Origins of Life On Earth
Further information: Evidence of common descent, Common descent, and Homology (biology)Biologists reason that all living organisms on Earth must share a single last universal ancestor, because it would be virtually impossible that two or more separate lineages could have independently developed the many complex biochemical mechanisms common to all living organisms. As previously mentioned the earliest organisms for which fossil evidence is available are bacteria, cells far too complex to have arisen directly from non-living materials. The lack of fossil or geochemical evidence for earlier organisms has left plenty of scope for hypotheses, which fall into two main groups: 1) that life arose spontaneously on Earth or 2) that it was "seeded" from elsewhere in the Universe.
Read more about this topic: Evolutionary History Of Life
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“The origins of clothing are not practical. They are mystical and erotic. The primitive man in the wolf-pelt was not keeping dry; he was saying: “Look what I killed. Aren’t I the best?””
—Katharine Hamnett (b. 1948)
“Lucretius
Sings his great theory of natural origins and of wise conduct; Plato
smiling carves dreams, bright cells
Of incorruptible wax to hive the Greek honey.”
—Robinson Jeffers (1887–1962)
“For some men the power to destroy life becomes the equivalent to the female power to create life.”
—Myriam Miedzian, U.S. author. Boys Will Be Boys, ch. 4 (1991)
“A good businessman never makes a contract unless he’s sure he can carry it through, yet every fool on earth is perfectly willing to sign a marriage contract without considering whether he can live up to it or not.”
—Dalton Trumbo (1905–1976)