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mechanisms other than spring temperature —such as photoperiod or winter conditions — and will thus fail to respond or respond in different ways to climate warming. For example, during warm springs, poor synchrony has been observed between oak (Quer- cus robur) bud burst and winter moth (Operophtera brumata) egg hatching ( Visser and Holleman 2001), resulting in a mismatch between the caterpillars and their food supply. The mismatch is the result of different phenologic mechanisms; oak bud burst responds to spring temperatures whereas winter moth egg hatching is affected by the incidence of winter freezes. However, even for species for which temperature or precipitation is closely associated with the timing of phenologic events, genetic or other constraints may limit species' ability to respond. In a review of cases ranging from marine plankton to birds, Visser and Both (2005) found that the major- ity of species shifted either too much or too little in the timing of phenologic events, such as emergence, migration, or laying dates, compared to the shift in timing of food abundance. We know little about the potential implications that shifts in phenology may have on life history charac- teristics influencing reproductive success. For exam- ple, Winkler et al. (2002) looked at the consequences of earlier egg- laying dates on clutch size in tree swal- lows. In birds, there is a strong negative relation- ship between laying date and clutch size, however mean clutch size for tree swallows has not increased with advanced laying dates. Examples such as these suggest that previously established relationships among abiotic factors and life history traits may not adequately capture the impacts of climate change on factors influencing population dynamics (Stens- eth and Mysterud 2002) and quantifying responses of traits for single species may not go far enough in terms of understanding community dynamics (Berg et al. 2010). Berg et al. (20 10) argue that the tradi- tional approach for forecasting change in ecological community structure (i.e., modeling based solely on climate - species range relationships) will fail to accu- rately predict species changes because it ignores the potential role for biotic interactions (Box 1 -1). Box 1 -1. Examples of mechanisms that may facilitate disruption of biotic interactions under climate change (drawn from studies reviewed in Berg et al. 2010). Prey - predator Differential impacts on reproductive rates of predators and prey could result in a temporal mismatch in abundance. Plant- pollinator Disruption in the correlation between flowering period and pollinator activity could result in a temporal mismatch. Plant- pathogen Dissimilarity in dispersal ability could result in a spatial mismatch beween a plant and pathogen. Plant- herbivore Higher development rate in insect herbivores could result in an increase in herbivory intensity. Host - parasitoid Dissimilarity in lethal temperatures could enhance survival in a parasitized host relative to the parasitoid. Plant - mycorrhizae Climate impacts could alter root growth and morphology, adversely affecting the plant - mycorrhizal association. Plant- herbivore - predator Disrupted correlations between environmental cues used by plant and herbivore could cause a temporal mismatch between abundance and food supply across trophic levels.