The next time that you’re in your local natural history museum, don’t just look at the large animals in the dioramas — really look for those hidden small animals, too: a brown-headed cowbird near a bison, a Botta’s pocket gopher peeking from a burrow, or a Blue Echo Butterfly on a flower. These smaller details in scenes get as much attention from museum staff as the central figures.
Turtle tears are not the only source of such salts for butterflies; the insects also readily get the salt from animal urine, muddy river banks, puddles, sweaty clothes and sweating people, said Geoff Gallice, a graduate student of entomology at the Florida Museum of Natural History, who has witnessed butterflies flocking to turtle tears in the western Amazon rain forest.
This region is lower in sodium than many places on Earth, because it is more than 1,000 miles (1,600 kilometers) from the Atlantic Ocean, a prime source of salt, and is cut off from windblown mineral particles to the west by the Andes Mountains. Dust and minerals make their way into the Amazon from the east, sometimes all the way from north Africa. But much of this material is removed from the air by rain before it reaches the western Amazon, Torres said.
The Blue Morpho Butterfly is a beautiful brown — yes, brown — butterfly. The microscopic scales on this rainforest butterfly manipulate light, reflecting back an intense blue light that makes them appear blue.
Professor Brian Cox explains how Monarch Butterflies navigate by “monitoring the position of the sun, and compensating for its location in the sky using their internal timekeeping mechanism… even when it’s cloudy.” This is an episode 5 preview of the BBC’s Wonders of Life. Full screen this.