Exceptions
There are notable exceptions to Haldane's rule, where the homogametic sex turns out to be inviable while the heterogametic sex is viable and fertile. This has been most commonly noted in Drosophila, where it is proposed to function through maternal effect genes and their interaction with species-specific heterochromatin.
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Famous quotes containing the word exceptions:
“Skepticism is unbelief in cause and effect. A man does not see, that, as he eats, so he thinks: as he deals, so he is, and so he appears; he does not see that his son is the son of his thoughts and of his actions; that fortunes are not exceptions but fruits; that relation and connection are not somewhere and sometimes, but everywhere and always; no miscellany, no exemption, no anomaly,—but method, and an even web; and what comes out, that was put in.”
—Ralph Waldo Emerson (1803–1882)
“For true poetry, complete poetry, consists in the harmony of contraries. Hence, it is time to say aloud—and it is here above all that exceptions prove the rule—that everything that exists in nature exists in art.”
—Victor Hugo (1802–1885)