Which came first the mammal or the flower? Well it looks like flowermay have ruled after the dinosaurs died out. So say researchers who have discovered the first fossil orchid, a 15 to 20-million-year-old pollen specimen encased in amber, in the Dominican Republic.
The Orchidaceae family boasts the largest of all flowering plants, but it is poorly understood, because until now there has been no fossil record of its history. Previous speculations put the plants' first appearance at about 45 million years ago.
Harvard University researchers and colleagues compared genetic information from the fossilised Meliorchis caribea with modern-day plants and reconstructed an evolutionary tree. It suggests that the first orchids bloomed about 84 million years ago.
Those that survived the mass extinction 65 million years ago then rapidly proliferated, leading to today's 25,000 or so species.
The Orchid family
Orchidaceae or the Orchid family is the largest and most diverse of the flowering plant (Angiospermae) families, with over 800 described genera and 25,000 species.
Orchids, like the grasses and the palms, which they resemble in some ways—for instance the form of their leaves—are monocotyledons. They have one cotyledon, or embryonic leaf, in contrast to the two of most flowering plants.
Orchids are world wide in distribution, occurring in every habitat, except Antarctica and deserts. The great majority are to be found in the tropics, mostly Asia, South America and Central America. They are found above the Arctic Circle, in southern Patagonia and even on Macquarie Island, close to Antarctica.