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Title: Food web structure selects for parasite host range
Complex life cycle parasites, including helminths, use intermediate hosts for development and definitive hosts for reproduction, with interactions between the two host types governed by food web structure. I study how a parasite's intermediate host range is controlled by the diet breadth of definitive host species and the cost of parasite generalism, a putative fitness cost that assumes host range trades off against fitness derived from a host species. In spite of such costs, a benefit to generalism may occur when the definitive host exhibits a large diet breadth, enhancing transmission of generalist parasites via consumption of a broad array of infected intermediate hosts. I develop a simple theoretical model to demonstrate how different host range infection strategies are differentially selected for across a gradient of definitive host diet breadth according to the cost of generalism. I then use a parasitic helminth–host database in conjunction with a food web database to show that diet breadth of definitive hosts promotes generalist infection strategies at the intermediate host level, indicating relatively low costs of parasite generalism among helminths.  more » « less
Award ID(s):
1754255
PAR ID:
10179897
Author(s) / Creator(s):
Date Published:
Journal Name:
Proceedings of the Royal Society B: Biological Sciences
Volume:
286
Issue:
1908
ISSN:
0962-8452
Page Range / eLocation ID:
20191277
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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