Concept 14 Mendelian genetics cannot fully explain human health and behavior.

factoid Did you know ?

One of the traits listed by the Eugenic Records Office is "pauperism," the tendency to be poor.


How much of a person is determined from their genetic makeup?

I'm Charles Davenport. I was the director of the Station for Experimental Evolution at Cold Spring Harbor, and I established the Eugenics Record Office (ERO) in 1910. At the ERO, we trained field workers in the collection of data to track human genes. We thought that all human traits, even behavior, were defined by Mendelian inheritance of genes. World War I showed us that a great modern war required drafting thousands of nonmilitary men to take on the rank of naval officer. I offered my 1919 monograph, Naval Officers: Their Heredity and Development as "an improved method of testing the fitness of untried officers." Naturally, I included Admiral David Farragut among my survey of the traits and pedigrees of 68 famous naval officers. Who isn't familiar with his famous 1864 adage: "Damn the torpedoes! Full speed ahead." He said this while roped to the mast of his flagship, the Hartford. Farragut directed a course straight though an extensive mine field blocking the Union fleet's approach into Mobile Bay. I concluded that, like other officers who were "fighters," Farragut's "combative gift" arose from a nervous hyperactivity. His juvenile promise showed up as a love of the sea and adventure. Let me show you his pedigree and tell you about a few of his close relatives. Farragut is highlighted – the filled square is the symbol for a high-ranking naval officer. Notice his father and brother were junior officers, indicated by half-filled squares. Notice also a familial trait for fearlessness. (Marked by a dot.) Father George was master of a gunboat on the Mississippi River during the early 19th century, serving in the war of 1812 and with Gen. Andrew Jackson in the Indian wars in Florida. His "most daring enterprise" was sailing a canoe from New Orleans to Havana. Farragut's mother, Elizabeth, once single-handedly fended off a raiding party of Indians with an axe. Brother William was a junior officer in the navy, and joined David in a cruise against the pirates of the West Indies. Brother George's naval potential was cut short, when he fell off a boat and drowned at age 10. As a teenager, Farragut's only son, Loyall, joined him on his campaign in Florida during the Civil War. He showed the family trait of fearlessness when he insisted on staying on deck as the Hartford passed heavy fire from the Confederate batteries at Port Hudson. From my study, I concluded that thalassophilia, "the love of the sea," is a key trait shared by naval officers. Since it showed itself exclusively in men, I concluded thalassophilia was an X-linked recessive trait. I suppose this sex bias could also be explained by the fact that, in my time, women were only allowed on ships as passengers. [Officers of the U.S.S. Monitor, 1862. Courtesy of the Library of Congress.] I suppose it is also possible that many men in my study might have loved the sea because they grew up around boats and sea-faring men. Farragut himself probably benefitted from being adopted as a child by Naval Commander David Porter.