Day 22: golden crown

•

Metamorphosis Watch: Day 22  

Many different butterfly chrysalises develop golden markings. The word chrysalis itself comes from the Greek word: chrysos, meaning "gold." 

As to why they do it is a mystery. Perhaps the jewels help to make the pupa look non-living, non-edible with the reflecting glitter serving as a royal camouflage. How it does it is easier to determine. The raised beads are created by their structure, layers of chitin filled with fluid that act like mini prisms to reflect the color yellow-gold. But again, we are back to "why."

At this point in any natural history question the answer has to be, "because it works. 200 million years of evolution has rewarded the processes that are successful." 

Similarly to the jewels, an indigo bunting's feathers are internally structured to reflect a dark blue sheen. Otherwise, it would be another black bird. 

At Day 22, the kids in the back seat are asking, "are we there yet?"

Stay tuned.


•