Human canalization and female growth buffering with Drosophila as a model organism
Child health is a central concern in populations experiencing economic, environmental, and nutritional stress. Adversity, however, does not affect individuals uniformly as preferential child investment and underlying biological processes may lead to instances of differential growth outcomes among boys and girls. The causes of such differences may be misinterpreted when examining health and nutrition survey data and are deserving of inspection. This research utilizes an evolutionary female canalization model to broadly contextualize observed instances of sex-specific growth outcomes. The objectives of this research are to: (1) investigate sex-specific differences in growth and development; (2) address contributing cultural factors of the target population; (3) create a biological framework for understanding female canalization; and (4) create a robust understanding of sex-specific growth outcomes that can be used to interpret health and nutrition survey data. To complete these objectives, this research uses the Cebu Longitudinal Health and Nutrition Survey of the Philippines as a database for analysis. Drosophila melanogaster was employed as a model organism to investigate female canalization as an ancestral biological and evolutionary mechanism present in both Drosophila and humans. Human results indicate that girls are less sensitive to adverse environmental conditions and show more stable patterns of growth and development than boys. Drosophila results suggest there to be significant sex, diet, and genotype interactions that contribute to differential male and female phenotypic outcomes. These results show there are shared, sex-specific developmental characteristics between humans and Drosophila and that an understanding of contributing factors is crucial to future interpretations of health and nutrition survey data.