@article{doi101111j155856461971tb01868x, author = "Eldredge, Niles", title = "THE ALLOPATRIC MODEL AND PHYLOGENY IN PALEOZOIC INVERTEBRATES", year = "1971", journal = "Evolution", abstract = "Journal Article THE ALLOPATRIC MODEL AND PHYLOGENY IN PALEOZOIC INVERTEBRATES Get access Niles Eldredge Niles Eldredge The American Museum of Natural History Central Park West at 79th New York New York 10024 Search for other works by this author on: Oxford Academic Google Scholar Evolution, Volume 25, Issue 1, 1 March 1971, Pages 156–167, https://doi.org/10.1111/j.1558-5646.1971.tb01868.x Published: 01 March 1971 Article history Received: 10 June 1970 Published: 01 March 1971", url = "https://doi.org/10.1111/j.1558-5646.1971.tb01868.x", doi = "10.1111/j.1558-5646.1971.tb01868.x", openalex = "W2312476507", references = "carruthers1910on, doi10100797814615958542, doi101017s0022336000062466, doi101086282596, doi101111j155856461949tb00003x, doi101126science15938191065, doi101144gsljgs1910066010428, doi1011632666064403801010, doi1023071794238, doi1023072412347, kermack1954a, openalexw1522518756, waller1969the" } @article{doi101017s0094837300005662, author = "Stanley, Steven M.", title = "Chronospecies' longevities, the origin of genera, and the punctuational model of evolution", year = "1978", journal = "Paleobiology", abstract = "Taxonomists working with late Cenozoic faunas tend to view living species as starting points for the evaluation of chronospecies (i.e., segments of evolutionary lineages subjectively designated as species) that extend backward in time from the Recent. This practice makes it possible to construct a survivorship curve for late Cenozoic chronospecies by evaluating all fossil lineages believed to have survived to the present day. A survivorship curve is produced by plotting the fraction of these lineages existing at any time that have not undergone enough phyletic evolution that their extant representatives are assigned to new species. This kind of surviviorship curve has been plotted for chronospecies of mammals using the beginning of the Würm, rather than the Recent, as an endpoint in order to avoid the effects of the Würm and post-Würm mass extinction. The survivorship curve reveals that all but a small fraction of established chronospecies have long durations relative to intervals of time during which distinctive higher taxa have arisen. Phyletic turnover of species has been remarkably slow. Most net evolutionary change must have been associated with saltational speciation. Even the large majority of genera must have arisen rapidly by one or more divergent speciation events. Estimates of rates of extinction suggest that the bottleneck effect, in which constriction of a lineage is followed by re-expansion as a distinct species, cannot be a major source of evolutionary change. These conclusions, based on the evaluation of mammalian phylogeny, seem also to apply to other taxa of animals, supporting the punctuational model of evolution. The long durations of hominid species imply that the evolution of humans, like that of other mammals, conforms to this model.", url = "https://doi.org/10.1017/s0094837300005662", doi = "10.1017/s0094837300005662", openalex = "W2484245196", references = "doi10100703064746897, doi101017s0094837300005224, doi101093aesa383396, doi101126science1653891349, doi1023071441916, doi1023072407738, doi1023072411924, doi104159harvard9780674865327, openalexw2145250129, openalexw3135630760" } @article{stanley1978chronospecies, author = "Stanley, Steven M.", title = "Chronospecies' longevities, the origin of genera, and the punctuational model of evolution", year = "1978", journal = "Paleobiology", abstract = "Taxonomists working with late Cenozoic faunas tend to view living species as starting points for the evaluation of chronospecies (i.e., segments of evolutionary lineages subjectively designated as species) that extend backward in time from the Recent. This practice makes it possible to construct a survivorship curve for late Cenozoic chronospecies by evaluating all fossil lineages believed to have survived to the present day. A survivorship curve is produced by plotting the fraction of these lineages existing at any time that have not undergone enough phyletic evolution that their extant representatives are assigned to new species. This kind of surviviorship curve has been plotted for chronospecies of mammals using the beginning