Paleogene

@article{loeblich1961cretaceous,
    author = "Loeblich, Alfred R. and Tappan, Helen",
    title = "Cretaceous Planktonic Foraminifera: Part I. Cenomanian",
    year = "1961",
    journal = "Micropaleontology",
    url = "https://doi.org/10.2307/1484364",
    doi = "10.2307/1484364",
    number = "3",
    pages = "257",
    volume = "7"
}

@misc{berggren1962stratigraphic1,
    author = "Berggren, W. A",
    title = "Stratigraphic and taxonomic-phylogenetic studies of Upper Cretaceous and Paleogene planktonic Foraminifera",
    year = "1962",
    howpublished = "Stockholm Contributions to Geology, v. 9, p. 107-129",
    note = "talkorigins\_source = {true}; raw\_reference = {Berggren, W. A., 1962, Stratigraphic and taxonomic-phylogenetic studies of Upper Cretaceous and Paleogene planktonic Foraminifera: Stockholm Contributions to Geology, v. 9, p. 107-129.}"
}

@incollection{krasheninnikov1973late,
    author = "Krasheninnikov, V.A. and Hoskins, R.H.",
    title = "Late Cretaceous, Paleogene and Neogene Planktonic Foraminifera",
    year = "1973",
    booktitle = "Initial Reports of the Deep Sea Drilling Project",
    url = "https://doi.org/10.2973/dsdp.proc.20.110.1973",
    doi = "10.2973/dsdp.proc.20.110.1973"
}

@incollection{krasheninnikov1974cretaceous,
    author = "Krasheninnikov, V.A.",
    title = "Cretaceous and Paleogene Planktonic Foraminifera, Leg 27 of the Deep Sea Drilling Project",
    year = "1974",
    booktitle = "Initial Reports of the Deep Sea Drilling Project",
    url = "https://doi.org/10.2973/dsdp.proc.27.133.1974",
    doi = "10.2973/dsdp.proc.27.133.1974"
}

@article{dhondt1991phylogenetic,
    author = "d'Hondt, S. L.",
    title = "Phylogenetic and stratigraphic analysis of earliest Paleocene biserial and triserial planktonic foraminifera",
    year = "1991",
    journal = "The Journal of Foraminiferal Research",
    url = "https://doi.org/10.2113/gsjfr.21.2.168",
    doi = "10.2113/gsjfr.21.2.168",
    number = "2",
    pages = "168-181",
    volume = "21"
}

@article{qianyu1991evolution,
    author = "Qianyu, Li and Radford, Sally S.",
    title = "Evolution and biogeography of Paleogene microperforate planktonic foraminifera",
    year = "1991",
    journal = "Palaeogeography, Palaeoclimatology, Palaeoecology",
    url = "https://doi.org/10.1016/0031-0182(91)90077-5",
    doi = "10.1016/0031-0182(91)90077-5",
    number = "1-3",
    pages = "87-115",
    volume = "83"
}

@article{radford1991innovations,
    author = "Radford, Sally and Gamson, Paul and Qianyu, Li",
    title = "Innovations among Paleogene planktonic foraminifera",
    year = "1991",
    journal = "Historical Biology",
    url = "https://doi.org/10.1080/10292389109380413",
    doi = "10.1080/10292389109380413",
    number = "2-4",
    pages = "363-367",
    volume = "5"
}

@article{peryt1993the,
    author = "Peryt, D. and Lahodynsky, R. and Rocchia, R. and Boclet, D.",
    title = "The cretaceous/paleogene boundary and planktonic foraminifera in the flyschgosau (Eastern Alps, Austria)",
    year = "1993",
    journal = "Palaeogeography, Palaeoclimatology, Palaeoecology",
    url = "https://doi.org/10.1016/0031-0182(93)90135-6",
    doi = "10.1016/0031-0182(93)90135-6",
    number = "1-4",
    pages = "239-252",
    volume = "104"
}

@article{georgescu2006taxonomic,
    author = "Georgescu, Marius D. and Huber, Brian T.",
    title = "Taxonomic revision of coarsely ornamented Upper Cretaceous trochospiral planktonic foraminifera",
    year = "2006",
    journal = "Anuário do Instituto de Geociências",
    url = "https://doi.org/10.11137/2006\_1\_330-331",
    doi = "10.11137/2006\_1\_330-331",
    number = "1",
    pages = "330-331",
    volume = "29"
}

The biotic crisis following the end-Cretaceous asteroid impact resulted in a dramatic renewal of pelagic biodiversity. Considering the severe and immediate effect of the asteroid impact on the pelagic environment, it is remarkable that some of the most affected pelagic groups, like the planktonic foraminifera, survived at all. Here we queried a surface ocean metabarcoding dataset to show that calcareous benthic foraminifera of the clade Globothalamea are able to disperse actively in the plankton, and we show using molecular clock phylogeny that the modern planktonic clades originated from different benthic ancestors that colonized the plankton after the end-Cretaceous crisis. We conclude that the diversity of planktonic foraminifera has been the result of a constant leakage of benthic foraminifera diversity into the plankton, continuously refueling the planktonic niche, and challenge the classical interpretation of the fossil record that suggests that Mesozoic planktonic foraminifera gave rise to the modern communities.

