The Red Squirrels fur is soft,
like very, very soft.
The closest resemble is kitten fur,
or chinchilla fur.
The tail is a little bit more coarse,
or more stiff than the rest of the fur,
giving it that distinctively big
and fluffy look.
The red squirrels fur
changes with the seasons.
As it gets colder,
the fur will start to get more grey,
eventually turning pure white.
This highly depends on
where they are located in the world,
in these photos,
it's the rough Siberian winter
in Russia.
In Denmark, Sweden,
Norway and on,
the fur changes won't be as extreme
as in the far north of the globe.
As the winter gets colder,
their ear tufts, or ear hair gets longer
and thicker, to isolate the heat better.
Squirrels regulates
their body temperature,
through the blood vessels
in their ears.
As spring starts to appear,
they will regain their lush,
brownish and red color,
to better camouflage themselves
on the forest floor.
Resembling a fallen leaf.
As the temperature rises,
the red squirrel will loose
their cute ear tufts,
to better disperse the heat and again,
to regulate their body temperatures.
So why doesn't Tintin's fur change?
As he primarily lives indoors,
his climate is barely changing
over the seasons, causing him to
have a constant state of spring fur.
He might get a little grey
behind his front legs doing winter,
but that's all that's going to change.