Palm trees have been around a long time! According to the fossil record, palms were growing alongside dinosaurs, as early as 80 million years ago, which makes them
among the earliest flowering plants. Most trees and flowers that we normally think of as plants originated well after this, after about 50 million years ago. By 60
million years ago, palms were growing in many parts of the world, including areas where they no longer occur, such as northern North America and northern Europe. We can
tell these places must have had a warmer climate back then, as very few palms today are able to survive persistent cold temperatures, such as occur outside the tropics or
at high elevations.
Palms vary greatly in size. The largest reach over 150 feet (45 m), whereas there are numerous dwarf species, such as the potato chip palm (Chamaedorea tuerckheimii)
which may grow only 12 inches (30cm) high. The smaller palm varieties are much favored by indoor decorators. Palms always add a welcome splash of green to an otherwise
dull decor, and most literature and websites concern palm cultivation.
Biodiversity of palms is highest in the tropics, notably tropical rainforests. Over 200 genera are recognized, including a wide range of forms. This gives rise to
some confusion, since a number of well-known plants such as traveller's palm (Ravenala madagascariensis), the sago palm (Cycas revoluta), and the palm lily
or ti palm (Cordyline spp.), are not true palms at all.
Palms generally reproduce by passive fertilization. Their reproduction relies on transfer of pollen by the wind. Insects or other animals are not actively involved in
pollination. (There may be exceptions to this.) On the other hand, it seems likely that palm fruits have co-evoloved with animals that aid in dispersal. Tasty fruits are
generally regarded as morsels to tempt animals that will eat the fruit and disperse the seed. Hence a number of palm species are important food sources to animals and humans.
Several are of significant economic importance. The most obvious example is the date palm (Phoenix dactylifera), whereas the oil palm (Elaeis guineensis) is
also important for food oil and also for cosmetics.
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