@article{morard2022renewal,
    author = "Morard, Raphaël and Hassenrück, Christiane and Greco, Mattia and Fernandez-Guerra, Antonio and Rigaud, Sylvain and Douady, Christophe J. and Kucera, Michal",
    title = "Renewal of planktonic foraminifera diversity after the Cretaceous Paleogene mass extinction by benthic colonizers",
    year = "2022",
    journal = "Nature Communications",
    abstract = "The biotic crisis following the end-Cretaceous asteroid impact resulted in a dramatic renewal of pelagic biodiversity. Considering the severe and immediate effect of the asteroid impact on the pelagic environment, it is remarkable that some of the most affected pelagic groups, like the planktonic foraminifera, survived at all. Here we queried a surface ocean metabarcoding dataset to show that calcareous benthic foraminifera of the clade Globothalamea are able to disperse actively in the plankton, and we show using molecular clock phylogeny that the modern planktonic clades originated from different benthic ancestors that colonized the plankton after the end-Cretaceous crisis. We conclude that the diversity of planktonic foraminifera has been the result of a constant leakage of benthic foraminifera diversity into the plankton, continuously refueling the planktonic niche, and challenge the classical interpretation of the fossil record that suggests that Mesozoic planktonic foraminifera gave rise to the modern communities.",
    url = "https://doi.org/10.1038/s41467-022-34794-5",
    doi = "10.1038/s41467-022-34794-5",
    number = "1",
    volume = "13"
}

Muricate planktonic foraminifera comprise an extinct clade that was diverse and abundant in the Paleogene oceans and are widely used in palaeoclimate research as geochemical proxy carriers for the upper oceans. Their characteristic wall texture has surface projections called “muricae” formed by upward deflection and mounding of successive layers of the test wall. The group is generally considered to have lacked “true spines”: that is, acicular calcite crystals embedded in and projecting from the test surface such as occur in many modern and some Paleogene groups. Here we present evidence from polished sections, surface wall scanning electron microscope images and test dissections, showing that radially orientated crystalline spine-like structures occur in the centre of muricae in various species of Acarinina and Morozovella and projected from the test wall in life. Their morphology and placement in the wall suggest that they evolved independently of true spines. Nevertheless, they may have served a similar range of functions as spines in modern species, including aiding buoyancy and predation and especially harbouring algal photosymbionts, the function for which we suggest they probably first evolved. Our observations strengthen the analogy between Paleogene mixed-layer-dwelling planktonic foraminifera and their modern spinose counterparts.

@article{pearson2022spinelike,
    author = "Pearson, Paul N. and John, Eleanor and Wade, Bridget S. and D'haenens, Simon and Lear, Caroline H.",
    title = "Spine-like structures in Paleogene muricate planktonic foraminifera",
    year = "2022",
    journal = "Journal of Micropalaeontology",
    abstract = "Muricate planktonic foraminifera comprise an extinct clade that was diverse and abundant in the Paleogene oceans and are widely used in palaeoclimate research as geochemical proxy carriers for the upper oceans. Their characteristic wall texture has surface projections called “muricae” formed by upward deflection and mounding of successive layers of the test wall. The group is generally considered to have lacked “true spines”: that is, acicular calcite crystals embedded in and projecting from the test surface such as occur in many modern and some Paleogene groups. Here we present evidence from polished sections, surface wall scanning electron microscope images and test dissections, showing that radially orientated crystalline spine-like structures occur in the centre of muricae in various species of Acarinina and Morozovella and projected from the test wall in life. Their morphology and placement in the wall suggest that they evolved independently of true spines. Nevertheless, they may have served a similar range of functions as spines in modern species, including aiding buoyancy and predation and especially harbouring algal photosymbionts, the function for which we suggest they probably first evolved. Our observations strengthen the analogy between Paleogene mixed-layer-dwelling planktonic foraminifera and their modern spinose counterparts.",
    url = "https://doi.org/10.5194/jm-41-107-2022",
    doi = "10.5194/jm-41-107-2022",
    number = "2",
    pages = "107-127",
    volume = "41"
}