Biology 11th Edition by Gerald Audesirk,Teresa Audesirk,Bruce Byers

Exercise 5

Only a few hundred of the more than 200,000 species of plants have been domesticated for human use. One example is the almond. The domestic almond is nutritious and harmless, but its wild precursor can cause cyanide poisoning. The oak makes potentially nutritious seeds (acorns) that contain very bitter-tasting tannins. If we could breed the tannin out of acorns, they might become a delicacy. Why do you suppose we have failed to domesticate oaks?