Davis Catherine V, Livsey Caitlin M, Palmer Hannah M, Hull Pincelli M, Thomas Ellen, Hill Tessa M, Benitez-Nelson Claudia R
Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA.
School of the Earth, Ocean and Environment, University of South Carolina, Columbia, SC, USA.
Sci Adv. 2020 Jul 10;6(28). doi: 10.1126/sciadv.abb8930. Print 2020 Jul.
Marine protists are integral to the structure and function of pelagic ecosystems and marine carbon cycling, with rhizarian biomass alone accounting for more than half of all mesozooplankton in the oligotrophic oceans. Yet, understanding how their environment shapes diversity within species and across taxa is limited by a paucity of observations of heritability and life history. Here, we present observations of asexual reproduction, morphologic plasticity, and ontogeny in the planktic foraminifer in laboratory culture. Our results demonstrate that planktic foraminifera reproduce both sexually and asexually and demonstrate extensive phenotypic plasticity in response to nonheritable factors. These two processes fundamentally explain the rapid spatial and temporal response of even imperceptibly low populations of planktic foraminifera to optimal conditions and the diversity and ubiquity of these species across the range of environmental conditions that occur in the ocean.
海洋原生生物对于远洋生态系统的结构和功能以及海洋碳循环至关重要，仅根足虫生物量就占贫营养海洋中所有中型浮游动物的一半以上。然而，由于关于遗传力和生活史的观测数据匮乏，我们对环境如何塑造物种内和跨分类群的多样性的理解受到限制。在这里，我们展示了在实验室培养中对浮游有孔虫的无性繁殖、形态可塑性和个体发育的观测结果。我们的结果表明，浮游有孔虫进行有性和无性繁殖，并对非遗传因素表现出广泛的表型可塑性。这两个过程从根本上解释了即使是数量少到难以察觉的浮游有孔虫种群对最佳条件的快速时空响应，以及这些物种在海洋中出现的各种环境条件下的多样性和普遍性。
