Editing Coccolithophore (section)

==Ecology==
===Life history strategy===
[[File:Life cycle strategies of phytoplankton.png|thumb|upright=1.7| {{center|Life cycle strategies of phytoplankton}}  (a) [[dinoflagellate]]s tend to utilize a [[haplontic]] (asexual) life cycle, (b) [[diatom]]s tend to utilize a [[diplontic]] (sexual) life cycle, and (c) coccolithophores tend to utilize a haplo-diplontic life cycle. Note that not all coccolithophores calcify in their haploid phase.<ref name="de Vries2021">{{cite journal | last1=de Vries | first1=Joost | last2=Monteiro | first2=Fanny | last3=Wheeler | first3=Glen | last4=Poulton | first4=Alex | last5=Godrijan | first5=Jelena | last6=Cerino | first6=Federica | last7=Malinverno | first7=Elisa | last8=Langer | first8=Gerald | last9=Brownlee | first9=Colin | title=Haplo-diplontic life cycle expands coccolithophore niche | journal=Biogeosciences | publisher=Copernicus GmbH | volume=18 | issue=3 | date=2021-02-16 | issn=1726-4189 | doi=10.5194/bg-18-1161-2021 | pages=1161–1184| bibcode=2021BGeo...18.1161D | s2cid=233976784 | doi-access=free }} [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref>]]

The complex life cycle of coccolithophores is known as a [[Biological life cycle#Haplodiplontic life cycle|haplodiplontic life cycle]], and is characterized by an alternation of both asexual and sexual phases. The asexual phase is known as the [[haploid]] phase, while the sexual phase is known as the [[diploid]] phase. During the haploid phase, coccolithophores produce haploid cells through [[mitosis]]. These haploid cells can then divide further through mitosis or undergo sexual reproduction with other haploid cells. The resulting diploid cell goes through [[meiosis]] to produce haploid cells again, starting the cycle over. With coccolithophores, asexual reproduction by mitosis is possible in both phases of the life cycle, which is a contrast with most other organisms that have alternating life cycles.<ref name="Young2003"/> Both [[abiotic]] and [[biotic factors]] may affect the frequency with which each phase occurs.<ref name=Vardi2012>{{citation |journal=Proceedings of the National Academy of Sciences |volume=109 |issue=47 |year=2012 |pages=19327–19332 |title=Host–virus dynamics and subcellular controls of cell fate in a natural coccolithophore population |first=A. |last=Vardi |doi=10.1073/pnas.1208895109 |pmid=23134731 |display-authors=etal  |bibcode = 2012PNAS..10919327V |pmc=3511156 |doi-access=free }}</ref>

Coccolithophores [[asexual reproduction|reproduce asexually]] through [[Fission (biology)|binary fission.]] In this process the coccoliths from the parent cell are divided between the two daughter cells. There have been suggestions stating the possible presence of a sexual reproduction process due to the diploid stages of the coccolithophores, but this process has never been observed.<ref name=Houdan2006>{{citation |journal=Aquatic Microbial Ecology |volume=44 |year=2006 |pages=291–301 |title=. Ecology of oceanic coccolithophores. I. Nutritional preferences of the two stages in the life cycle of Coccolithus braarudii and Calcidiscus leptoporus |last1=Houdan |doi=10.3354/ame044291|last2=Probert |first2=I |last3=Zatylny |first3=C |last4=Véron |first4=B |last5=Billard |first5=C |display-authors=etal|doi-access=free }}</ref>

[[R/K selection theory|K or r- selected strategies]] of coccolithophores depend on their life cycle stage. When coccolithophores are diploid, they are r-selected. In this phase they tolerate a wider range of nutrient compositions.  When they are haploid they are K- selected and are often more competitive in stable low nutrient environments.<ref name=Houdan2006 /> Most coccolithophores are K strategist and are usually found on nutrient-poor surface waters. They are poor competitors when compared to other phytoplankton and thrive in habitats where other phytoplankton would not survive.<ref name=Hogan2009 /> These two stages in the life cycle of coccolithophores occur seasonally, where more nutrition is available in warmer seasons and less is available in cooler seasons. This type of life cycle is known as a complex heteromorphic life cycle.<ref name=Houdan2006 />

===Global distribution===
[[File:Coccolithophore+Abundance.png|thumb|upright=1.7| Global distribution of coccolithophores in the ocean]]

