Hippos secrete a thick fluid often nicknamed "blood sweat." What is it actually?

The answer

The red goo isn't blood. In 2004, chemists isolated hipposudoric acid and norhipposudoric acid from the secretion: pigments that start clear, turn red/orange, absorb UV, and inhibit bacteria. Built-in sunscreen and ointment for a mostly hairless giant.

Correct answer: A red, oily secretion that acts as sunscreen and antibiotic