Adaptation
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The artic fox has made several adaptations
to cope with its environment. The artic fox lives
in an environment that can be very harsh at times. This forces the fox to
adapt to the cold weather in the best way it can. These adaptations appear to
be well developed. Animals can cope with cold in many different ways.
These include producing more heat, reducing the thermal
conductance, and lowering the temperature gradient between the
body and the outside temperature.
Food scarcity can drastically change how animals have to deal
with extremely cold temperatures. They have to adapt to cope in a way that they have
the lowest possible energy loss. To do this they can avoid any activities such
as reproduction and growth that would consume a lot of energy,
avoiding extra heat production, reducing the amount of movement,
and lowering the BMR (basal metabolic rate). The arctic fox does not appear to have any drastic
seasonal BMR changes (Prestrud 1989). The rate of heat loss in arctic foxes has also
been found to be seasonally constant. This is due to an increase
in fur insulation, as well as a decrease in skin temperature.
The decrease in skin temperature is thought to be caused by
vasoconstriction of arterioles (Prestrud 1989). This is similar to rabbits and animals with
larger ears do to regulate their temperature. Decreasing the blood flow
to the skin allows for better insulation. More blood is sent to the
pads of the feet because of the high amount of contact with snow
(Prestrud 1989).
The way the fox is insulated are considered as sufficient to
keep from having an increase in the production of body heat and
to maintain a steady deep body temperature (Prestrud 1989). Animals also will change their behaviors to
cope with the changing temperatures. The arctic fox has well developed behavioral
adaptations. One of the arctic foxes adaptations is to dig a hole in the snow
in extremely bad conditions as protection from the wind. It will also curl up
into a ball with it’s tail covering its head and paws when the
temperature is very low to reduce surface-volume ratio (Prestrud
1989).
It is not yet known if the arctic fox will increase or decrease
its movement when the weather gets cold, but one researcher
(Underwood 1971) did state that the foxes appear to have more
movement in the summer months than in the winter months
(Prestrud 1989). Another behavioral adaptation that the foxes
have developed is its remarkable ability to Morphological
adaptations also help assist the foxes in cold weather survival. Some morphological
adaptations of the arctic fox are its small ears, short muzzle,
short legs, and small rounded body (Prestrud 1989). Fat is another great way to stay insulated in
the cold, as exemplified by animals such as whales and dolphins.
Fat storage increases in the arctic fox during the winter months
compared to the summer months. The percentages in the winter and summer months are
quite different at 22% and 7%, respectively, and are considered
to be significant (Prestrud 1989). The foxes don’t hibernate but they do build up
an increased amount of fat to help cope with the extremely cold
weather.
Check out the habitat page to learn more about the artic fox!