Bits of Books - Books by Title
She has Her Mother's Laugh
The Powers, Percersions, and Potential of Heredity
Carl Zimmer
More books on Evo and Heredity
More books on Food
In Middle Ages, membership of noble families became more widespread, making it more impt to keep track of who really was noble. So family histories began to be written down, first as vertical lines, but then as trees, with the founder at the base. French called these pics pe de grue, meaning 'crane's foot', bc that was what it resembled. From this we get the English word pedigree.
Potatoes are almost always grown by cutting up a tuber and planting the bits, so always a clone. Over thousands of years of breeding, domestic potatoes almost completely lost ability to reproduce sexually, by growing flowers and pollinating seeds.
Luther Burbank in Massachusetts read Charles Darwin's The Variation of Animals and Plants, which told him that variations came from cross-breeding, and that breeders cd produce new varieties. So when he came across a seed ball in his potato plot, he recognized its possibilities. From that single seed ball he grew a whole lot of potatoes of different shapes, colrs and sizes. One turned out to be smooth, large and white, and also stored well through the winter. Burbank was able to sell the potato to a seed merchant for $150 in 1875. The merchant named the variety after Burbank. A descendanr, the Russet Burbank, carpets much of Idaho. It's the only potato that McDonalds uses for its fries.
Burbank moved to California where he finally made real money. A grower wanted 20,000 plum trees in a hurry, which no-one cd do. Burbank grew almond seedlings, then grafted plum buds onto them. When the plums grew big enough, he pruned off the almond branches, and delivered the plum trees on time.
He plowed all the profits back into constant experimentation, producing new varieties of flowers, fruits, nuts and vegetables that were better tasting or hardier. Although he had no educational qualifications, he was recognized by scientists bc he was demonstrating principles of heredity that you cd see and taste.
With each generation, ancestral DNA gets cut up randomly into smaller and smaller bits. If you brought together 100 of your third cousins, one of them wd have no shared DNA with you. If it were 100 fourth cousins, 25 of them wd have no shared DNA.
If you go back far enough in history of a human population, you come to a point where all the individuals whio have any living descendants, are the ancestors of all living people (p189).
In 1960's noticed that blacks in US had much higher blood pressure than whites, and consequently had high early mortality rate from heart attacks. Assumed that it was a genetic flaw in negro race. But when went to Africa and tested blacks in Nigeria and Cameroon, found that they had substantially lower BP, and in fact lower than whites in US. But the crucial factors environmental - blacks living in high crime neighbourhoods with less access to good food and health care.
For some reason the best source of DNA from old bones comes from hard bony case surrounding the inner ear. Can get DNA from there even if none in rest of skeleton.
The people of Madagascar have half their genes coming from East Africans, and half from Southeast Asia, likely from people outsailing in Indian Ocean and getting blown right across. A 2006 study traced the ancestry back to a single village in Borneo.
Books by Title
Books by Author
Books by Topic
Bits of Books To Impress
|