Phyletic gradualism

@misc{eldredge1972punctuated1,
    author = "Eldredge, N. and Gould, S. J",
    title = "Punctuated Equilibria",
    year = "1972",
    howpublished = "An Alternative to Phyletic Gradualism, in Schopf, T. M., ed., Models in Paleobiology: San Francisco, Freeman, Cooper, \& Co., p. 82-115; 250 pp",
    note = "talkorigins\_source = {true}; raw\_reference = {Eldredge, N., and Gould, S. J., 1972, Punctuated Equilibria: An Alternative to Phyletic Gradualism, in Schopf, T. M., ed., Models in Paleobiology: San Francisco, Freeman, Cooper, \& Co., p. 82-115; 250 pp.}"
}

@article{gingerich1980evolutionary2,
    author = "Gingerich, P. D",
    title = "Evolutionary patterns in early Cenozoic mammals",
    year = "1980",
    journal = "Annual Review of Earth and Planetary Sciences, v. 8, p. 407-424",
    note = "talkorigins\_source = {true}; raw\_reference = {Gingerich, P. D., 1980, Evolutionary patterns in early Cenozoic mammals: Annual Review of Earth and Planetary Sciences, v. 8, p. 407-424.}"
}

An equation for the distribution of divergence times between closest relatives is derived to explore the possibility that contemporary data might shed some light on the controversy between supporters of gradual versus punctuated phyletic change. The principal assumptions of the model are uniform rates of speciation and extinction, bifurcating speciation, and uniform patterns of divergence, by whatever measure, among species in a taxon. The structure of the model indicates clear differences between patterns generated by extremes of gradualism and punctuation. But inability to verify critical assumptions considerably weakens the applicability of the model to the gradualism-punctuation problem.

@article{ricklefs1980phyletic,
    author = "Ricklefs, Robert E.",
    title = "Phyletic gradualism vs. punctuated equilibrium: applicability of neontological data",
    year = "1980",
    journal = "Paleobiology",
    abstract = "An equation for the distribution of divergence times between closest relatives is derived to explore the possibility that contemporary data might shed some light on the controversy between supporters of gradual versus punctuated phyletic change. The principal assumptions of the model are uniform rates of speciation and extinction, bifurcating speciation, and uniform patterns of divergence, by whatever measure, among species in a taxon. The structure of the model indicates clear differences between patterns generated by extremes of gradualism and punctuation. But inability to verify critical assumptions considerably weakens the applicability of the model to the gradualism-punctuation problem.",
    url = "https://doi.org/10.1017/s0094837300006795",
    doi = "10.1017/s0094837300006795",
    number = "3",
    pages = "271-275",
    volume = "6"
}

Shape measurements have been made on planktonic foraminifera from a South Pacific Late Miocene to Recent temperate evolutionary lineage (Globorotalia conoidea through intermediate forms to G. inflata in DSDP Site 284). The sampling interval is about 0.1 Myr over nearly 8 Myr. Gradual evolution (phyletic gradualism) clearly occurs in all but one measured parameter. No clear evidence exists for abrupt evolutionary steps (punctuated equilibria) within the bioseries. If they occur, they are the exception rather than the rule. The number of chambers in the final whorl decreases almost linearly, despite known paleoceanographic oscillations within the temperate water mass. Mean size and apertural shape variations seem to correlate with paleoceanographic change. It is speculated that certain major morphological changes that took place within this evolutionary bioseries (i.e. loss of keel, rounding of periphery) developed in response to a major latest Miocene cooling, associated with instability in the water column and resulting adjustments of the test structure to water density changes. Changes exhibited in shape measurements may offer a precise method of stratigraphic correlation between temperate South Pacific Late Cenozoic sequences. Four species and two subspecies, long recognized to form the basis of this lineage, are redefined biometrically.

@article{malmgren1981phyletic,
    author = "Malmgren, Björn A. and Kennett, James P.",
    title = "Phyletic gradualism in a Late Cenozoic planktonic foraminiferal lineage; DSDP Site 284, southwest Pacific",
    year = "1981",
    journal = "Paleobiology",
    abstract = "Shape measurements have been made on planktonic foraminifera from a South Pacific Late Miocene to Recent temperate evolutionary lineage (Globorotalia conoidea through intermediate forms to G. inflata in DSDP Site 284). The sampling interval is about 0.1 Myr over nearly 8 Myr. Gradual evolution (phyletic gradualism) clearly occurs in all but one measured parameter. No clear evidence exists for abrupt evolutionary steps (punctuated equilibria) within the bioseries. If they occur, they are the exception rather than the rule. The number of chambers in the final whorl decreases almost linearly, despite known paleoceanographic oscillations within the temperate water mass. Mean size and apertural shape variations seem to correlate with paleoceanographic change. It is speculated that certain major morphological changes that took place within this evolutionary bioseries (i.e. loss of keel, rounding of periphery) developed in response to a major latest Miocene cooling, associated with instability in the water column and resulting adjustments of the test structure to water density changes. Changes exhibited in shape measurements may offer a precise method of stratigraphic correlation between temperate South Pacific Late Cenozoic sequences. Four species and two subspecies, long recognized to form the basis of this lineage, are redefined biometrically.",
    url = "https://doi.org/10.1017/s0094837300004000",
    doi = "10.1017/s0094837300004000",
    number = "2",
    pages = "230-240",
    volume = "7"
}