Coccolithophores occur throughout the world's oceans. Their distribution varies vertically by stratified layers in the ocean and geographically by different temporal zones.<ref name=Geisen2004>{{cite book |last1=Geisen |first1=M. |editor1-first= Hans R. |editor1-last=Thierstein |editor2-first= Jeremy R. |editor2-last=Young |title=Coccolithophores-from molecular processes to global impact |publisher=Springler |date=August 17, 2004 |location=Berlin |chapter=Species level variation in coccolithophores= |isbn=9783540219286 |pages=1–29 |display-authors=etal  }}.</ref> While most modern coccolithophores can be located in their associated stratified [[oligotrophic]] conditions, the most abundant areas of coccolithophores where there is the highest species diversity are located in subtropical zones with a temperate climate.<ref name=Jordan1997>{{citation |journal=Biodiversity & Conservation |volume=6 |issue=1 |year=1997 |pages=131–152 |title=Biodiversity among haptophyte algae |first1=R. W. |last1=Jordan |first2=A.H.L. |last2=Chamberlain|doi=10.1023/A:1018383817777 |s2cid=9564456 }}</ref> While water temperature and the amount of light intensity entering the water's surface are the more influential factors in determining where species are located, the ocean currents also can determine the location where certain species of coccolithophores are found.<ref name=Boeckel2006>{{citation |journal=Deep-Sea Research Part I: Oceanographic Research Papers |volume=53 |issue=6 |year=2006 |pages=1073–1099 |title=Coccolith distribution patterns in South Atlantic and Southern Ocean surface sediments in relation to environmental gradients |last1=Boeckel |doi=10.1016/j.dsr.2005.11.006|last2=Baumann |first2=Karl-Heinz |last3=Henrich |first3=Rüdiger |last4=Kinkel |first4=Hanno |bibcode = 2006DSRI...53.1073B |display-authors=etal}}</ref>

Although motility and colony formation vary according to the life cycle of different coccolithophore species, there is often alternation between a motile, haploid phase, and a non-motile diploid phase.  In both phases, the organism's dispersal is largely due to ocean [[current (ocean)|current]]s and circulation patterns.<ref name=deVargas2007 />

Within the Pacific Ocean, approximately 90 species have been identified with six separate zones relating to different Pacific currents that contain unique groupings of different species of coccolithophores.<ref name=Okada1973>{{citation |journal=Deep-Sea Research and Oceanographic Abstracts  |volume=20 |issue=4 |year=1973 |pages=355–374 |title=The distribution of oceanic coccolithophores in the Pacific |last1=Okada |doi=10.1016/0011-7471(73)90059-4|last2=Honjo |first2=Susumu |bibcode = 1973DSRA...20..355O |display-authors=etal}}</ref> The highest diversity of coccolithophores in the Pacific Ocean was in an area of the ocean considered the Central North Zone which is an area between 30 <sup>o</sup>N and 5 <sup>o</sup>N, composed of the North Equatorial Current and the Equatorial Countercurrent. These two currents move in opposite directions, east and west, allowing for a strong mixing of waters and allowing a large variety of species to populate the area.<ref name=Okada1973 />

In the Atlantic Ocean, the most abundant species are ''[[emiliania huxleyi|E. huxleyi]]'' and ''Florisphaera profunda'' with smaller concentrations of the species ''Umbellosphaera'' ''irregularis'', ''Umbellosphaera tenuis'' and different species of ''Gephyrocapsa''.<ref name=Okada1973 /> Deep-dwelling coccolithophore [[species abundance]] is greatly affected by [[nutricline]] and [[thermocline]] depths. These coccolithophores increase in abundance when the nutricline and thermocline are deep and decrease when they are shallow.<ref name=Kinkel2000>{{citation |journal=Marine Micropaleontology |volume=39 |issue=1–4 |year=2000 |pages=87–112 |title=Coccolithophores in the equatorial Atlantic Ocean: response to seasonal and Late Quaternary surface water variability |first=H. |last=Kinkel |doi=10.1016/s0377-8398(00)00016-5 |display-authors=etal  |bibcode=2000MarMP..39...87K }}</ref>

[[File:Comparative coccolithophore sizes.png|thumb|right|280px|Size comparison between the relatively large coccolithophore ''Scyphosphaera apsteinii'' and the relatively small but ubiquitous coccolithophore ''[[Emiliania huxleyi]]''<ref>Gafar, N. A., Eyre, B. D. and Schulz, K. G. (2019). "A comparison of species specific sensitivities to changing light and carbonate chemistry in calcifying marine phytoplankton". ''Scientific Reports'', '''9'''(1): 1–12. {{doi|10.1038/s41598-019-38661-0}}. [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref>]]

