You‘d know if you were drowning, right?
This is Sandra Tsing Loh with the Loh Down on Science saying…
WRONG! The feeling of drowning isn’t from lack of oxygen… It’s from too much carbon dioxide. But not for gray seals! HAUH?
Enter J. Chris McKnight and team from the University of St. Andrews! They have an indoor pool for gray seals with a controlled air climate. When seals come up to breathe, they inhale varying levels of carbon dioxide and oxygen.
And? More oxygen means longer dives. But carbon dioxide? NO EFFECT!
Unlike us, seals are tuned to oxygen, not carbon dioxide. Which means….they come up for air RIGHT ON TIME.
No drowning seals here. Evolution’s got their back!
Reference: McKnight, J. C., Bønnelycke, E. M., Balfour, S., Milne, R., Moss, S. E. W., Armstrong, H. C., Downie, C., Hall, A. J., & Kershaw, J. L. (2025). Cognitive perception of circulating oxygen in seals is the reason they don’t drown. Science (New York, N.Y.), 387(6740), 1276–1280. https://doi.org/10.1126/science.adq4921