Diving Adaptations in Sea Nomads
This activity guides the analysis of a published scientific figure from a study that investigated physiological and genetic adaptations in the Bajau, a group of people who traditionally do freediving.
For over 1,000 years, the Bajau have traditionally gathered food and other resources through freediving, diving that requires holding your breath underwater. They are known to dive as deep as 230 feet without an oxygen tank. In this study, scientists investigated whether the Bajau’s freediving abilities are due partly to selection for certain adaptations. The study focused on the spleen, which contracts to release oxygenated red blood cells in diving mammals. The figure compares the spleen sizes in the Bajau population and a nearby population, the Saluan, who do not traditionally do freediving.
The “Educator Materials” document includes a captioned figure, background information, graph interpretation, and discussion questions. The “Student Handout” includes a captioned figure and background information.
Student Learning Targets
- Analyze and interpret data from a scientific figure.
- Describe how natural selection may affect human populations in certain environments.
adaptation, box-and-whisker plot, boxplot, diving reflex, diving response, hypoxia, oxygen, red blood cell, spleen, thyroid hormone
Ilardo, Melissa A., Ida Moltke, Thorfinn S. Korneliussen, Jade Cheng, Aaron J. Stern, Fernando Racimo, Peter De Barros Damgaard, et al. “Physiological and Genetic Adaptations to Diving in Sea Nomads.” Cell 173, 3 (2018): 569–580. https://doi.org/10.1016/j.cell.2018.03.054.
Accessibility Level (WCAG compliance)
HS-LS1-3, HS-LS4-4; SEP2, SEP4, SEP5
AP Biology (2019)
EVO-1.G; SP1, SP4
IB Biology (2016)
AP Environmental Science (2020)
Topic(s): 2.6, 2.7
Learning Objectives & Practices: ERT-2.H, SP5
Common Core (2010)
Math.S-ID.3, Math.S-IC.1; MP2, MP5
Vision and Change (2009)
CC1; DP2, DP3