Faunal Diversity among Avian Parasite Assemblages: The Interaction of History, Ecology, and Biogeography in Marine Systems

• Main Author: Hoberg, Eric P.
• Format: Text
• Language: unknown
• Published: DigitalCommons@University of Nebraska - Lincoln 1996
• Subjects: Biodiversity; Ecology and Evolutionary Biology; Evolution; Marine Biology; Ornithology; Parasitology; Pacific; Southern Ocean
• Online Access: https://digitalcommons.unl.edu/parasitologyfacpubs/789; https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1800&context=parasitologyfacpubs

Systematics and parasite biodiversity provide power and predictability in broad studies of history, ecology and biogeography in marine systems. Parasitic helminths are elegant markers of contemporary and historical ecological relationships, geographic distribution and host-phylogeny. Complex life cycles of helminths are strongly correlated with intricate food-webs. Dependence on a series of intermediate, paratenic, and definitive hosts indicates that each parasite species represents an array of organisms within a community and tracks broadly and predictably across many trophic levels. Host and geographic ranges of parasites are historically constrained by genealogical and ecological associations, and these determinents interact resulting in characteristic parasite community structure. Generally, the parasite faunas of pelagic seabirds are depauperate, and these' are not indicative of relictual associations linking marine and terrestrial environments. Some core elements of the marine tapeworm fauna are archaic and potentially coevolved (Tetrabothriidae and seabird orders) whereas others have a more recent historical association emphasizing host switching with minimal cospeciation (Alcataenia spp. among Alcidae). In contrast, contemporary ecological determinants appear more significant as an influence on the distribution of digeneans, nematodes and acanthocephalans among marine birds. Ecologically discrete assemblages determined by foraging, prey selection, and distribution are indicated by patterns of parasite abundance, prevalence and host range across taxonomic, geographic and temporal scales. Thus, knowledge of the evolution of parasite-host assemblages provides direct estimates of the history of ecological associations and community development, and is indicative of the temporal continuity of trophic assemblages. Parasites constitute probes that can be applied directly to questions of contemporary diversity and the historical development of community structure. Concurrently, a predictive framework, with parasites as indicators, exists for elucidating the impacts of natural or anthropogenic perturbations to faunas and ecosystems. These concepts and phenomena are examined across a range of temporal and geographic scales extending from the North Pacific basin to the Southern Ocean. Parasitology offers the potential to achieve unique insights about ecological interactions and community structure over evolutionarily significant time frames.