de.mpg.escidoc.pubman.appbase.FacesBean
English
 
Help Guide Disclaimer Contact us Login
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

The trophic vacuum and the evolution of complex life cycles in trophically transmitted helminths

MPS-Authors
http://pubman.mpdl.mpg.de/cone/persons/resource/persons56593

Benesh,  Daniel P.
Department Evolutionary Ecology, Max Planck Institute for Evolutionary Biology, Max Planck Society;

Locator
There are no locators available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Benesh, D. P., Chubb, J. C., & Parker, G. A. (2014). The trophic vacuum and the evolution of complex life cycles in trophically transmitted helminths. Proceedings of the Royal Society B: Biological Sciences, 281(1793): 20141462. doi:10.1098/rspb.2014.1462.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0023-D83B-C
Abstract
Parasitic worms (helminths) frequently have complex life cycles in which they are transmitted trophically between two or more successive hosts. Sexual reproduction often takes place in high trophic-level (TL) vertebrates, where parasites can grow to large sizes with high fecundity. Direct infection of high TL hosts, while advantageous, may be unachievable for parasites constrained to transmit trophically, because helminth propagules are unlikely to be ingested by large predators. Lack of niche overlap between propagule and definitive host (the trophic transmission vacuum) may explain the origin and/or maintenance of intermediate hosts, which overcome this transmission barrier. We show that nematodes infecting high TL definitive hosts tend to have more successive hosts in their life cycles. This relationship was modest, though, driven mainly by the minimum TL of hosts, suggesting that the shortest trophic chains leading to a host define the boundaries of the transmission vacuum. We also show that alternative modes of transmission, like host penetration, allow nematodes to reach high TLs without intermediate hosts. We suggest that widespread omnivory as well as parasite adaptations to increase transmission probably reduce, but do not eliminate, the barriers to the transmission of helminths through the food web.