Emiliania Huxleyi: Role of the Scaled Flagellate in the Life Cycle and Bloom Dynamics

自晚更新世起源以来，>Emiliania huxleyi> 在海洋中无处不在。 它是最丰富的 活的颗石藻，也是地球上最重要的生物， 大气中的二氧化碳转移到海洋沉积物中。 形态上有颗石型、着生型和裸颗型 细胞和鳞片状鞭毛虫。 只有颗石。方位 形态型在天然样品中是容易识别的，并且所有 迄今为止对物种分布和丰度的研究 都只研究过这种形态 较于其他 颗石藻表明能动的形式是一种交替的生命 循环阶段，但>Emiliania hyxleyi>的生活史仍然存在 了解甚少，其在水华动力学中的作用是未知的。 最近开发的技术允许识别和跟踪 裸和鞭毛>Emliliania huyxleyi>细胞在自然 种群和简化确定倍性的培养 细胞 本研究的目的是（1）比较 鞭毛型的丰度和分布与 自然种群中的球形体在形成之前、期间和之后， 开花，（2）建立倍性和生活史，从而 (3)以确定鞭毛形式的作用， Bloom Dynamics中的重组。

Since its origin in the late Pleistocene, >Emiliania huxleyi> has become ubiquitous in the world's oceans. It is the most abundant living coccolithophore and the most important organism in the transfer of atmospheric carbon dioxide to the ocean sediments. Morphological forms include coccolith.bearing and naked coccoid cells, and scaled flagellates. Only the coccolith.bearing morphotype is readily identifiable in natural samples, and all studies to date on the distribution and abundance of the species have been studies of only this morphotype. Comparison to other coccolithophores suggests the motile form is an alternate life cycle stage, but the life cycle of >Emiliania hyxleyi> remains poorly understood, and its role in bloom dynamics is unknown. Recently developed techniques permit identification and tracking of naked and flagellated >Emliliania huyxleyi> cells in natural populations and simplify determination of ploidy in cultured cells. The objectives of this research are (1) to compare the abundances and distributions of the flagellated form to that of the coccoid forms in natural populations before, during and after blooms, (2) to establish ploidy and the life history, and thus (3) to determine the role of the flagellated form, and of sexual recombination, in bloom dynamics.