Biology subjects

Dingemanse, N. J.

Publications and source records attributed to Dingemanse, N. J..

3 recordsLinked to original sources

bioRxiv2020

Tick infestation probability increases with human recreational pressure and exploratory behaviour in wild great tits (Parus major)

Ticks are parasites that feed on the blood of various vertebrate hosts, including many species of bird. Birds can disperse ticks over short and long distances, therefore impacting tick population dynamics. The likelihood that birds attract ticks should depend on their behaviour and the environment. We studied various key ecological variables (breeding density, human disturbance) and phenotypic traits (exploratory behaviour; body condition) proposed to predict tick burden in great tits (Parus major). Our study spanned over three years and 12 human-recreated plots, equipped with nest-boxes in southern Germany. Adult breeders were assessed for exploratory behaviour, tick burden, and body condition. For each plot, human disturbance was quantified as a human recreational pressure index during biweekly nest box inspections by scoring the number of recreants using the plots. Infestation probability but not tick burden increased with exploratory behaviour. We also found moderate support for a positive effect of recreational pressure on infestation probability. Further, body condition negatively predicted tick burden. Individuals were repeatable in tick burden across years. Our study implies that infestation probability and tick burden are governed by distinct ecological and phenotypic drivers. Our findings also highlight the importance of incorporating ecological and individual variation in host phenotypes to predict spatiotemporal distributions of ticks in nature. (207/250-word limit) Lay SummaryTicks use many birds as hosts, but why do some individuals have more or fewer ticks? Using a data collected over three years on great tit adults inhabiting 12 different nest-box plots, we showed that more explorative birds and those in highly recreated habitats were more likely to be infested with ticks. Exploratory behaviour and human disturbance could modify great tit habitat choice and, therefore, impact how often a birds and ticks encounter each other.

ecology↗

bioRxiv2019

Density-dependent costs and benefits of male mating success in a wild insect

O_LISocial environments are important determinant of fitness, particularly when same-sex local densities shape both mating success and survival costs.\nC_LIO_LIWe studied how mating success varied across a range of naturally occurring local male densities in wild field cricket males, Gryllus campestris, monitored by using fully automated RFID-surveillance system. We predicted that mating success as a function of local density follow a concave pattern predicted by the Allee-effect theory. As increasing density should reduce per capita predation and parasitism risk, we predicted that males generally having high mating success in low (versus high) local density live less long. Finally, we predicted that males on average occurred in local densities where their mating success is highest.\nC_LIO_LIMale mating success followed a density-dependent pattern predicted by the Allee-effect theory. Males also differed in the local density where their mating success was highest. This variation explained longevity and total fitness: males with high mating success in low local density lived longer and had higher total mating success. Finally, we found no evidence of males occupying local densities in which their mating success is highest.\nC_LIO_LIOur study suggest that density-dependent plasticity in mating success is under selection: males having high mating success in low density, but low mating success in high density, lived longer and had higher overall mating success. We thus provide novel insights, with unseen detail, about individual differences in density-dependent mating success and, costs and benefits related to variation in mating success in the wild. Finally, our study also highlights that specific statistical approaches are needed to firmly study the costs and benefits associated with the traits that are repeatedly expressed across range of environments.\nC_LI

evolutionary biology↗

bioRxiv2019

The great tit HapMap project: a continental-scale analysis of genomic variation in a songbird

A major aim of evolutionary biology is to understand why patterns of genomic diversity vary among populations and species. Large-scale genomic studies of widespread species are useful for studying how the environment and demographic history shape patterns of genomic divergence, and with the continually decreasing cost of sequencing and genotyping, such studies are now becoming feasible. Here, we carry out one of the most geographically comprehensive surveys of genomic variation in a wild vertebrate to date; the great tit (Parus major) HapMap project. We screened ca 500,000 SNP markers across 647 individuals from 29 populations, spanning almost the entire geographic range of the European great tit subspecies. We found that genome-wide variation was consistent with a recent colonisation across Europe from a single refugium in South-East Europe, with bottlenecks and reduced genetic diversity in island populations. Differentiation across the genome was highly heterogeneous, with clear "islands of differentiation" even among populations with very low levels of genome-wide differentiation. Low local recombination rate in the genome was a strong predictor of high local genomic differentiation (FST), especially in island and peripheral mainland populations, suggesting that the interplay between genetic drift and recombination is a key driver of highly heterogeneous differentiation landscapes. We also detected genomic outlier regions that were confined to one or more peripheral great tit populations, most likely as a result of recent directional selection at the range edges of this species. Haplotype-based measures of selection were also related to recombination rate, albeit less strongly, and highlighted population-specific sweeps that likely resulted from positive selection. These regions under positive selection contained candidate genes associated with morphology, thermal adaptation and colouration, providing promising avenues for future investigation. Our study highlights how comprehensive screens of genomic variation in wild organisms can provide unique insights into evolution.

evolutionary biology↗