of the Würm, rather than the Recent, as an endpoint in order to avoid the effects of the Würm and post-Würm mass extinction. The survivorship curve reveals that all but a small fraction of established chronospecies have long durations relative to intervals of time during which distinctive higher taxa have arisen. Phyletic turnover of species has been remarkably slow. Most net evolutionary change must have been associated with saltational speciation. Even the large majority of genera must have arisen rapidly by one or more divergent speciation events. Estimates of rates of extinction suggest that the bottleneck effect, in which constriction of a lineage is followed by re-expansion as a distinct species, cannot be a major source of evolutionary change. These conclusions, based on the evaluation of mammalian phylogeny, seem also to apply to other taxa of animals, supporting the punctuational model of evolution. The long durations of hominid species imply that the evolution of humans, like that of other mammals, conforms to this model.", url = "https://doi.org/10.1017/s0094837300005662", doi = "10.1017/s0094837300005662", number = "1", openalex = "W2484245196", pages = "26-40", volume = "4", references = "doi10100703064746897, doi101017s0094837300005224, doi101093aesa383396, doi101126science1653891349, doi1023071441916, doi1023072407738, doi1023072411924, doi104159harvard9780674865327, openalexw2145250129, openalexw3135630760" } @misc{stanley1978chronospecies1, author = "Stanley, S. M", title = "Chronospecies' longevities, the origin of genera, and the punctuational model of evolution", year = "1978", howpublished = "Paleobiology, v. 4, p. 26-40", note = "talkorigins\_source = {true}; raw\_reference = {Stanley, S. M., 1978, Chronospecies' longevities, the origin of genera, and the punctuational model of evolution: Paleobiology, v. 4, p. 26-40.}" } @article{stanley1989the, author = "Stanley, Steven M", title = "The empirical case for the punctuational model of evolution", year = "1989", journal = "Journal of Social and Biological Structures", url = "https://doi.org/10.1016/0140-1750(89)90042-0", doi = "10.1016/0140-1750(89)90042-0", number = "2-3", openalex = "W2038851461", pages = "159-172", volume = "12", references = "doi101017s0094837300005224, doi101038325031a0, doi101086282975, doi101093genetics16297, doi101093genetics9441011, doi101111j155856461969tb03508x, doi1023072482053, doi104159harvard9780674865327, doi107312steb94536, openalexw2971318137" } @article{doi101103physrevlett714083, author = "Bak, Per and Sneppen, Kim", title = "Punctuated equilibrium and criticality in a simple model of evolution", year = "1993", journal = "Physical Review Letters", abstract = "A simple and robust model of biological evolution of an ecology of interacting species is introduced. The model self-organizes into a critical steady state with intermittent coevolutionary avalanches of all sizes; i.e., it exhibits ``punctuated equilibrium'' behavior. This collaborative evolution is much faster than non-cooperative scenarios since no large and coordinated, and hence prohibitively unlikely, mutations are involved.", url = "https://doi.org/10.1103/physrevlett.71.4083", doi = "10.1103/physrevlett.71.4083", openalex = "W1966151890", references = "doi1010160004698180901493, doi101016s0022519305800943, doi101017s0094837300005224, doi101038342780a0, doi101103physreva38364, doi101103physreva466724, doi101103physrevlett59381, doi101103physrevlett693539, doi101103physrevlett71101, doi1012019780429492594, pines2018emerging" } @incollection{clube1996evolution, author = "Clube, S. V. M.", title = "Evolution, Punctuational Crises and the Threat to Civilization", year = "1996", booktitle = "Worlds in Interaction: Small Bodies and Planets of the Solar System", url = "https://doi.org/10.1007/978-94-009-0209-1\_54", doi = "10.1007/978-94-009-0209-1\_54", openalex = "W2078463644", pages = "433-440", references = "doi1010079789401133784, doi101007bf00049549, doi101038363704a0, doi101038367033a0, doi101146annurevea11050183002333, doi101177095968369400400211, doi1023071782931, doi1023073901804, doi105860choice330281, openalexw1638717326" } @article{doi101103physreve66011904, author = "Hall, Matt and Christensen, Kim and di Collobiano, Simone A. and Jensen, Henrik Jeldtoft", title = "Time-dependent extinction rate and species abundance in a tangled-nature model of biological evolution", year = "2002", journal = "Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics", abstract = "We present a model of evolutionary ecology consisting of a web of interacting individuals, a tangle-nature model. The reproduction rate of individuals characterized by their genome depends on the composition of the population in genotype space. Ecological features such as the taxonomy and the macroevolutionary mode of the dynamics are emergent properties. The macrodynamics exhibit intermittent two-mode switching with a gradually decreasing extinction rate. The generated ecologies become gradually better adapted as well as more complex in a collective sense. The form of the species abundance curve compares well with observed functional forms. The model's error threshold can be understood in terms of the characteristics of the two dynamical modes of the system.", url = "https://doi.org/10.1103/physreve.66.011904", doi = "10.1103/physreve.66.011904", openalex = "W1968938483", references = "doi101111j155856461971tb01868x" } @article{doi101016jtree200310013, author = "Johnson, Jerald B. and Omland, Kristian Shawn", title = "Model selection in ecology and evolution", year = "2003", journal = "Trends in Ecology \& Evolution", url = "https://doi.org/10.1016/j.tree.2003.10.013", doi = "10.1016/j.tree.2003.10.013", openalex = "W2146081698", references = "doi101007978146121694015, doi10108000063659909477239, doi101080106351501753462876, doi101093genetics1551431, doi101126science1065889, doi101126science1483671754, doi101146annurevge22120188002513, doi1023072937171, doi1023073802723, doi1023073803199, doi105860choice351501, doi105860choice375647, openalexw1546962148, openalexw3041231242" } @article{crossref2006gradual, title = "Gradual Versus Punctuational Evolution", year = "2006", journal = "Science", url = "https://doi.org/10.1126/science.314.5796.13g", doi = "10.1126/science.314.5796.13g", number = "5796", openalex = "W4210646514", pages = "13g-13g", volume = "314" } @article{doi101126science1129647, author = "Pagel, Mark and Venditti, Chris and Meade, Andrew", title = "Large Punctuational Contribution of Speciation to Evolutionary Divergence at the Molecular Level", year = "2006", journal = "Science", abstract = "A long-standing debate in evolutionary biology concerns whether species diverge gradually through time or by punctuational episodes at the time of speciation. We found that approximately 22\% of substitutional changes at the DNA level can be attributed to punctuational evolution, and the remainder accumulates from background gradual divergence. Punctuational effects occur at more than twice the rate in plants and fungi than in animals, but the proportion of total divergence attributable to punctuational change does not vary among these groups. Punctuational changes cause departures from a clock-like tempo of evolution, suggesting that they should be accounted for in deriving dates from phylogenies. Punctuational episodes of evolution may play a larger role in promoting evolutionary divergence than has previously been appreciated.", url = "https://doi.org/10.1126/science.1129647", doi = "10.1126/science.1129647", openalex = "W2084825432", references = "doi101111j155856461971tb01868x" } @article{doi101007s116920129171x, author = "Rosenblum, Erica Bree and Sarver, Brice A. J. and Brown, Joseph W. and Roches, Simone Des and Hardwick, Kayla M. and Hether, Tyler and Eastman, Jonathan M. and Pennell, Matthew W. and Harmon, Luke J.", title = "Goldilocks Meets Santa Rosalia: An Ephemeral Speciation Model Explains Patterns of Diversification Across Time Scales", year = "2012", journal = "Evolutionary Biology", abstract = {Understanding the rate at which new species form is a key question in studying the evolution of life on earth. Here we review our current understanding of speciation rates, focusing on studies based on the fossil record, phylogenies, and mathematical models. We find that speciation rates estimated from these different studies can be dramatically different: some studies find that new species form quickly and often, while others find that new species form much less frequently. We suggest that instead of being contradictory, differences in speciation rates across different scales can be reconciled by a common model. Under the "ephemeral speciation model", speciation is very common and very rapid but the new species produced almost never persist. Evolutionary studies should therefore focus on not only the formation but also the persistence of new species.