Earlier today, we looked at why leaves change color–or, more specifically, why some trees change to red and some to yellow. Now, we turn our attention to the skies.
So, birds fly south for the Winter. But how do they pull off a trip like that, while you and I (or, maybe, just I) have no idea which way is north outside our hometowns? Actually, nobody knows for certain. But Matt Soniak at mental_floss has summarized three of the theories. My favorite:
A particularly cool study showed that migratory birds also use "celestial navigation" to find their way around in the dark. Captive birds placed in a planetarium changed their directional orientation when the star pattern on the ceiling shifted and became confused when the images of stars were dimmed. The scientists conducting the experiment suggest that birds use the layout of constellations in the sky as a compass.
I just like to imagine the phone calls between the bird guys, and the owner of the planetarium, both before and after the experiment.
Image courtesy Flickr user Corey Leopold, via CC
