Dinosaurs ‘Round the Christmas Tree
December 17, 2012
Conifers, which are traditionally used as Christmas trees, have remained much the same since the Age of Dinosaurs, according to new research. Conifers, a major group of plants that produce their seeds in cones, include pines and firs as well as many other plants. The research showed that the genes of conifers have been remarkably stable for at least 100 million years. Genes are the basic units of heredity that guide the growth of living things.
By contrast, flowering plants have changed considerably. Flowering plants, which scientists call angiosperms, make up the vast majority of living plants, with hundreds of thousands of species. There are only about 600 species of conifers. By comparing the genes of conifers and angiosperms, the researchers showed that angiosperms have gone through major changes in the last 100 million years. Angiosperms first appeared around the middle of the Age of Dinosaurs, but they were already spreading rapidly into many new environments by the time the dinosaurs became extinct, about 65 million years ago. As angiosperms have diversified and adapted to new conditions, their genes have changed extensively. The Age of Dinosaurs is known scientifically as the Mesozoic Era. This period lasted from about 251 million to 65 million years ago.
The research suggests that even early conifers already possessed the adaptations that remain crucial to their success. An adaptation is a characteristic of an organism that makes it better able to survive and reproduce in its environment. Chief among these may be the ability of conifers to survive in areas with little available water. Conifers also thrive in colder regions, such as in the great boreal forests of northern Asia, Europe, and North America. However, conifers are not nearly as diverse as angiosperms, and they have not been able to compete in such regions as the tropics. The research was published in the journal BMC Biology.
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