Climate change is rapidly altering the environment and many species will need to genetically adapt their seasonal timing to keep up with these changes. Insect development rate is largely influenced... Show moreClimate change is rapidly altering the environment and many species will need to genetically adapt their seasonal timing to keep up with these changes. Insect development rate is largely influenced by temperature, but we know little about the mechanisms underlying the temperature sensitivity of development. Here, we investigate seasonal timing of egg hatching in the winter moth, one of the few species which has been found to genetically adapt to climate change, likely through selection on temperature sensitivity of egg development rate. To study when during development winter moth embryos are most sensitive to changes in ambient temperature, we gave eggs an increase or decrease in temperature at different moments during their development. We measured their developmental progression and time of egg hatching, and used fluorescence microscopy to construct a timeline of embryonic development for the winter moth. We found that egg development rate responded more strongly to temperature once embryos were in the fully extended germband stage. This is the phylotypic stage at which all insect embryos have developed a rudimentary nervous system. Furthermore, at this stage, timing of ecdysone signaling determines developmental progression, which could act as an environment dependent gateway. Intriguingly, this may suggest that, from the phylotypic stage onward, insect embryos can start to integrate internal and environmental stimuli to actively regulate important developmental processes. As we found evidence that there is genetic variation for temperature sensitivity of egg development rate in our study population, such regulation could be a target of selection imposed by climate change. Show less
Gamelon, M.; Vriend, S.; Visser, M.E.; Hallmann, C.A.; Lommen, S.T.E.; Jongejans, E. 2021
Various types of demographic data can be collected in the field: population censuses, capture–mark–recapture data, and so on. These data sources share common demographic information about the... Show moreVarious types of demographic data can be collected in the field: population censuses, capture–mark–recapture data, and so on. These data sources share common demographic information about the studied population. Bayesian integrated population models (IPM) make efficient use of these different types of demographic data by jointly analysing them. This chapter discusses the advantages and the possibilities offered by this integrated approach. It describes the different steps required to build an IPM and illustrates the usefulness of this approach using two case studies. The first case study is a short-lived bird species, the blue tit, taking advantage of different data sources collected in a Dutch population to highlight how an integrated analysis might help to obtain a comprehensive picture of its dynamics. This IPM also assesses whether and how beech crop size might influence vital rates. The second case study is an invasive plant species, the common ragweed. The chapter illustrates how seedling data, plant data, and seed bank data could be analysed simultaneously to estimate key vital rates such as the probability that a seedling survives up to flowering. Show less
Harvey, J.A.; Heinen, R.; Armbrecht, I.; Basset, Y,; Baxter-Gilbert, J.H.; Bezemer, T.M.; ... ; Kroon, H. de 2020