ordered, lacking any close morphological analogues in Recent faunas. To obtain maximum functional efficiency, graptolites would have needed varying degrees of coordinated automobility. A change in lifestyle related to ontogenetic changes was prevalent within many graptolite groups. Differing lifestyle was reflected by differing reproductive strategies, with synrhabdosomes most likely being a method for rapid asexual reproduction. Direct evidence in the form of graptolithophage 'coprolitic' bodies, as well as indirect evidence in the form of probable defensive adaptations, indicate that graptolites comprised a food item for a variety of predators. Graptolites were also hosts to a variety of parasitic organisms and provided an important nutrient source for scavenging organisms.

Item Type: Article
Additional Information: C. Underwood is now a lecturer at Birkbeck
Keyword(s) / Subject(s): Feeding, graptolites, hydrodynamics, ontogeny, parasitism, palaeoecology, plankton, predation, Silurian, Ordovician
School or Research Centre: Birkbeck Schools and Research Centres > School of Science > Earth and Planetary Sciences
Depositing User: Charlie Underwood
Date Deposited: 11 May 2005
Last Modified: 17 Apr 2013 12:32
URI: http://eprints.bbk.ac.uk/id/eprint/124

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