title: Dispersal distance is influenced by parental and grand-parental density.
abstract: Non-genetic transmission of information across generations, so-called parental effects, can have significant impacts on offspring morphology, physiology, behaviour and life-history traits. In previous experimental work using the two-spotted spider mite Tetranychus urticae Koch, we demonstrated that dispersal distances increase with local density and levels of genetic relatedness. We here show that manipulation of parental and grand-parental density has a significant effect on offspring dispersal distance, of the same order of magnitude as manipulation of offspring density. We demonstrate that offspring exposed to the same density disperse further if they were born to parents exposed to higher density compared with parents exposed to low density. Offspring dispersal distance also increases when grand-parents were exposed to higher density, except for offspring exposed to low densities, which disperse at shorter distances whatever the grand-parental density. We also show that offspring from mothers exposed to higher densities were overall larger, which suggests that parents in high densities invest more in individual offspring, enabling them to disperse further. We propose that our findings should be included in models investigating the spread rate of invasive species or when predicting the success of conservation measures of species attempting to track changing climates.
authors.affiliation: Evolutionary Ecology and Genetics Group, Biodiversity Research Centre, Earth and Life Institute, Académie Louvain, Croix du Sud 4, 1348 Louvain-la-Neuve, Belgium Institut des Sciences de l'Evolution, Université Montpellier 2, CNRS, CC65, Place Eugène Bataillon, 34095 Montpellier, France ebitume@gmail.com.
authors.forename: E V
authors.initials: EV
authors.lastname: Bitume
authors.affiliation: Terrestrial Ecology Unit, Ghent University, Ghent, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Bonte
authors.affiliation: Institut des Sciences de l'Evolution, Université Montpellier 2, CNRS, CC65, Place Eugène Bataillon, 34095 Montpellier, France.
authors.forename: O
authors.initials: O
authors.lastname: Ronce
authors.affiliation: Institut des Sciences de l'Evolution, Université Montpellier 2, CNRS, CC65, Place Eugène Bataillon, 34095 Montpellier, France.
authors.forename: I
authors.initials: I
authors.lastname: Olivieri
authors.affiliation: Evolutionary Ecology and Genetics Group, Biodiversity Research Centre, Earth and Life Institute, Académie Louvain, Croix du Sud 4, 1348 Louvain-la-Neuve, Belgium.
authors.forename: C M
authors.initials: CM
authors.lastname: Nieberding
mesh_terms: D063147:Animal Distribution / Q000502:physiology*; D000818:Animals; D049628:Body Size; D005260:Female; D008018:Life Cycle Stages; D008297:Male; D018811:Maternal Exposure; D010641:Phenotype; D011156:Population Density; D040102:Tetranychidae / Q000502:physiology*
keywords: conditional dispersal; density; invasion; maternal effects; plasticity