}, url = "https://doi.org/10.1007/s11692-012-9171-x", doi = "10.1007/s11692-012-9171-x", openalex = "W1997489023", references = "doi101016jtree200611004, doi101017s0094837300005662, doi10108010635150600852011, doi101086282070, doi101093aesa383396, doi101093oso97801985052350010001, doi1023073071998, doi102307jctv1nzfgj7, doi104159harvard9780674865327, doi105860choice375647, openalexw2764433274, stanley1978chronospecies" } @article{doi101371journalpone0109210, author = "Wright, April and Hillis, David M.", title = "Bayesian Analysis Using a Simple Likelihood Model Outperforms Parsimony for Estimation of Phylogeny from Discrete Morphological Data", year = "2014", journal = "PLoS ONE", abstract = "Despite the introduction of likelihood-based methods for estimating phylogenetic trees from phenotypic data, parsimony remains the most widely-used optimality criterion for building trees from discrete morphological data. However, it has been known for decades that there are regions of solution space in which parsimony is a poor estimator of tree topology. Numerous software implementations of likelihood-based models for the estimation of phylogeny from discrete morphological data exist, especially for the Mk model of discrete character evolution. Here we explore the efficacy of Bayesian estimation of phylogeny, using the Mk model, under conditions that are commonly encountered in paleontological studies. Using simulated data, we describe the relative performances of parsimony and the Mk model under a range of realistic conditions that include common scenarios of missing data and rate heterogeneity.", url = "https://doi.org/10.1371/journal.pone.0109210", doi = "10.1371/journal.pone.0109210", openalex = "W2067046632", references = "doi10108010635150802022231, doi101111j10963642200600293x, doi101111j15585646201201723x" } @article{doi101073pnas1403662111, author = "Hunt, Gene and Hopkins, Melanie J. and Lidgard, Scott", title = "Simple versus complex models of trait evolution and stasis as a response to environmental change", year = "2015", journal = "Proceedings of the National Academy of Sciences", abstract = "Previous analyses of evolutionary patterns, or modes, in fossil lineages have focused overwhelmingly on three simple models: stasis, random walks, and directional evolution. Here we use likelihood methods to fit an expanded set of evolutionary models to a large compilation of ancestor-descendant series of populations from the fossil record. In addition to the standard three models, we assess more complex models with punctuations and shifts from one evolutionary mode to another. As in previous studies, we find that stasis is common in the fossil record, as is a strict version of stasis that entails no real evolutionary changes. Incidence of directional evolution is relatively low (13\%), but higher than in previous studies because our analytical approach can more sensitively detect noisy trends. Complex evolutionary models are often favored, overwhelmingly so for sequences comprising many samples. This finding is consistent with evolutionary dynamics that are, in reality, more complex than any of the models we consider. Furthermore, the timing of shifts in evolutionary dynamics varies among traits measured from the same series. Finally, we use our empirical collection of evolutionary sequences and a long and highly resolved proxy for global climate to inform simulations in which traits adaptively track temperature changes over time. When realistically calibrated, we find that this simple model can reproduce important aspects of our paleontological results. We conclude that observed paleontological patterns, including the prevalence of stasis, need not be inconsistent with adaptive evolution, even in the face of unstable physical environments.", url = "https://doi.org/10.1073/pnas.1403662111", doi = "10.1073/pnas.1403662111", openalex = "W2157019229", references = "doi101002bimj200810425, doi10100703064746897, doi101017s0094837300005224, doi1010292004pa001071, doi101046j14724642199900046x, doi101086303400, doi101093aesa383396, doi1023072485224, doi105860choice396411, openalexw3135630760, stanley1989the" } @article{doi1011112041210x12420, author = "Clavel, Julien and Escarguel, Gilles and Merceron, Gildas", title = "mv morph: an r package for fitting multivariate