Size variation in chewing lice <Emphasis Type="Italic">Docophorulus coarctatus</Emphasis>: how host size and louse population density vary together |
| |
Authors: | Piotr Tryjanowski Anetta Szczykutowicz Zbigniew Adamski |
| |
Institution: | (1) Department of Behavioural Ecology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland;(2) Department of Animal Taxonomy and Ecology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland;(3) Electron and Confocal Microscope Laboratory, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland |
| |
Abstract: | Chewing lice of the species Docophorulus coarctatus were extracted from museum specimens of their host, the great grey shrike Lanius excubitor, by combing feathers from 36 freshly shot birds (shot between 1962 and 1974), and samples of ten individual lice (five female,
five male) were randomly collected for measurements from each bird. Female lice were bigger than males for all studied measurements
(P < 0.001 in all cases), although the size of both sexes obtained from individual hosts was positively correlated. The overall
size of lice (derived from a principal components analysis) was positively correlated with the overall size of the avian host,
and also with the population density of lice on the individual host. We suggest that variation in louse morphology is due
to differences in selection pressure exerted by each host and by intraspecific competition due to conspecifics. This is, to
the best of our knowledge, the first evidence that Harrison’s rule (parasites on larger host species are often bigger than
those on smaller hosts) not only works in a multispecies comparison but also within a single host–single parasite system as
well. |
| |
Keywords: | Body size Coevolution Density dependence Harrison’ s rule Parasites |
本文献已被 SpringerLink 等数据库收录! |
|