A changing climate has the potential to greatly impact ectotherms, which depend on the environment to regulate their own body temperatures. In a new study published in the American Journal of Physiology- Regulatory, Integrative and Comparative Physiology, researchers were curious how exposure to varying temperatures would affect developing ectotherms. They answered this question using Drosophila melanogaster, commonly known as fruit flies. They exposed freshly laid eggs to ten different temperatures ranging from 12 to 32°C, the upper and lower limit of survival for these insects. They found that adult female fruit flies tolerated heat better than males. In addition, male flies developed slower than female flies. Although cold tolerance was the same for both males and females. Interestingly, developing flies exposed to cold temperatures were less tolerant of cold exposure as adults. Moreover, animals exposed to either extreme did not live as long as animals exposed to more moderate temperatures during development. By measuring changes in metabolites with each temperature, they were able to identify several target molecules that may play important roles in helping the animals adapt to varying environmental temperatures. Although additional experiments may be necessary to determine if the specific molecules they identified are directly related to helping the animals acclimate.