evolutionary models to morphometric data", year = "2015", journal = "Methods in Ecology and Evolution", abstract = "Summary We present mv morph, a package of multivariate phylogenetic comparative methods for the r statistical environment. mv morph is freely available on the cran package repository (http://cran.r-project.org/web/packages/mvMORPH/). mv morph allows fitting a range of multivariate evolutionary models under a maximum‐likelihood criterion. Initially developed in the context of phylogenetic analysis of multiple morphometric traits, its use can be extended to any biological data set with one or multiple covarying continuous traits. All the fitting models include the possibility to use simmap ‐like mapping, which may be useful for fitting changes along lineages at a given point in time. All models provide diagnostic metrics for convergence and reliability of estimates, as well as the possibility to include trait measurement errors in model estimates. New features provided by the mv morph package include the possibility of fitting models with changes in the mode of evolution along the phylogeny, which will be particularly meaningful in comparative analyses that include extinct taxa, for example when testing changes in evolutionary mode associated with global biotic/abiotic events. We briefly describe the models already included in mv morph and provide some demonstration of the use of the package with two simulated worked examples.", url = "https://doi.org/10.1111/2041-210x.12420", doi = "10.1111/2041-210x.12420", openalex = "W1527504944", references = "doi1010079783662024522, doi1010079783662053898, doi10103844766, doi101086284325, doi101086383584, doi1011112041210x12035, doi101111j001438202003tb00285x, doi101111j155856461979tb04694x, doi101111j155856461983tb00236x, doi101111j15585646201201723x, doi101111j2041210x201100169x, doi10118614712105788, doi1023073802723" } @article{doi101111ele12398, author = "Warren, Ben H. and Simberloff, Daniel and Ricklefs, Robert E. and Aguilée, Robin and Condamine, Fabien L. and Gravel, Dominique and Morlon, Hélène and Mouquet, Nicolas and Rosindell, James and Casquet, Juliane and Conti, Elena and Cornuault, Josselin and Fernández‐Palacios, José María and Hengl, Tomislav and Norder, Sietze J. and Rijsdijk, Kenneth F. and Sanmartín, Isabel and Strasberg, Dominique and Triantis, Kostas A. and Valente, Luís and Whittaker, Robert J. and Gillespie, Rosemary G. and Emerson, Brent C. and Thébaud, Christophe", title = "Islands as model systems in ecology and evolution: prospects fifty years after MacArthur‐Wilson", year = "2015", journal = "Ecology Letters", abstract = "The study of islands as model systems has played an important role in the development of evolutionary and ecological theory. The 50th anniversary of MacArthur and Wilson's (December 1963) article, 'An equilibrium theory of insular zoogeography', was a recent milestone for this theme. Since 1963, island systems have provided new insights into the formation of ecological communities. Here, building on such developments, we highlight prospects for research on islands to improve our understanding of the ecology and evolution of communities in general. Throughout, we emphasise how attributes of islands combine to provide unusual research opportunities, the implications of which stretch far beyond islands. Molecular tools and increasing data acquisition now permit re-assessment of some fundamental issues that interested MacArthur and Wilson. These include the formation of ecological networks, species abundance distributions, and the contribution of evolution to community assembly. We also extend our prospects to other fields of ecology and evolution - understanding ecosystem functioning, speciation and diversification - frequently employing assets of oceanic islands in inferring the geographic area within which evolution has occurred, and potential barriers to gene flow. Although island-based theory is continually being enriched, incorporating non-equilibrium dynamics is identified as a major challenge for the future.", url = "https://doi.org/10.1111/ele.12398", doi = "10.1111/ele.12398", openalex = "W2156521347", references = "doi101038nature07893, doi101038nrg3644, doi101126science1157966, doi101126science1193954" } @article{doi101016jtree201811009, author = "Pontarp, Mikael and Bunnefeld, Lynsey and Cabral, Juliano Sarmento and Etienne, Rampal S. and Fritz, Susanne