Some animals' fur grows thicker for staying warm in the winter.
Mammals are also warm-blooded and are covered with hair or fur.
Some animals are warm-blooded for staying warm in the winter.
some animals are what for staying warm in the winter?

a) hot headed
b) dormant
c) coiled
d) warm-blooded
e) cold-blooded
f) When it's cold
g) chill minded
h) bullfrogs