@article {sucheras-marx_coccolith_2022,
	title = {Coccolith size rules {\textendash} What controls the size of coccoliths during coccolithogenesis?},
	journal = {Marine Micropaleontology},
	volume = {170},
	year = {2022},
	pages = {102080},
	abstract = {Heterococcoliths are calcite platelets produced inside diploid coccolithophore cells and extruded to form a covering on the cell surface called a coccosphere. The size of coccoliths is an important parameter sometimes used to identify species, and it is observed to be influenced in extant species by abiotic parameters (e.g., CO2, light). However, the variable distribution of coccolith sizes occurring within a single coccosphere questions the mechanisms controlling coccolith size. A relationship between cell/coccosphere size and mean coccolith size was previously identified, called the {\textquotedblleft}coccolithophore size rules{\textquotedblright}. In this study, we query the mechanisms controlling the size of a coccolith during coccolithogenesis. A culture experiment on Gephyrocapsa huxleyi strain RCC1216 shows that coccolithogenesis occurs during the cell growth G1 interphase and newly produced coccoliths get bigger as the cell grows. These observations provide parameters for the development of two numerical models used to simulate the coccolith size distribution within a coccolithophore population. Neither model can accurately reproduce an empirical monoclonal coccolith size distribution, indicating that additional factors influence coccolith size. According to our results, coccolith size is only clearly related to cell size at the time of its formation. We confirm that application of the coccolithophore size rules model should be limited to inferring average cell dimensions from (fossil) coccolith biometry, and that comparisons are valid only in multipopulational studies. The coccolith size rule model {\textendash} the constraining effect of coccolith production during G1 interphase cell growth on coccolith size {\textendash} proposed here is applicable only for some placolith-forming species.},
	keywords = {Biometry, coccolith, coccolithophore, life cycle, RCC1216, Size variation},
	issn = {0377-8398},
	doi = {10.1016/j.marmicro.2021.102080},
	url = {https://www.sciencedirect.com/science/article/pii/S0377839821001213},
	author = {Such{\'e}ras-Marx, Baptiste and Viseur, Sophie and Walker, Charlotte E. and Beaufort, Luc and Probert, Ian and Bolton, Clara}
}
@article {langer_role_2021,
	title = {Role of silicon in the development of complex crystal shapes in coccolithophores},
	journal = {New Phytologist},
	volume = {231},
	number = {5},
	year = {2021},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/nph.17230},
	pages = {1845{\textendash}1857},
	abstract = {The development of calcification by the coccolithophores had a profound impact on ocean carbon cycling, but the evolutionary steps leading to the formation of these complex biomineralized structures are not clear. Heterococcoliths consisting of intricately shaped calcite crystals are formed intracellularly by the diploid life cycle phase. Holococcoliths consisting of simple rhombic crystals can be produced by the haploid life cycle stage but are thought to be formed extracellularly, representing an independent evolutionary origin of calcification. We use advanced microscopy techniques to determine the nature of coccolith formation and complex crystal formation in coccolithophore life cycle stages. We find that holococcoliths are formed in intracellular compartments in a similar manner to heterococcoliths. However, we show that silicon is not required for holococcolith formation and that the requirement for silicon in certain coccolithophore species relates specifically to the process of crystal morphogenesis in heterococcoliths. We therefore propose an evolutionary scheme in which the lower complexity holococcoliths represent an ancestral form of calcification in coccolithophores. The subsequent recruitment of a silicon-dependent mechanism for crystal morphogenesis in the diploid life cycle stage led to the emergence of the intricately shaped heterococcoliths, enabling the formation of the elaborate coccospheres that underpin the ecological success of coccolithophores.},
	keywords = {biomineralization, Calcification, coccolith, coccolithophore, evolution, rcc, RCC1178, RCC1181, RCC1456, RCC1460, RCC1461, RCC1477, RCC1800, RCC1801, RCC3777, RCC6506, silicon},
	issn = {1469-8137},
	doi = {10.1111/nph.17230},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/nph.17230},
	author = {Langer, Gerald and Taylor, Alison R. and Walker, Charlotte E. and Meyer, Erin M. and Ben Joseph, Oz and Gal, Assaf and Harper, Glenn M. and Probert, Ian and Brownlee, Colin and Wheeler, Glen L.}
}
@article {Meyer2020,
	title = {Sr in coccoliths of Scyphosphaera apsteinii: Partitioning behavior and role in coccolith morphogenesis},