A. and Gillespie, Rosemary G. and Graham, Catherine H. and Hagen, Oskar and Härtig, Florian and Huang, Shan and Jansson, Roland and Maliet, Odile and Münkemüller, Tamara and Pellissier, Loïc and Rangel, Thiago F. and Štorch, David and Wiegand, Thorsten and Hurlbert, Allen H.", title = "The Latitudinal Diversity Gradient: Novel Understanding through Mechanistic Eco-evolutionary Models", year = "2018", journal = "Trends in Ecology \& Evolution", url = "https://doi.org/10.1016/j.tree.2018.11.009", doi = "10.1016/j.tree.2018.11.009", openalex = "W2906409355", references = "doi101016jtree201309012, doi101146annurevecolsys112414054102" } @article{doi101126scienceaar5452, author = "Rangel, Thiago F. and Edwards, Neil R. and Holden, Philip B. and Diniz‐Filho, José Alexandre Felizola and Gosling, William D. and Coelho, Marco Túlio Pacheco and Cassemiro, Fernanda A. S. and Rahbek, Carsten and Colwell, Robert K.", title = "Modeling the ecology and evolution of biodiversity: Biogeographical cradles, museums, and graves", year = "2018", journal = "Science", abstract = "Individual processes shaping geographical patterns of biodiversity are increasingly understood, but their complex interactions on broad spatial and temporal scales remain beyond the reach of analytical models and traditional experiments. To meet this challenge, we built a spatially explicit, mechanistic simulation model implementing adaptation, range shifts, fragmentation, speciation, dispersal, competition, and extinction, driven by modeled climates of the past 800,000 years in South America. Experimental topographic smoothing confirmed the impact of climate heterogeneity on diversification. The simulations identified regions and episodes of speciation (cradles), persistence (museums), and extinction (graves). Although the simulations had no target pattern and were not parameterized with empirical data, emerging richness maps closely resembled contemporary maps for major taxa, confirming powerful roles for evolution and diversification driven by topography and climate.", url = "https://doi.org/10.1126/science.aar5452", doi = "10.1126/science.aar5452", openalex = "W2885016372", references = "doi101002joc1276, doi10100797894010058529, doi101016jtree201208024, doi101016jtree201406005, doi1010292004pa001071, doi101038nature22897, doi101046j14429993200101070x, doi101093genetics1312479, doi101111j14429993200101070ppx, doi101126science13134091292, doi101126scienceaac4315, doi101146annurevecolsys110308120327, doi101146annurevecolsys33010802150448, doi101371journalpone0103958, doi1015159780691209418, doi1023072485224, doi105962bhltitle82303" } @article{butler2025punctuational, author = "Butler, George and Amend, Sarah R. and Venditti, Chris and Pienta, Kenneth J.", title = "Punctuational evolution is pervasive in distal site metastatic colonization", year = "2025", journal = "Proceedings of the Royal Society B: Biological Sciences", abstract = "The evolution of metastasis, the spread of cancer to distal sites within the body, represents a lethal stage of cancer progression. Yet, the evolutionary dynamics that shape the emergence of metastatic disease remain unresolved. Here, using single-cell lineage tracing data in combination with phylogenetic statistical methods, we show that the evolutionary trajectory of metastatic disease is littered with bursts of rapid molecular change as new cellular subpopulations appear, a pattern known as punctuational evolution. Next, by measuring punctuational evolution across the metastatic cascade, we show that punctuational effects are concentrated within the formation of secondary tumours at distal metastatic sites, suggesting that qualitatively different modes of evolution may drive primary and metastatic tumour progression. Taken as a whole, our findings provide empirical evidence for distinct patterns of molecular evolution at early and late stages of metastatic disease and our approach provides a framework to study the evolution of metastasis at a more nuanced level than has been previously possible.", url = "https://doi.org/10.1098/rspb.2024.2850", doi = "10.1098/rspb.2024.2850", number = "2039", openalex = "W4406640873", volume = "292", references = "doi101007bf00160154, doi101016jcell201303021, doi101016jcell201611037, doi101017s0094837300005224, doi10103844766, doi101038nature10762, doi101038nature14347, doi101056nejmoa1616288, doi10108010635150490522232, openalexw3135630760" } @article{doi101017pab202510058, author = "Stanley, Steven M.", title = "Why the punctuational model of evolution is valid", year = "2025", journal = "Paleobiology", abstract = "Abstract I have devised two tests that pit punctuationalism against gradualism. The first is the Test of Adaptive Radiation, which I apply to families of middle Eocene Mammalia and Late Cretaceous Bivalvia. This test shows that species in both of these classes lasted much too long for evolution within them (phyletic evolution) to have produced the new families that arose during brief time intervals. This test would yield similar results for many other taxa. It supports the punctuational model, as does the Test of Living Fossils, which predicts that long, slender clades, having experienced little speciation, should have undergone little evolution. Limited largely to phyletic evolution, this is exactly what happened to them. Several multivariate morphological studies of numerous fossil lineages have found little or no gradual evolution to have been the norm. One of these included 153 lineage traits and another, 250. Still another produced a rectangular stratophenetic phylogeny, with inferred horizontal speciation events connecting vertical lineages. Taken together these studies provide overwhelming support for the punctuational model. Many studies have shown that rapid speciation events occur frequently and some are punctuational. Jellyfishes that have appeared recently in saltwater lakes on the Pacific island of Palau are remarkable examples of punctuational speciation, and so is the sudden appearance of the novel sand dollar family Dendrasteridae in the California Miocene. The punctuational model shows that the value of sexual reproduction must be in producing long-lived adaptive radiations, whereas clones die out quickly.", url = "https://doi.org/10.1017/pab.2025.10058", doi = "10.1017/pab.2025.10058", openalex = "W4416981381", references = "doi101007s100219900037, doi101073pnas0704088104, doi101073pnas722646, doi101111j001438202004tb01740x, doi101111j155856461971tb01868x, doi101126science28854691211, doi101579004474472912, doi101890024045, doi107312simp93764, doi107312steb94536" } @article{stanley2025why, author = "Stanley, Steven M.", title = "Why the punctuational model of evolution is valid", year = "2025", journal = "Paleobiology", abstract = "I have devised two tests that pit punctuationalism against gradualism. The first is the Test of Adaptive Radiation, which I apply to families of middle Eocene Mammalia and Late Cretaceous Bivalvia. This test shows that species in both of these classes lasted much too long for evolution within them (phyletic evolution) to have produced the new families that arose during brief time intervals. This test would yield similar results for many other taxa. It supports the punctuational model, as does the Test of Living Fossils, which predicts that long, slender clades, having experienced little speciation, should have undergone little evolution. Limited largely to phyletic evolution, this is exactly what happened to them. Several multivariate morphological studies of numerous fossil lineages have found little or no gradual evolution to have been the norm. One of these included 153 lineage traits and another, 250. Still another produced a rectangular stratophenetic phylogeny, with inferred horizontal speciation events connecting vertical lineages. Taken together these studies provide overwhelming support for the punctuational model. Many studies have shown that rapid speciation events occur frequently and some are punctuational. Jellyfishes that have appeared recently in saltwater lakes on the Pacific island of Palau are remarkable examples of punctuational speciation, and so is the sudden appearance of the novel sand dollar family Dendrasteridae in the California Miocene. The punctuational model shows that the value of sexual reproduction must be in producing long-lived adaptive radiations, whereas clones die out quickly.", url = "https://doi.org/10.1017/pab.2025.10058", doi = "10.1017/pab.2025.10058", number = "4", openalex = "W4416981381", pages = "631-644", volume = "51", references = "doi101007s100219900037, doi101073pnas0704088104, doi101073pnas722646, doi101111j001438202004tb01740x, doi101111j155856461971tb01868x, doi101126science28854691211, doi101579004474472912, doi101890024045, doi107312simp93764, doi107312steb94536" }