Abstract
Many organisms reproduce earlier in warmer springs but, although it appears so at first glance, this phenotypic plasticity is not sufficient to cope with increased temperatures due to global climate change. Plants, insects and vertebrates respond differently to the increased temperature so organisms become mistimed to their food supply. This leads to selection on the way animals vary their timing in relation to environmental conditions (their phenotypic plasticity), as we have convincingly shown in the great tit. This makes studies of selection on, and heritability of, phenotypic plasticity both timely and important. Currently, we are in a unique position to do this, as a result of applying quantitative genetics methodology recently developed for use on wild populations to our globally unique long-term data on wild great tits. We therefore have an unparalleled opportunity to link phenotypic plasticity to the underlying physiological mechanism (and its genetic determination), and, from this, predict the response to selection, which is crucial in this changing world. We will, for the first time, assess genetic variation in the physiological mechanism underlying the phenotypic plasticity using our world-ranking facility of 36 climatized aviaries where we can breed great tits with a known genetic background under controlled conditions. Furthermore, we will link the quantitative genetics of the reaction norm with molecular genetics, identifying the genes that underlay phenotypic plasticity. This new integrative research will enable us to make predictions about the rate of adaptation of plasticity under the various climate scenarios of the Intergovernmental Panel on Climate Change (IPCC) and compare these rates of adaptation with the predicted rates of change in the environment. From this, we will calculate the maximal rate of environmental change that species can cope with. More severe climatic change will have major effects on the viability of populations, and thereby on biodiversity.
Netherlands