The complete distribution of coccolithophores is currently not known and some regions, such as the Indian Ocean, are not as well studied as other locations in the Pacific and Atlantic Oceans. It is also very hard to explain distributions due to multiple constantly changing factors involving the ocean's properties, such as coastal and equatorial [[upwelling]], frontal systems, [[benthic]] environments, unique oceanic topography, and pockets of isolated high or low water temperatures.<ref name="Young2009"/>
<!-- Deleted image removed: [[File:Table 1Cocco.jpg|frame|alt=Table 1|Table 1. Biogeographic coccolithophorid assemblages; adapted from Jordan, et Al., 1997.<ref name=Jordan1997 />]]
  -- Deleted image removed: [[File:Table 2Cocco.jpg|frame|alt=Table 1|Table 2. Depth-related coccolithophorid assemblages in subtropic waters; adapted from Jordan, et Al., 1997.<ref name=Jordan1997 /> The upper photic zone is low in nutrient concentration, high in light intensity and penetration, and usually higher in temperature. The lower photic zone is high in nutrient concentration, low in light intensity and penetration and relatively cool. The middle photic zone is an area that contains the same values in between that of the lower and upper photic zones.]] -->

The upper photic zone is low in nutrient concentration, high in light intensity and penetration, and usually higher in temperature. The lower photic zone is high in nutrient concentration, low in light intensity and penetration and relatively cool. The middle photic zone is an area that contains the same values in between that of the lower and upper photic zones.<ref name=Jordan1997 />

{{multiple image
 | align     = left
 | direction = horizontal
 | footer    = Larger coccolithophores such as the species above are less numerous than the smaller but ubiquitous ''[[Emiliania huxleyi]]'', but they are heavily calcified and make important contributions to global calcification.<ref>Daniels, C.J., Sheward, R.M. and Poulton, A.J. (2014) "Biogeochemical implications of comparative growth rates of ''Emiliania huxleyi'' and ''Coccolithus'' species". ''Biogeosciences'', '''11'''(23): 6915–6925. {{doi|10.5194/bg-11-6915-2014}}.</ref><ref>Durak, G.M., Taylor, A.R., Walker, C.E., Probert, I., De Vargas, C., Audic, S., Schroeder, D., Brownlee, C. and Wheeler, G.L. (2016) "A role for diatom-like silicon transporters in calcifying coccolithophores". ''Nature communications'', '''7''': 10543. {{doi|10.1038/ncomms10543}}. [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref> Unmarked scale bars 5&nbsp;μm.
 | width1    = 200
 | image1    = Calcidiscus leptoporus.png
 | caption1  = ''Calcidiscus leptoporus''
 | width2    = 188
 | image2    = Coccolithus braarudii.png
 | caption2  = ''[[Coccolithus|Coccolithus braarudii]]''
 | width3    = 212
 | image3    = Scyphosphaera apsteinii.png
 | caption3  = ''Scyphosphaera apsteinii''
}}

{{clear}}

====Great Calcite Belt====
[[File:Great Calcite Belt of the Southern Ocean.webm|thumb|upright=2|Yearly cycle of the [[Great Calcite Belt]] in the Southern Ocean]]
{{Main|Great Calcite Belt}}

The [[Great Calcite Belt]] of the [[Southern Ocean]] is a region of elevated summertime upper ocean calcite concentration derived from coccolithophores, despite the region being known for its [[diatom]] predominance. The overlap of two major phytoplankton groups, coccolithophores and diatoms, in the dynamic frontal systems characteristic of this region provides an ideal setting to study environmental
influences on the distribution of different species within these taxonomic groups.<ref name=Smith2017>{{cite journal |doi = 10.5194/bg-14-4905-2017|title = The influence of environmental variability on the biogeography of coccolithophores and diatoms in the Great Calcite Belt|year = 2017|last1 = Smith|first1 = Helen E. K.|last2 = Poulton|first2 = Alex J.|last3 = Garley|first3 = Rebecca|last4 = Hopkins|first4 = Jason|last5 = Lubelczyk|first5 = Laura C.|last6 = Drapeau|first6 = Dave T.|last7 = Rauschenberg|first7 = Sara|last8 = Twining|first8 = Ben S.|last9 = Bates|first9 = Nicholas R.|last10 = Balch|first10 = William M.|journal = Biogeosciences|volume = 14|issue = 21|pages = 4905–4925|bibcode = 2017BGeo...14.4905S|doi-access = free}} [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref>

