Though farmers had known for centuries that crossbreeding of animals and plants could favor certain desirable traits, Gregor Mendel's pea plant experiments conducted between 1856 and 1863 established many of the rules of heredity, now referred to as the laws of Mendelian inheritance.
Their joint essay was the runner-up in the 1968 Gravity Research Foundation competition. Hawking said he and Penrose split the $300 prize.
The San Andreas Fault is a continental transform fault, meaning the plates slide past each other along a fault line. It extends roughly 800 miles (1,300 km) through California and forms the tectonic boundary between the Pacific Plate and the North American Plate.