History
Orthologs of AgRP, ASIP, MCIR and MC4R have been found in mammalian, teleost fish and avian genomes. This suggests that the agouti-melanocortin system evolved by gene duplication from individual ligand and receptor genes in the last 500 million years.
Read more about this topic: Agouti-related Peptide
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“Anything in history or nature that can be described as changing steadily can be seen as heading toward catastrophe.”
—Susan Sontag (b. 1933)
“There is a constant in the average American imagination and taste, for which the past must be preserved and celebrated in full-scale authentic copy; a philosophy of immortality as duplication. It dominates the relation with the self, with the past, not infrequently with the present, always with History and, even, with the European tradition.”
—Umberto Eco (b. 1932)
“I saw the Arab map.
It resembled a mare shuffling on,
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nearing its tomb and the pitch of hell.”
—Adonis [Ali Ahmed Said] (b. 1930)