Origin
In most sheep, a white fleece is not albinism but a dominant gene that actively switches color production off, thus obscuring any other color that may be present. As a result, a black fleece in most sheep is recessive, so if a white ram and a white ewe are each heterozygous for black, in about 25% of cases they will produce a black lamb. In fact in most white sheep breeds only a few white sheep are heterozygous for black, so black lambs are usually much rarer than this.
Read more about this topic: Black Sheep
Famous quotes containing the word origin:
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—Oscar Wilde (1854–1900)
“Our theism is the purification of the human mind. Man can paint, or make, or think nothing but man. He believes that the great material elements had their origin from his thought.”
—Ralph Waldo Emerson (1803–1882)
“Art is good when it springs from necessity. This kind of origin is the guarantee of its value; there is no other.”
—Neal Cassady (1926–1968)