Why fish are better at breathing than you are - Dan Kwartler

TL;DR

Fish gills are incredibly efficient at extracting oxygen from water, allowing fish to breathe underwater, unlike humans.

Transcript

In 2019, Eliud Kipchoge finished a Vienna marathon in one hour, 59 minutes, and 40 seconds. This staggering time broke the two-hour barrier that most runners previously deemed impossible. However, some researchers weren't as surprised. Recent studies investigating if humans could maintain such a high pace for the length of a marathon had found that... Read More

Key Insights

• 🏃 Elite runners benefit from a high oxygen intake to maintain fast paces during marathons.
• 🐟 Fish gills have a complex structure with gill covers, filaments, capillaries, and gill lamellae for efficient oxygen extraction.
• 👻 Fish breathe more frequently and efficiently than humans, allowing them to extract oxygen from water even in low-oxygen environments.
• 🫁 Some fish species, like the Australian lungfish, have both gills and lungs to survive in changing habitats.
• 🐟 Fish gills can absorb roughly 75% of the oxygen passing through them, making them highly efficient.
• 🐡 Fish living in low-oxygen environments adapt by increasing gill ventilation and oxygenated blood circulation.
• 🚾 The vast majority of Earth's surface being covered by water provides ample room for fish to leverage their gills' oxygen extraction abilities.

Questions & Answers

Q: How does the process of fish breathing through their gills differ from human breathing?

Fish breathe underwater through gills, which have a complex structure involving gill covers, filaments, capillaries, and lamellae that efficiently extract oxygen from water. Humans, on the other hand, breathe through lungs to extract oxygen from the air.

Q: Why do fish need to breathe more frequently than humans?

Fish breathe more frequently due to their need for efficient gas exchange underwater. They need to extract oxygen from water by constantly pulling it over their gills, allowing them to maintain their oxygen levels.

Q: How do fish living in low-oxygen environments adapt to survive?

Fish living in low-oxygen environments increase gill ventilation and have hearts that pump high volumes of oxygenated blood throughout their bodies. Some species, like the Australian lungfish, have both gills and lungs to survive out of the water temporarily.

Q: What is the key difference in the efficiency of oxygen extraction between fish gills and human lungs?

Fish gills can absorb roughly 75% of the oxygen passing through them, which is twice the percentage of oxygen extracted from a breath of air by human lungs. This high efficiency allows fish to thrive in aquatic environments.

Summary & Key Takeaways

• Elite runners like Eliud Kipchoge benefit from a high oxygen intake, a superhuman ability that helps them maintain a fast pace during marathons.

• Fish breathe through gills, using a process involving gill covers, filaments, capillaries, and gill lamellae to efficiently extract oxygen from water.

• Fish breathe more frequently and efficiently than humans, allowing them to extract oxygen even in low-oxygen environments.