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Abstract Over the interval 2008–2023 a large number of studies have been published testing various aspects of punctuated equilibria, including the prevalence of stasis, and also the extent to which most evolutionary change is concentrated at cladogenesis. In the vast majority of studies, punctuated equilibria continued to be strongly validated, as widespread evidence for stasis accumulated, with only some rare incidences of gradual change found. Support for the importance of cladogenetic change has increased, and new analytical approaches to study punctuated equilibria have been developed. Over this time period, there has also been an increase in the number of studies that have concentrated on extant taxa to test for punctuated equilibria, and these have also corroborated its widespread presence. In this respect, punctuated equilibria has served as an important bridge between neontological and paleontological approaches to evolutionary biology. From 2008 to 2023, there has also been some drift in how stasis is defined, such that, in certain studies, the definition diverged from the original 1972 definition in important respects. Notably, it is the few studies that have most changed the definition of what stasis constitutes that have most challenged the validity of punctuated equilibria, indicating it is morphing interpretations and definitions rather than the discovery of data compatible with phyletic gradualism that are most responsible for divergent results. 

Predicting the effects of anthropogenic climate change on Earth’s marine mollusk species is highly relevant, as many are critical human food resources and indispensable members of marine ecosystems. To predict which species will go extinct and which will survive, it is essential to understand the past climate species have experienced, as well as determine the relationship between functional traits, which provide a direct connection to organismal ecology, and survival. Many extant West Atlantic (WA) mollusks, especially gastropods and bivalves, survived the Mid-Pliocene Warm Period and the Last Interglacial, warm intervals compared to the present, that can serve as analogues for predicted future conditions of anthropogenic climate change. WA mollusks have an exceptional Neogene fossil record, which makes them an ideal group to study to develop a predictive extinction risk framework. The present research focuses on the correlation between functional traits and extinction in over 80 species of WA mollusks, both extant and extinct. Functional trait data such as body size, mobility, diet, bathymetric depth range, and organism-substrate relationship, which correlate with metabolic requirements, a known factor in extinction risk, and degree and type of ornamentation, shell shape in bivalves, and narrowness of the aperture in gastropods, which correlate with predation resistance, were collected across these species. These comprise both continuous and discrete character data. Various statistical tests were applied to the database to examine variable correlation/interaction, and the relative contributions of traits to extinction risk. Traits related to metabolism were strong predictors of survival; traits related to predation resistance play a less important role. While this study focuses on organismic traits, the aim of future research will be to explore how group characteristics such as geographic range are associated with functional traits and extinction risk for these species. A predictive framework is developed using patterns of extinction in the fossil record to infer survival of various species in the future, which will be relevant for evaluating the potential consequences of climate change, global change biology, and for determining which species should be targeted for conservation efforts. 

Identifying competitive exclusion at the macroevolutionary scale has typically relied on demonstrating a reciprocal, contradictory response by two co-occurring, functionally similar clades. Finding definitive examples of such a response in fossil time series has proven challenging, however, as has controlling for the effects of a changing physical environment. We take a novel approach to this issue by quantifying variation in trait values that capture almost the entirety of function for steam locomotives (SL), a known example of competitive exclusion from material culture, with the goal of identifying patterns suitable for assessing clade replacement in the fossil record. Our analyses find evidence of an immediate, directional response to the first appearance of a direct competitor, with subsequent competitors further reducing the realized niche of SLs, until extinction was the inevitable outcome. These results demonstrate when interspecific competition should lead to extinction and suggest that clade replacement may only occur when niche overlap between an incumbent and its competitors is near absolute and where the incumbent is incapable of transitioning to a new adaptive zone. Our findings provide the basis for a new approach to analyse putative examples of competitive exclusion that is largely free ofa prioriassumptions.