	journal = {Geochimica et Cosmochimica Acta},
	volume = {285},
	year = {2020},
	note = {Publisher: Elsevier Ltd tex.mendeley-tags: RCC1456},
	month = {sep},
	pages = {41{\textendash}54},
	abstract = {Coccolithophores are important contributors to global calcium carbonate through their species-specific production of calcite coccoliths. Nannofossil coccolith calcite remains an important tool for paleoreconstructions through geochemical analysis of isotopic and trace element incorporation including Sr, which is a potential indicator of past surface ocean temperature and productivity. Scyphosphaera apsteinii (Zygodiscales) exhibits an unusually high Sr/Ca ratio and correspondingly high partitioning coefficient (DSr = 2.5) in their two morphologically distinct types of coccoliths: flat muroliths and barrel-like lopadoliths. Whether or not this reflects mechanistic differences in calcification compared to other coccolithophores is unknown. We therefore examined the possible role of Sr in S. apsteinii calcification by growing cells in deplete (0.33 mmol/mol Sr/Ca), ambient (9 mmol/mol Sr/Ca), and higher than ambient Sr conditions (36 and 72 mmol/mol Sr/Ca). The effects on growth, quantum efficiency of photosystem II (Fv/Fm), coccolith morphology, and calcite DSr were evaluated. No effect on S. apsteinii growth rate or Fv/Fm was observed when cells were grown in Sr/Ca between 0.33{\textendash}36 mmol/mol. However, at 72 mmol/mol Sr/Ca growth rate was significantly reduced, although Fv/Fm was unaffected. Reducing the Sr/Ca from ambient (9 mmol/mol) did not significantly alter the frequency of malformed and aberrant muroliths and lopadoliths, but at higher than ambient Sr/Ca conditions coccolith morphology was significantly disrupted. This implies that Sr is not a critical determining factor in normal coccolith calcite morphology in this dimorphic species. Using energy dispersive spectroscopy (EDS) we observed an increase in [Sr] and decrease in DSr of coccoliths as the Sr/Ca of the growth medium increased. Interestingly, muroliths had significantly lower Sr/Ca than lopadoliths at ambient and elevated [Sr], and lopadolith tips had lower Sr than bases in ambient conditions. In summary, the Sr fractionation behavior of S. apsteinii is distinct from other coccolithophores because of an unusually high DSr and inter- and intra-coccolith variability in Sr/Ca. These observations could be explained by mechanistic differences in the selectivity of the Ca2+ transport pathway or in the Sr-and Ca-binding capacity of organic components, such as polysaccharides associated with coccolithogenesis.},
	keywords = {biomineralization, Calcification, coccolith, coccolithophore, Energy dispersive spectroscopy, Fractionation, RCC1456, Sr/Ca, Strontium, Trace element},
	issn = {00167037},
	doi = {10.1016/j.gca.2020.06.023},
	author = {Meyer, Erin M. and Langer, Gerald and Brownlee, Colin and Wheeler, Glen L. and Taylor, Alison R.}
}
@article {Fox2018,
	title = {Calcein staining as a tool to investigate coccolithophore calcification},
	journal = {Frontiers in Marine Science},
	volume = {5},
	number = {September},
	year = {2018},
	note = {tex.mendeley-tags: RCC 1461,RCC 3777,RCC1130,RCC1303,RCC1456},
	abstract = {This brief paper summarizes the literature on academic accommodations for students with psychiatric disabilities. A definition of psychiatric disability precedes a brief summary of the following specific psychiatric diagnoses: depression, bipolar affective disorder; borderline personality disorder; schizophrenia; and anxiety disorders. Also noted are behavior or personality disorders specifically excluded from coverage under the Americans with Disabilities Act. Functional limitations of this population that may affect academic performance are then listed and defined. Among these are medication side effects, sustaining concentration, maintaining stamina, interacting with others, responding to negative feedback, responding to change, and severe test anxiety. Examples of appropriate instructional strategies are followed by a discussion of reasonable accommodations to provide these students with equal access to the curriculum. Examples are then given of classroom accommodations, examination accommodations, and assignment accommodations. Characteristics of accommodations that are not reasonable are also listed. The paper concludes with a resource list including Web site and contact information for the DO-IT (Disabilities, Opportunities, Internetworking, and Technology) Project. (DB)},
	keywords = {bet hedging, calcein, Calcification, coccolith, coccolithophore, flow cytometry, haptophyte, RCC1130, RCC1303, RCC1456, RCC1461, RCC3777, secretion},
	issn = {2296-7745},
	doi = {10.3389/fmars.2018.00326},
	url = {https://www.frontiersin.org/article/10.3389/fmars.2018.00326/full},
	author = {Fox, Emily and Meyer, Erin and Panasiak, Natalie and Taylor, Alison R.}
}
