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QUICK-SETTING resin preserves the DNA of ancient plants and animals better
than resin that dries slowly, according to Scott Rogers of the State University
of New York in Syracuse. So the ability to recover DNA trapped in amber may
depend on whether or not the prehistoric Sun was shining. Rogers and his
colleagues added pieces of fungi to resin from Douglas fir trees. The
researchers found that the fungal DNA was well preserved in resin that dried
quickly in sunshine, but was severely damaged in slow-drying resin that was kept
in shade and immersed in water (Naturwissenschaften, vol 87, p 70). No
one knows how long preserved DNA keeps. 鈥淭here is not yet a firm date that has
been set for the longevity of DNA,鈥� says Rogers.