STATES CHRONICLE – Nature is many things, and fascinating is definitely in the top adjectives you should use to describe it. So many interesting things take place in nature, from natural phenomena to species diversity, and even animal evolution. Few things can be as awe-inspiring as the first time you see a thunderstorm, when you learn of giraffes, or when you find out about the evolutionary mechanisms employed by certain species.
And these small natural miracles come in all shapes in sizes, from the elephants’ recreational pastime of getting drunk to the wonders of the monarch butterflies’ biannual migration. And speaking of this last one, scientists finally figured out how the tiny insects manage to fly for two thousand miles twice a year without getting lost.
In case you’re not familiar with this particular migration, every year monarch butterflies travel from Canada, through the United States, to the more pleasant temperatures of central Mexico every autumn, only to go back home to Canada the same way they came once spring begins.
Scientists have been fascinated by this migration for quite a while, unsure of how these tiny creatures could fly for four thousand miles every year without getting lost. Even though scientists knew that it had to do with the insects’ ability to tell the sun’s location in the sky and the time of day, they didn’t really know how it worked until they made a model of their internal guidance system.
The creatures can tell the direction they’re supposed to head towards using two pairs of organs – their eyes and their antennae. Their very large, complex eyes are used to determine the sun’s position in the sky, while their antennae host a very complex and efficient internal clock. This clock, like in most species, is based on the rhythmic expression of certain genes.
By using these two key features, the monarchs can flawlessly tell which direction southwest is, and they are always heading in that direction during the initial trip. When they are to return, their guidance system simply changes southwest to northeast, allowing the creatures to make the trip back to Canada.
But there’s one more thing of particular interest regarding the internal workings of these majestic creatures. In order to be as certain as possible that they won’t go off-course, the guidance system of the monarchs generates a ‘separation point’. This point changes multiple times during a day, and is known at all times by the creatures.
The really interesting part is that this separation point can never be crossed. Say a butterfly is carried a bit too much to the east by a particularly strong gust of wind. If the separation point is located immediately to the west, the butterfly will not be able to turn west. Instead, it will double back east, making a full circle until reaching the right direction once more.
Image source: Pixabay