Diving Adaptations in Sea Nomads

The figure is entitled “Bajau versus Saluan” and is a boxplot graph. There are two points along the x-axis that are labelled with the southeast Asian populations: Bajau and Saluan. The y-axis is labeled Spleen Size in cubic centimeters and ranges from 0 to 350 in increments of 50.

Topic

Resource Type

Level

High School — General High School — AP/IB College

Saved By

23 Users

Description

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.

Estimated Time

Within one 50-minute class period.

Key Terms

adaptation, box-and-whisker plot, boxplot, diving reflex, diving response, hypoxia, oxygen, red blood cell, spleen, thyroid hormone

Primary Literature

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.