The lily family ballooned to 4,500 species, then DNA shrank it to 610
For two centuries botanists used the lily family as a wastebasket for any showy monocot that fitted nowhere else. By 1981 it held roughly 300 genera and 4,500 species. Molecular studies then evicted most of them, leaving about 15 genera and 610 species, including lilies, tulips and fritillaries.
Michel Adanson described the family in 1763, and Antoine Laurent de Jussieu formally named it in 1789, defining it by six equal coloured parts, six stamens, a superior ovary and a three-chambered capsule. That broad recipe invited trouble. In 1845 John Lindley grudgingly admitted the group had become a catch-all, holding 133 genera and 1,200 species, and hoped some unifying character would eventually emerge. Cronquist's 1981 system went further, merging in the amaryllis family. Today writers add sensu lato or sensu stricto to signal which version they mean.
Members of the slimmed family are perennial herbs that usually grow from bulbs, sometimes rhizomes, with contractile roots that pull them deeper into the soil. Flowers carry six petal-like tepals in two rings of three, often striped or spotted, with nectar at their bases. Habitat shapes form. Shade dwellers tend toward broad, net-veined leaves, small flowers, rhizomes and berries spread by animals, while sun lovers have narrow parallel-veined leaves, bulbs, large conspicuous blooms and capsules whose seeds ride the wind.
Genomes vary enormously. Fritillaria assyriaca has one of the largest known in flowering plants, about 127 picograms, while Tricyrtis macropoda manages just over 4. Chemistry also sets the family apart from former members like the onions: its seeds lack the sulphur compounds responsible for that alliaceous smell, while fritillaries contain steroidal alkaloids and tulips an anthocyanin called tulipanin.
The family probably arose between 82 and 52 million years ago, in the Late Cretaceous or Early Paleogene. It is concentrated in temperate parts of the Northern Hemisphere, and insects pollinate its flowers. Deer browse lilies heavily in some regions. Lilies and tulips underpin a major trade in cut flowers and dry bulbs and appear often in paintings, though some species are poisonous to people and pets, and others have served as famine food.
Source: Liliaceae
