Diapause – What is it and what animals do it?

diapause

Some beetles enter a state of diapause during winter. Photo via Flickr.

Do you feel like going into diapause this winter?  That may not be possible for humans, but what animals use that winter survival strategy and what do you know about it?

Animals have a lot of different winter survival strategies, especially in the Rocky Mountains.  One that you may have heard about, diapause, is used mainly by insects to get through the cold winters.  Here is a little bit of information about this amazing process that allows bugs to suspend development for a short time.

What Is Diapause?

It is a form of dormancy when a animal, most usually bugs, take a break from developing due to bad external conditions (such as freezing cold).In other words, it is as if the animal simply takes a break until the conditions outside are more favorable.

During this period in an animals life there is no growth, development, or movement happening because the animals has stopped that temporarily.  It is as if the animal has stopped actively living because the conditions are too harsh and it is waiting until the conditions for living are better.

In the Rocky Mountains, many insects go into this during the freezing, cold winter months to survive until winter.  In other words, they overwinter in their larval or pupal form in a state of diapause.

diapause, yellow jacket, wasp

Some wasps, like this yellow jacket enter diapause.

What Animals Go Into Diapause?

The main kind of animal that goes into diapause are insects or bugs, including beetles and wasps.

Most often diapause does not occur in the adult form of the animal, but is done in the pupal form.  In some animals diapause can occur in the embryo to slow down the development and birth of a baby until conditions are better.  Animals that can do this include lungfish, and chickens.

What Happens To Bugs When They Are In Diapause?

During this stage in a bugs life their metabolism, heart rate, and temperature all drop quite low and they are inactive.

diapause

Car engines have anti-freeze to keep them from freezing in winter. Some bugs have an anti-freeze like this. Photo via Flickr.

Bugs are able to become very cold without freezing and damaging the cells in their bodies.  This is possible because they replace the water in their bodies with glycerol, something that does not freeze as easily. This is like putting an anti-freeze in their body, which is the same thing we put in our car engines to keep them from freezing.