本帖最后由 细胞海洋 于 2013-4-15 08:15 编辑 $ V C! L% y. z% z4 X# E $ ~2 v; @* E3 w! _% G + `' ~7 D3 ^* @& j3 c : g) A4 L K+ r- M6 d2 LAbout the cover& [' h4 y1 @* u) d# T% u
: J/ R4 n- x4 y9 a. E, n$ n3 [Fossil dinosaur & n1 P) F! T6 T
embryos are extremely rare, and mainly restricted to the Late Cretaceous period. - S4 H5 Q' ]6 @0 Z0 N( LHence the interest in a newly uncovered bone bed of Lower Jurassic sauropodomorph # ^# K" f; l, _
embryos from China, which at about 190–197 million years old is the oldest - q, {% H8 a, ]4 l1 H/ xassemblage of such bones ever found. A three-year multinational programme of $ u3 y8 K7 w2 D" c. }( k# t1 B& Fexcavation and research has yielded a treasure trove of embryonic bones, and the + x& S4 T7 y% R7 a4 ~, u3 c+ C1 T' Moldest known evidence of organic remains. Study of bones preserved at various . W8 F- P' e* w8 R9 h) }6 kdevelopmental stages indicates that these large dinosaurs had a short incubation ; a5 N; B5 h3 Q% _9 ltime and flexed their muscles while still in the egg, preparing the growing 3 c* s3 [* K3 T/ b# D ?, E
skeleton for life in the outside world. On the cover, a coloured thin section of $ C2 f9 b# O- ~! p F
an embryonic femur showing its internal tissues and large marrow cavity. 4 z2 ^! E1 P5 a3 f* K% {$ C
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