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Hippo's Sunscreen Formula | Bioinspired Design Insights |


Did you know that the sweat of a hippopotamus, despite being colorless at first, magically turns red and then brown within a few minutes of being exposed to air? Researchers have been investigating this fascinating phenomenon and have made some remarkable discoveries.

Though it's not exactly sweat like we humans have, this liquid plays a similar role for hippos, helping them control their body temperature and might even have some antiseptic properties. Imagine collecting this red secretion by carefully wiping a hippopotamus's face and back with gauze. It's like capturing a magical color-changing potion!

The researchers worked hard to understand the secret behind these color changes. They managed to isolate and study the pigments responsible for the transformation. What's more, these pigments turned out to be quite special. They are non-benzenoid aromatic compounds, which means they have unique structures that make them behave in unusual ways. Surprisingly, they are also acidic and have some exciting properties.

Further Reading

Saikawa, Y., Hashimoto, K., Nakata, M. et al. The red sweat of the hippopotamus. Nature 429, 363 (2004).