Researchers
have long wondered what caused the Monarch Butterflies to migrate north after
winter and after some research they concluded the cold triggers the butterflies
to fly north. Every fall, millions of
Monarchs fly from their northern habitats south to central Mexico to escape the
wintery cold. In Mexico they huddle
together in roosts to fight off the cold.
This “snuggling” helps create a cozy microenvironment for the butterflies
that safeguards against high and low temperatures. This journey is hard work for the Monarchs,
as their vibrant orange and black colors are stripped and their wings become
tattered. However, they are strong
enough to be able to begin migrating back up north, find food, and reproduce,
leaving it to their offspring to continue their journey north. 
Up until
now, scientist suspected that environmental factors like temperature or
changing day lengths triggered the Monarch’s flight back. A team of scientists conducted an experiment
involving south-bound Monarchs captured in the U.S. They exposed them to cold temperatures and simulated
the daylight changes they would see in Mexico.
The results were identical as both lab-wintered groups flew north. After comparing data with a team of
researchers who captured Monarchs on Texas, they found that just 24 days of
cold temperature exposer was enough to trigger the butterflies’ change in
flight directions.
Themes of Nature of Science:
Collaborative: Multiple scientists worked together on this
study
Based on Evidence:
Scientists did multiple experiments to back their hypothesis up
Subject to Debate and Tentative: The scientists are hoping to do more research
to see just how much Monarchs can sense temperature changes
I have also wondered how they know when to leave and go south for the winter so i found this article very interesting. One thing I would be interested to find out is how the monarchs know which direction is north and south. I also found it interesting that they huddle together to stay warm!
ReplyDeleteThis is another article about monarchs migration
http://www.monarchlab.org/Lab/Research/Topics/Migration/WhenToLeave.aspx
I found this article rather interesting because I too have always wondered the same thing. I found it so cool and decided to learn more about it. I'm not sure if during the experiment, when the monarchs would change direction, if that was merely a coincidence because they didn't like the cold not because of the need to actually migrate. I did some more research on it. Here is an article explaining more in depth about the process of migration for monarchs.
ReplyDeletehttp://butterflywebsite.com/articles/uminn/monarchs.html
wow this is something that has "bugged me" for a while too (no pun intended). I have always been curious as to why monarchs are so smart and capable of making this journey and surviving. I did some further reading and found on this one website how monarchs are the only insect that travel over 2500 miles to escape the winter weather! wow thats just mind-blowing to me, and the thought that a new generation returns to where the parents used to be is incomprehensible to me. I can't quite understand how they know when and where to get back home, but it definitely has something to do with how they've evolved and adapted to being able to withstand such a strenuous journey!
ReplyDeletehttp://www.monarch-butterfly.com/monarch-migration.html