The Great Calcite Belt, defined as an elevated [[particulate inorganic carbon]] (PIC) feature occurring alongside seasonally elevated [[chlorophyll a]] in [[Wiktionary:austral|austral]] spring and summer in the Southern Ocean,<ref name=Balch2005>{{cite journal |doi = 10.1029/2004JC002560|title = Calcium carbonate measurements in the surface global ocean based on Moderate-Resolution Imaging Spectroradiometer data|year = 2005|last1 = Balch|first1 = W. M.|last2 = Gordon|first2 = Howard R.|last3 = Bowler|first3 = B. C.|last4 = Drapeau|first4 = D. T.|last5 = Booth|first5 = E. S.|journal = Journal of Geophysical Research|volume = 110|issue = C7|pages = C07001|bibcode = 2005JGRC..110.7001B|doi-access = free}}</ref> plays an important role in climate fluctuations,<ref>{{cite journal |doi = 10.1038/30455|title = Simulated response of the ocean carbon cycle to anthropogenic climate warming|year = 1998|last1 = Sarmiento|first1 = Jorge L.|last2 = Hughes|first2 = Tertia M. C.|last3 = Stouffer|first3 = Ronald J.|last4 = Manabe|first4 = Syukuro|journal = Nature|volume = 393|issue = 6682|pages = 245–249|bibcode = 1998Natur.393..245S|s2cid = 4317429}}</ref><ref>{{cite journal |doi = 10.1029/2003GB002134|title = Response of ocean ecosystems to climate warming|year = 2004|last1 = Sarmiento|first1 = J. L.|last2 = Slater|first2 = R.|last3 = Barber|first3 = R.|last4 = Bopp|first4 = L.|last5 = Doney|first5 = S. C.|last6 = Hirst|first6 = A. C.|last7 = Kleypas|first7 = J.|last8 = Matear|first8 = R.|last9 = Mikolajewicz|first9 = U.|last10 = Monfray|first10 = P.|last11 = Soldatov|first11 = V.|last12 = Spall|first12 = S. A.|last13 = Stouffer|first13 = R.|journal = Global Biogeochemical Cycles|volume = 18|issue = 3|pages = n/a|bibcode = 2004GBioC..18.3003S|hdl = 1912/3392| s2cid=15482539 | url=https://hal.archives-ouvertes.fr/hal-03129787/file/2003GB002134.pdf |hdl-access = free}}</ref> accounting for over 60% of the Southern Ocean area (30–60° S).<ref name=Balch2011>{{cite journal |doi = 10.1029/2011JC006941|title = The contribution of coccolithophores to the optical and inorganic carbon budgets during the Southern Ocean Gas Exchange Experiment: New evidence in support of the "Great Calcite Belt" hypothesis|year = 2011|last1 = Balch|first1 = W. M.|last2 = Drapeau|first2 = D. T.|last3 = Bowler|first3 = B. C.|last4 = Lyczskowski|first4 = E.|last5 = Booth|first5 = E. S.|last6 = Alley|first6 = D.|journal = Journal of Geophysical Research|volume = 116|issue = C4|pages = C00F06|bibcode = 2011JGRC..116.0F06B}}</ref> The region between 30° and 50° S has the highest uptake of anthropogenic carbon dioxide (CO<sub>2</sub>) alongside the North Atlantic and North Pacific oceans.<ref>{{cite journal |doi = 10.1126/science.1097403|title = The Oceanic Sink for Anthropogenic CO2|year = 2004|last1 = Sabine|first1 = C. L.|last2 = Feely|first2 = R. A.|last3 = Gruber|first3 = N.|last4 = Key|first4 = R. M.|last5 = Lee|first5 = K.|last6 = Bullister|first6 = J. L.|last7 = Wanninkhof|first7 = R.|last8 = Wong|first8 = C. S.|last9 = Wallace|first9 = D. W.|last10 = Tilbrook|first10 = B.|last11 = Millero|first11 = F. J.|last12 = Peng|first12 = T. H.|last13 = Kozyr|first13 = A.|last14 = Ono|first14 = T.|last15 = Rios|first15 = A. F.|journal = Science|volume = 305|issue = 5682|pages = 367–371|pmid = 15256665|bibcode = 2004Sci...305..367S|s2cid = 5607281|url = http://oceanrep.geomar.de/46251/1/1193.full.pdf}}</ref>

