To better understand how climate change will disturb today’s distribution of plants and animals, we can use interspecific studies along with a phylogeny to look at how different thermal preferences and physiological traits have evolved over time. Here we present preliminary findings from 12 species of native New Zealand stick insects (Phasmatodea) that have radiated from tropical ancestors and now span the full latitudinal range of NZ, from the warm, northern subtropics to the cool, southern temperate environments. We find that species from the subtropics have narrower thermal performance curves (TPCs) for feeding rate than species that occur in colder, southern NZ that are freeze tolerant. Using an acclimation treatment, we do not find that many species shift their thermal optimum suggesting that these species do not rely on plasticity to tune to their environment and instead broadened their thermal performance curves when colonizing temperate New Zealand. To further our understanding about the transcriptomic regulation of thermal performance in stick insects, we also present an RNA-seq experiment looking at differential expression in relation to heat stress in one temperature sensitive species Clitarchus hookeri that occurs throughout New Zealand. In addition, we propose an experiment using whole genome bisulfite sequencing to examine how DNA methylation and microRNAs (miRNA) change in relation to temperature stress and determine the extent to which thermal performance is controlled by epigenetic mechanisms.