@book{gould1984toward3,
    author = "Gould, S. J",
    title = "Toward the Vindication of Punctuational Change, in Berggren, W. A., and Van Couvering, J. A., eds., Catastrophes and Earth History",
    year = "1984",
    publisher = "The New Uniformitarianism: Princeton, New Jersey, Princeton University Press, p. 9-34",
    note = "talkorigins\_source = {true}; raw\_reference = {Gould, S. J., 1984, Toward the Vindication of Punctuational Change, in Berggren, W. A., and Van Couvering, J. A., eds., Catastrophes and Earth History: The New Uniformitarianism: Princeton, New Jersey, Princeton University Press, p. 9-34.}"
}

@article{raup1985catastrophes,
    author = "Raup, David M.",
    title = "Catastrophes and Earth History. W. A. Berggren, John A. Van Couvering",
    year = "1985",
    journal = "The Journal of Geology",
    url = "https://doi.org/10.1086/628945",
    doi = "10.1086/628945",
    number = "2",
    pages = "221-221",
    volume = "93"
}

@incollection{barnosky1987punctuated,
    author = "Barnosky, Anthony D.",
    title = "Punctuated Equilibrium and Phyletic Gradualism",
    year = "1987",
    booktitle = "Current Mammalogy",
    url = "https://doi.org/10.1007/978-1-4757-9909-5\_4",
    doi = "10.1007/978-1-4757-9909-5\_4",
    pages = "109-147"
}

Este libro, editado por W. A. Berggren y A. Van Couvering, sobre Catástrofes e Historia de la Tierra está parcialmente basado en dos simposios sobre temas relacionados, uno en el Instituto Oceanográfico de Woods Hole, junio de 1977, y el otro en Lawrence, Kansas, durante la Convención Paleontológica de Norteamérica, agosto de 1977.

@article{urrutiafucugauchi1988catastrophes,
    author = "Urrutia Fucugauchi, J.",
    title = "Catastrophes and Earth history / W. A. Berggren y A. Van Couvering, eds.",
    year = "1988",
    journal = "Geofísica Internacional",
    abstract = "Este libro, editado por W. A. Berggren y A. Van Couvering, sobre Catástrofes e Historia de la Tierra está parcialmente basado en dos simposios sobre temas relacionados, uno en el Instituto Oceanográfico de Woods Hole, junio de 1977, y el otro en Lawrence, Kansas, durante la Convención Paleontológica de Norteamérica, agosto de 1977.",
    url = "https://doi.org/10.22201/igeof.00167169p.1988.27.2.1196",
    doi = "10.22201/igeof.00167169p.1988.27.2.1196",
    number = "2",
    pages = "299-301",
    volume = "27"
}

@incollection{crossref1989appendix,
    title = "APPENDIX: Punctuated Equilibria: An Alternative to Phyletic Gradualism",
    year = "1989",
    booktitle = "Time Frames",
    url = "https://doi.org/10.1515/9781400860296.193",
    doi = "10.1515/9781400860296.193",
    pages = "193-224"
}

@article{willis1998broccoli,
    author = "Willis, K.J",
    title = "Broccoli and phyletic gradualism",
    year = "1998",
    journal = "Trends in Ecology \& Evolution",
    url = "https://doi.org/10.1016/s0169-5347(97)01264-0",
    doi = "10.1016/s0169-5347(97)01264-0",
    number = "1",
    pages = "37-38",
    volume = "13"
}

Punctuated equilibrium and phyletic gradualism are contrasting patterns of evolution among a spectrum of patterns found in the fossil record. In punctuated equilibrium, species tend to show morphological stasis between abrupt speciation events, whereas in phyletic gradualism species undergo more continuous change.

@misc{sheldon2001punctuated,
    author = "Sheldon, Peter R",
    title = "Punctuated Equilibrium and Phyletic Gradualism",
    year = "2001",
    booktitle = "Encyclopedia of Life Sciences",
    abstract = "Punctuated equilibrium and phyletic gradualism are contrasting patterns of evolution among a spectrum of patterns found in the fossil record. In punctuated equilibrium, species tend to show morphological stasis between abrupt speciation events, whereas in phyletic gradualism species undergo more continuous change.",
    url = "https://doi.org/10.1038/npg.els.0001774",
    doi = "10.1038/npg.els.0001774"
}

@misc{crossref2014phyletic,
    title = "PHYLETIC GRADUALISM",
    year = "2014",
    booktitle = "Encyclopedia of Environmental Change",
    url = "https://doi.org/10.4135/9781446247501.n2968",
    doi = "10.4135/9781446247501.n2968"
}

@inproceedings{andsprinkle2022teaching,
    author = "Sprinkle, James",
    title = "TEACHING PUNCTUATED EQUILIBRIUM VS. PHYLETIC GRADUALISM:1972-2012",
    year = "2022",
    booktitle = "Geological Society of America Abstracts with Programs",
    url = "https://doi.org/10.1130/abs/2022am-378048",
    doi = "10.1130/abs/2022am-378048"
}