Several genetic studies have concluded nectarines are produced due to a recessive allele, whereas a fuzzy peach skin is dominant. Nectarines have arisen many times from peach trees, often as bud sports. As with peaches, nectarines can be white or yellow, and clingstone or freestone. On average, nectarines are slightly smaller and sweeter than peaches, but with much overlap. The lack of skin fuzz can make nectarine skins appear more reddish than those of peaches, contributing to the fruit's plum-like appearance. The lack of down on nectarines' skin also means their skin is more easily bruised than peaches. The history of the nectarine is unclear; the first recorded mention in English is from 1616, but they had probably been grown much earlier within the native range of the peach in central and eastern Asia. Although one source states that nectarines were introduced into the United States by David Fairchild of the Department of Agriculture in 1906, a number of colonial-era newspaper articles make reference to nectarines being grown in the United States prior to the Revolutionary War. 28 March 1768 edition of the "New York Gazette" (p. 3), for example, mentions a farm in Jamaica, Long Island, New York, where nectarines were grown. Peacherine is claimed to be a cross between a peach and a nectarine, and are marketed in Australia and New Zealand. The fruit is intermediate in appearance between a peach and a nectarine, large and brightly colored like a red peach. The flesh of the fruit is usually yellow, but white varieties also exist. The Koanga Institute lists varieties that ripen in the Southern Hemisphere in February and March. In 1909, "Pacific Monthly" mentioned peacherines in a news bulletin for California. Louise Pound, in 1920, claimed the term peacherine is an example of language stunt. Flat peaches or "pan-tao" have a flattened shape in contrast to ordinary rounded peaches. In 2017, world production of peaches was 24.7 million tonnes, led by China with 58% of the total. Spain and Italy each produced more than one million tonnes. Raw peach flesh is 89% water, 10% carbohydrates, 1% protein, and contains negligible fat. A medium raw peach, weighing , supplies 39 calories, and contains small amounts of essential nutrients, but none is a significant proportion of the Daily Value (DV, right table). A raw nectarine has similar low content of nutrients.