Diapause is usually done by
insects. It is a ‘sleep
time’ that is different from hibernation
because the animals do not grow during this time.
There are two kinds of diapause:
 |
Obligatory--a word
that just means that the animal or insect MUST do this at some
stage in its development. It has no choice. |
|
Facultative--another
big word that means the animal goes to 'sleep' because something
bad is going to happen. This is different from
other kinds of hibernation
that happen AFTER something bad happens. With
facultative diapause, the creature goes to sleep BEFORE
the drought or cold weather. |
Diapause is the way animals adapt
to the world around them. It
happens a lot in places where food or water are only there for a little
while or the amount of food or
water changes. It is a way
for animals to live through droughts
or lack of food.
Insects
that stop growing have more of a chance to live if they can ‘sleep’
through the bad times and wake when things get better.
The animals or insects might:
|
Be active in the
spring and ‘sleep’ (be dormant)
in the winter [temperate
regions]. |
|
Be active in the rainy
season and ‘sleep’ during drought [tropical
areas]. |
The insects get warning signals a few times before they actually
do anything about it. These
warning signs might be:
|
Days becoming shorter.
Animals can sense this and send out the message for ‘sleep’. |
|
Outside temperature
going lower than usual. |
|
The quality or
quantity of food goes down. |
Long-day insects are the ones that go into diapause because the days get
shorter. Short-day insects
go into diapause when there are longer days.
This is part of the genes in an animal.
After a few warning-signal days, the female
will lay ‘diapausing’ eggs. These
eggs will have their cycle from egg to adult stopped somewhere.
Some examples of these ‘sleepers’ are:
Animals would become extinct without adapting to their habitats.
