+ I* N+ l4 _% L7 N& }1 O6 |$ a( ICOVER A Classopollis meyeriana conifer pollen grain (~30 % _9 {5 a. s( c' c/ R6 Q" j& ~micrometers across) preserved in lake sediments deposited just after a massive, 5 d/ m9 A2 r5 j w9 Z f
volcano-induced extinction event ~200 million years ago. This fossilized pollen - _9 w; L P7 `! t Q5 Q
grain is representative of the low-diversity plant assemblages found within the ( Z9 U& r& m9 R" P' v
tropics of the Pangean supercontinent during the postextinction recovery period. - s% Q; g1 ]8 X0 t5 k0 kSee page 941. Image: " a! ?0 }, b1 w) M+ a; G
Dee Breger and Sarah Fowell/Science Source % m) B$ e/ j! K0 P; y* n 作者: 452359357 时间: 2013-5-24 13:25