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
Famous quotes containing the word history:
“History, as an entirety, could only exist in the eyes of an observer outside it and outside the world. History only exists, in the final analysis, for God.”
—Albert Camus (1913–1960)
“We aspire to be something more than stupid and timid chattels, pretending to read history and our Bibles, but desecrating every house and every day we breathe in.”
—Henry David Thoreau (1817–1862)
“The history of mankind interests us only as it exhibits a steady gain of truth and right, in the incessant conflict which it records between the material and the moral nature.”
—Ralph Waldo Emerson (1803–1882)