Tapestry Press
Made for Each Other
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Tapestry Press
Made for Each Other
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Made for Each Other, a Symbiosis of Birds and Pines by Ronald M. Lanner. Oxford University Press. 160p. Symbiosis refers to a close relationship between two species. One kind of symbiosis, mutualism is an association in which both partners benefit. Dr. Lanner, a retired professor of forestry, in this fine little book summarizes current research on the mutualism of certain western pines and certain corvids, members of the crow family. Stone pines such as white bark pines, possess large, wingless seeds containing about 50% oil. Curiously, unlike most eastern pines the cones attach above branches making them easily visible, and the scales open only after the pine seeds have deteriorated. Isolated white bark pines are unable to disperse seeds to complete reproduction. Clark’s nutcrackers remove the cone scales exposing the pine seeds. They place about 30 seeds in a special pouch beneath their tongue and fly away to cache the seeds in the soil. Each hides thousands of seeds every year. Contrary to the teachings of the importance of instinct in animal behavior classes, experiments have demonstrated that these birds remember for up to six months where the seed caches are located. Remarkably the sites are often covered with snow when the rich seeds are retrieved and eaten in winter. Those seeds that are forgotten or escape detection germinate to produce new white bark pines. Often they occur in clumps. The extinct Dodo bird had a mutualistic relationship with the Tambalacoque tree. Without birds to plant it’s seeds the last old Tambalacoque trees are now approaching extinction. By 1990 90% of the white bark pines in Glacier National Park had died due primarily to an introduced disease, white pine blister rust. Can we protect enough white bark pines to protect the Clark’s nutcrackers?Review written November 2002 Back to Book Reviews
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