Evolutional size change in living and fossil Gephyrocapsa

我们研究了西北大西洋第四纪的GePhyrocapsa化石的形态和形态计量学变化，培养品系球虫的形态计量学变化与生长期的关系，以及活的大洋参在核、叶绿体和有丝分裂序列上的遗传变异。化石的形态研究表明，小盾壳化石的中心区形态、远端屏蔽体形态和桥角形态各不相同。培养实验表明，不同菌株在静止期产生的球虫比对数期产生的球虫大，且球虫的大小范围不同。分子生物学研究表明，COX-1b适合于海洋甘蓝变异的研究。

We examined morphological and morphometric variations in fossils Gephyrocapsa in the Quaternaly in North West Atlantic Ocean, morphometric changes in coccoliths of culture strains of G. oceanica in relation to growth phase, and genetic variation of living G. oceanica in nuclear, plastid and mitcondrial sequences. Morphological studies of fossil Gephyrocapsa showed that fossils of small Gephyrocapsa are varied in morphology of central area, distal shield elements and of bridge angle. Culture experiments revealed that coccoliths produced in stationary phase is larger than log phase, and size range of coccoliths differs between the strains. Molecular study revealed that cox-1b is suitable for the study of variation in G. oceanica.