A Tale of Hairless Rabbits
Name: ____________________________________________________________ Hour: _____ Date:_______
Snowshoe hare rabbits have many adaptations to stay alive during the long cold winters. Many of these
hares have been discovered shivering in hollow holes without any hair on their bodies. These hairless rabbits
have been collected and are brought to the animal shelters where they are given nice hand knit body sweaters.
These hairless rabbits are believed to have a genetic disease only found in a small number of rabbits. In
order to be hairless, the rabbits must be homozygous recessive. They must have both recessive alleles. Rabbits
can be carriers of the disease, this means that they have hair but could have hairless offspring. Carriers are
heterozygous for the trait of hairlessness.
Keep your eyes open while outside because you just might be the one to stumble upon one of these poor
hairless rabbits. Please report any sightings to Mr. Jeffery at the STMA Middle School as he is doing a study
on these unique animals.
Directions:
Your job is to create a pedigree diagram using the clues given below. Use page 132 in your textbook for
examples of how to set up a pedigree. Your pedigree will help you to discover the mystery of these poor
helpless rabbits. Make sure your pedigree has four generations, a title and a key.
Clues:
1) Both male and female in generation One are carriers of the hairless trait.
2) In generation Two, there are eight rabbits born. Three females are homozygous recessive or hairless, and
two females are heterozygous.
There are also three males in generation two, one male in this generation is homozygous recessive, the other
two are homozygous dominant (or have hair and are not carriers).
3) One hairless female from generation two mated with a male that was heterozygous (a carrier). Of the four
offspring in generation three, two females were homozygous recessive and two males were heterozygous
(carriers).
4) A male rabbit from generation two that was homozygous dominant mated with a female rabbit that was
heterozygous. They had three baby rabbits and all were females. What will all of the females look like?
Draw these rabbits onto your pedigree table.
5) The two males from generation three also found females to mate with. One of the males mated with a
female rabbit that was also heterozygous. They had three baby boy rabbits one with each possible genotype.
The other male rabbit mated with a female that was homozygous and had hair. They had two female
offspring each representing the probabilities expressed in a punnett square equally. Draw these fourth
generation combinations.
6) How easy will it be to find a hairless rabbit? (WHY?)____________________________________________
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7) Hand in your completed pedigree.