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:
“Good resolutions are useless attempts to interfere with scientific laws. Their origin is pure vanity. Their result is absolutely nil. They give us, now and then, some of those luxurious sterile emotions that have a certain charm for the weak.... They are simply cheques that men draw on a bank where they have no account.”
—Oscar Wilde (1854–1900)
“The essence of morality is a questioning about morality; and the decisive move of human life is to use ceaselessly all light to look for the origin of the opposition between good and evil.”
—Georges Bataille (1897–1962)
“The real, then, is that which, sooner or later, information and reasoning would finally result in, and which is therefore independent of the vagaries of me and you. Thus, the very origin of the conception of reality shows that this conception essentially involves the notion of a COMMUNITY, without definite limits, and capable of a definite increase of knowledge.”
—Charles Sanders Peirce (1839–1914)