浙江天台盆地蛋化石与恐龙的绝灭

Cretaceous fossil eggs from the Tiantai basin of Zhejiang,with a discus sion on the extinction of dinosaurs

综合报道了浙江天台盆地产出的蛋化石,其中包括新建立的龟鳖化石蛋科(新科)Testudoolithidaefam.nov.和天台蛋属(新属)Tiantaioolithusgen.nov.,以及5个新种:Dendroolithusshuangtangensissp.nov.,Elongatoolithuschichengshanensissp.nov,Elongatoolithuslaijiaensissp.nov,Spheroolithusjincunensissp.nov,Tiantaioolithusjiangisp.nov。这批蛋化石以赤城山组出现的类型最为丰富,有长形蛋、树枝蛋、圆形蛋、龟鳖类化石蛋等;赖家组蛋化石数量少,仅见长形蛋和圆形蛋类,其时代均为晚白垩世。推测天台蛋化石消失的原因是由于气候变冷,受精卵不能正常孵化所致。孵化率降低,生殖链打断,可能是引起恐龙绝灭的原因之一。

The occurrence of fossil eggs in the Late Cretaceous of the Tiantai basin,Zhejiang,southeastern China,is reported.They include the new family Testudoolithidae fam.nov.,the new genus Tiantaioolithus gen.nov.and five new species,Dendroolithus shuangtangensis sp.nov.,Elongatoolithus chichengshanensis sp.nov.,Elongatoolithus laijiaensis sp.nov.,Spheroolithus jincunensis sp.nov.and Tiantaioolithus jiangi sp.nov.The eggs found in the Chichengshan Formation are the most varied,including Elongatoolithidae,Phaceloolithidae,Spheroolithidae and Testudoolithidae fam.nov.,while in the Laijia Formation fossil eggs are scarce and only Elongatoolithidae and Spheroolithidae are found.The fossil eggs are Late Cretaceous in age.It is inferred that the cause for the disappearance of the Tiantai eggs was due to the cooling of the cli-mate,which led to the failure of hatch the eggs normally.The lowering of the hatching rate and breakdown of the reproductive chain might be one the causes for the extinction of dinosaurs.