Example A -- HARE ANSWERS
The Affect of the Environment on Heredity
In rabbits, fur color varies in several
types of H A R E S such as the S N O W S H O E
H A R E of North America. In this species,
(1) in the W I N T E R, when the body temperature drops,
this species is pure W H I T E (Fig. 7)
(2) In warmer T E M P E R A T U R E S , the species is
pure B R O W N (Fig. 8)
The North American hare in Figure 9 shows both
some snow and
some grass in its
surroundings.
Is this hare in its Summer or Winter coloration? __ SUMMER __
(3) Even more striking is the study of the H I M A L A Y A N H
A R E from the mountains
of Asia.
Like its American cousin, they change color, but this time from White to Black
depending on the temperature
in different parts of their body.. Surprisingly, it is the Black
fur which grows in
on the coldest parts
of their body.
If a portion of the white back is
shaved & an ice pack is placed there, new B L A C K
fur grows at that location.
I regret that my image searches on both Yahoo and Google did not turn up any
photos
of this Asian
species in its winter coloration. Such is life. Here are a few other
Himalayan
Hare photos/sketches (10A,
10B, 10C, 10D) for
your inspection.
(4) In several species
of hares, the environmental variable that
controls the fur color gene is
T E M P E R A T U R
E
And the winner is choice
number one. This diagram shows that the production of the black fur
is due both to a gene for the production of the
black pigment and cold temperatures. Those areas
of the hare that maintain body heat stay white.