====Effect of global climate change on distribution====
Recent studies show that climate change has direct and indirect impacts on Coccolithophore distribution and productivity. They will inevitably be affected by the increasing temperatures and thermal stratification of the top layer of the ocean, since these are prime controls on their ecology, although it is not clear whether global warming would result in net increase or decrease of coccolithophores. As they are calcifying organisms, it has been suggested that [[ocean acidification]] due to increasing carbon dioxide could severely affect coccolithophores.<ref name="Kinkel2000"/> Recent {{CO2}} increases have seen a sharp increase in the population of coccolithophores.<ref>{{cite news |url=http://www.csmonitor.com/Science/2015/1128/What-s-fueling-the-rise-of-coccolithophores-in-the-oceans |title=What's fueling the rise of coccolithophores in the oceans? |last1=Gitau |first1=Beatrice |date=28 November 2015 |website=www.csmonitor.com |publisher=The Christian Science Monitor |access-date=30 November 2015}}</ref>

===Role in the food web===
[[File:Bloom in the Barents Sea.jpg|thumb|upright=1.4| Satellite photograph: The milky blue colour of this [[phytoplankton]] bloom in [[Barents Sea]] strongly suggests it contains coccolithophores]]
[[File:Virus cocco 2.jpg|thumb|upright=1.4| A [[coccolithovirus]], ''[[Emiliania huxleyi virus 86]]'' (arrowed), infecting an ''[[Emiliania huxleyi]]'' coccolithophore.<ref name=ViralZone>{{cite web|title=Viral Zone|url=http://viralzone.expasy.org/all_by_species/589.html|publisher=ExPASy|access-date=15 June 2015}}</ref><ref name=ICTV>{{cite web|last1=ICTV|title=Virus Taxonomy: 2014 Release|url=http://ictvonline.org/virusTaxonomy.asp|access-date=15 June 2015}}</ref> This [[giant marine virus]] has one of the largest known [[virus genome]]s.<ref>[http://www.giantvirus.org/top.html Largest known viral genomes] ''Giantviruses.org''. Accessed: 11 June 2020.</ref>]]

Coccolithophores are one of the more abundant primary producers in the ocean.  As such, they are a large contributor to the [[Marine primary production|primary productivity]] of the tropical and subtropical oceans, however, exactly how much has yet to have been recorded.<ref name=Rost2004>{{citation |journal=Coccolithophores |volume=2 |year=2004 |pages=99–125 |title=Coccolithophores and the biological pump: responses to environmental changes |first1=B. |last1=Rost |first2=U. |last2=Riebesell |doi=10.1007/978-3-662-06278-4_5|isbn=978-3-642-06016-8 |url=http://epic.awi.de/11394/1/Ros2004a.pdf |archive-url=https://web.archive.org/web/20121110122119/http://epic.awi.de/11394/1/Ros2004a.pdf |archive-date=2012-11-10 |url-status=live |citeseerx=10.1.1.455.2864 }}</ref>

====Dependence on nutrients====
The ratio between the concentrations of [[nitrogen]], [[phosphorus]] and [[silicate]] in particular areas of the ocean dictates [[Dominance hierarchy|competitive dominance]] within phytoplankton communities. Each ratio essentially tips the odds in favor of either [[diatom]]s or other groups of phytoplankton, such as coccolithophores. A low silicate to nitrogen and phosphorus ratio allows coccolithophores to outcompete other phytoplankton species; however, when silicate to phosphorus to nitrogen ratios are high coccolithophores are outcompeted by diatoms. The increase in agricultural processes lead to [[eutrophication]] of waters and thus, coccolithophore blooms in these high nitrogen and phosphorus, low silicate environments.<ref name="Yunev2007"/>

====Impact on water column productivity====
The [[calcite]] in calcium carbonate allows coccoliths to scatter more light than they absorb. This has two important consequences: 1) Surface waters become brighter, meaning they have a higher [[albedo]], and 2) there is induced [[photoinhibition]], meaning photosythetic production is diminished due to an excess of light.  In case 1), a high concentration of coccoliths leads to a simultaneous increase in surface water temperature and decrease in the temperature of deeper waters. This results in more [[stratification (water)|stratification]] in the water column and a decrease in the vertical mixing of nutrients. However, a 2012 study estimated that the overall effect of coccolithophores on the increase in [[radiative forcing]] of the ocean is less than that from anthropogenic factors.<ref name="Morrissey2012">{{cite book |last1=Morrissey |first1=J.F. |last2=Sumich |first2=J.L. |year=2012 |pages=67 |title=Introduction to the Biology of Marine Life}}</ref> Therefore, the overall result of large blooms of coccolithophores is a decrease in water column productivity, rather than a contribution to global warming.

