UC Berkeley

Circadian (from the Latin, circa-about; diem-day) rhythms temporally coordinate neural and hormonal systems on a daily schedule to maintain optimal health and functioning. In adults, disruptions to circadian functioning through poor sleep hygiene, night or rotating shift work, transmeridian travel and exposure to artificial light at night are associated with a number of disease states, including obesity and metabolic disease, diabetes, heart disease, cancer, deficits in cognitive functioning and reproductive dysfunction, among other maladies. However, whether circadian disruption negatively impacts typical development, leading to permanent deficits in brain physiology and behavior, has been minimally explored outside of early life disruption. In addition, most studies to date focus on male animal models whereas the present studies explore whether or not chronic circadian disruption (CCD) differentially impacts both sexes. The present studies identify adolescence as a period in which CCD has differential impact on brain and behavior depending on the sex of the organism. These findings further underscore the need for inclusion of both sexes in studies of CCD and to consider of the age at which disruption occurs.

In this thesis I also apply the concepts of just science and good science to teaching undergraduate biology students about biological sex. Broadly, just science establishes that science is created in an objective vacuum outside of most social influences, and that implications of science arise from the interactions with society after the fact. An important caveat of why the concept of good science is a promising prospect to explore in students from the biological sciences is that it is carefully crafted to not be anti-science. Some students reported how they had initially thought biological sex was unchangeable or always addressed in biomedical research but, given the new information from scientists and feminists scholars, they had changed their view. Others remained adamant that biological sex cannot be changed regardless of a person’s identity. Thus, my findings suggest further exploration on bringing good science around biological sex to earlier stages of students’ college education, as opposed to be hidden in specialized and advanced courses. In summary this thesis explores the impact of addressing diversity and complexity both in biology research and instruction to not over simplify or look over the destructive biases that have been identified.