====Predator-prey interactions====
Their predators include the common predators of all phytoplankton including small fish, zooplankton, and shellfish larvae.<ref name=Hogan2009 /><ref name=Houdan2004>{{citation |journal=Journal of Plankton Research |volume=26 |issue=8 |year=2004 |pages=875–883 |title=Toxicity of coastal coccolithophores (Prymnesiophyceae, Haptophyta)  |first=A. |last=Houdan |doi=10.1093/plankt/fbh079 |display-authors=etal  |doi-access=free }}</ref> Viruses specific to this species have been isolated from several locations worldwide and appear to play a major role in spring bloom dynamics.

=====Toxicity=====
No environmental evidence of coccolithophore toxicity has been reported, but they belong to the class Prymnesiophyceae which contain orders with toxic species. Toxic species have been found in the genera ''Prymnesium'' Massart and ''Chrysochromulina'' Lackey. Members of the genus ''Prymnesium'' have been found to produce haemolytic compounds, the agent responsible for toxicity.  Some of these toxic species are responsible for large fish kills and can be accumulated in organisms such as shellfish; transferring it through the food chain. In laboratory tests for toxicity members of the oceanic coccolithophore genera ''Emiliania, Gephyrocapsa, Calcidiscus'' and ''Coccolithus'' were shown to be non-toxic as were species of the coastal genus ''Hymenomonas'', however several species of ''Pleurochrysis'' and ''Jomonlithus'', both coastal genera were toxic to ''Artemia''.<ref name="Houdan2004"/>

===Community interactions===
Coccolithophorids are predominantly found as single, free-floating haploid or diploid cells.<ref name="Geisen2004"/>

====Competition====
Most [[phytoplankton]] need sunlight and nutrients from the ocean to survive, so they thrive in areas with large inputs of nutrient rich water upwelling from the lower levels of the ocean. Most coccolithophores require sunlight only for energy production, and have a higher ratio of nitrate uptake over ammonium uptake (nitrogen is required for growth and can be used directly from nitrate but not ammonium). Because of this they thrive in still, nutrient-poor environments where other phytoplankton are starving.<ref name=Litchman2007>{{citation |journal=Ecology Letters |volume=10 |issue=12 |year=2007 |pages=1170–1181 |title=The role of functional traits and trade-offs in structuring phytoplankton communities: scaling from cellular to ecosystem level |first= E. |last=Litchman |doi=10.1111/j.1461-0248.2007.01117.x|pmid=17927770  |bibcode=2007EcolL..10.1170L |display-authors=etal  }}</ref> [[Trade-off]]s associated with these faster growth rates include a smaller cell radius and lower cell volume than other types of phytoplankton.

===Viral infection and coevolution===
Giant [[DNA virus|DNA-containing viruses]] are known to [[Lytic Cycle|lytically]] infect coccolithophores, particularly ''E. huxleyi''.  These viruses, known as E. huxleyi viruses (EhVs), appear to infect the coccosphere coated diploid phase of the life cycle almost exclusively.  It has been proposed that as the haploid organism is not infected and therefore not affected by the virus, the co-evolutionary "[[arms race]]" between coccolithophores and these viruses does not follow the classic [[Red Queen's Hypothesis|Red Queen]] evolutionary framework, but instead a "Cheshire Cat" ecological dynamic.<ref name=Frada2008>{{citation |journal=Proceedings of the National Academy of Sciences |volume=105 |issue=41 |year=2008 |pages=15944–15949 |title=The "Cheshire Cat" escape strategy of the coccolithophore ''Emiliania huxleyi'' in response to viral infection |first=M. |last=Frada |doi=10.1073/pnas.0807707105 |display-authors=etal  |bibcode = 2008PNAS..10515944F |pmid=18824682 |pmc=2572935|doi-access=free }}</ref>  More recent work has suggested that viral synthesis of [[sphingolipids]] and induction of [[programmed cell death]] provides a more direct link to study a Red Queen-like [[coevolution]]ary arms race at least between the coccolithoviruses and diploid organism.<ref name="Vardi2012"/>