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1. Developmental bias, macroevolution, and the fossil record.

   https://doi.org/10.1111/ede.12313  

   Jablonski, D. (January 2020, Evolution development)

   null (Ed.)

   A fuller understanding of the role of developmental bias in shaping large-scale evolutionary patterns requires integrating bias (the probability distribution of variation accessible to an ancestral phenotype) with clade dynamics (the differential survival and production of species and evolutionary lineages). This synthesis could proceed as a two-way exchange between the developmental data available to neontologists and the strictly phenotypic but richly historical and dynamic data available to paleontologists. Analyses starting in extant populations could aim to predict macroevolution in the fossil record from observed developmental bias, while analyses starting in the fossil record, particularly the record of extant species and lineages, could aim to predict developmental bias from macroevolutionary patterns, including the broad range of extinct phenotypes. Analyses in multivariate morphospaces are especially effective when coupled with phylogeny, theoretical and developmental models, and diversity–disparity plots. This research program will also require assessing the “heritability” of an ancestral bias across phylogeny, and the tendency for bias change in strength and orientation over evolutionary time. Such analyses will help find a set of general rules for the macroevolutionary effects of developmental bias, including its impact on and interactions with the other intrinsic and extrinsic factors governing the movement, expansion, and contraction of clades in morphospace. 

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2. Diversity-Disparity Dynamics Vary Significantly Across Major Marine Animal Clades

   https://doi.org/10.1130/abs/2025AM-8185  

   Novack-Gottshall, Philip (January 2025, Geological Society of America)

   Decades of studying disparity have yielded few consistent patterns regarding the morphological and ecological impacts during major diversifications. Early bursts can accrue innovation more rapidly than the number of radiating lineages, disparity can expand in a concordant fashion with a clade's diversification, or disparity can lag behind diversity. In a series of papers in Evolutionary Biology, David Jablonski (1997a,b, 2022) proposed using "diversity-disparity plots" to more systematically document these dynamics, regardless of clade, time interval, or environmental circumstance. Drawing on a database of the life habits of all marine genera in the Paleobiology Database, here I compare diversity-disparity dynamics for major clades (phyla and classes) throughout their evolutionary histories. Most clades have volatile Phanerozoic diversity-disparity trends that move idiosyncratically throughout this space. Several clades—including trilobites, chondrichthyans, crinoids, and echinoids—have trends that fall close to the 1:1 line, suggesting ecological innovation generally tracks lineage diversity in these taxa. Clades with higher-than-expected evolvability include arthropods (especially malacostracans), gymnolaemates, and Paleozoic chordates and mollusks, while those exemplifying lower evolvability include Paleozoic echinoderms and post-Paleozoic chordates. The wide range of diversity-disparity trends observed among marine taxa suggests clade-specific limits to evolvability rather than generalizable artifacts of evolutionary diversification. This research has been supported by NSF grant #2322080. 

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3. Mode of miniaturisation influences body shape evolution in New World Anchovies (Engraulidae)

   https://doi.org/10.1111/jfb.14205  

   Bloom, D.D.; Kolmann, M.A.; Foster, K.; Watrous, H. (January 2020, Journal of fish biology)

   We explored the macroevolutionary dynamics of miniaturisation in New World anchovies by integrating a time-calibrated phylogeny, geometric morphometrics and phylogenetic comparative methods. We found that the paedomorphic species Amazonsprattus scintilla occupies a novel region of shape space, while the dwarf species Anchoviella manamensis has an overall shape consistent with other anchovies. We found that miniaturisation did not increase overall clade disparity in size or shape beyond the expectations of Brownian motion, nor were there differences in rates of size or shape evolution among clades. Overall, our study shows that while the mode of miniaturisation influences shape evolution, the phenotypic novelty produced by the evolution of miniaturisation did not seem to alter macroevolutionary dynamics. 

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4. Approaches to macroevolution: 2. Sorting of variation, some overarching issues, and general conclusions.

   Jablonski, D. (July 2017, Evolutionary biology)

   Abstract Approaches to macroevolution require integration of its two fundamental components, within a hierarchical framework. Following a companion paper on the origin of variation, I here discuss sorting within an evolutionary hierarchy. Species sorting—sometimes termed species selection in the broad sense, meaning differential origination and extinction owing to intrinsic biological properties—can be split into strict-sense species selection, in which rate differentials are governed by emergent, species-level traits such as geographic range size, and effect macroevolution, in which rates are governed by organism-level traits such as body size; both processes can create hitchhiking effects, indirectly causing the proliferation or decline of other traits. Several methods can operationalize the concept of emergence, so that rigorous separation of these processes is increasingly feasible. A macroevolutionary tradeoff, underlain by the intrinsic traits that influence evolutionary dynamics, causes speciation and extinction rates to covary in many clades, resulting in evolutionary volatility of some clades and more subdued behavior of others; the few clades that break the tradeoff can achieve especially prolific diversification. In addition to intrinsic biological traits at multiple levels, extrinsic events can drive the waxing and waning of clades, and the interaction of traits and events are difficult but important to disentangle. Evolutionary trends can arise in many ways, and at any hierarchical level; descriptive models can be fitted to clade trajectories in phenotypic or functional spaces, but they may not be diagnostic regarding processes, and close attention must be paid to both leading and trailingedges of apparent trends. Biotic interactions can have negative or positive effects on taxonomic diversity within a clade, but cannot be readily extrapolated from the nature of such interactions at the organismic level. The relationships among macroevolutionary currencies through time (taxonomic richness, morphologic disparity, functional variety) are crucial for understanding the nature of evolutionary diversification. A novel approach to diversity-disparity analysis shows that taxonomic diversifications can lag behind, occur in concert with, or precede, increases in disparity. Some overarching issues relating to both the origin and sorting of clades and phenotypes include the macroevolutionary role of mass extinctions, the potential differences between plant and animal macroevolution, whether macroevolutionary processes have changed through geologic time, and the growing human impact on present-day macroevolution. Many challenges remain, but progress is being made on two of the key ones: (a) the integration of variation-generating mechanisms and the multilevel sorting processes that act on that variation, and (b) the integration of paleontological and neontological approaches to historical biology. 

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5. Transitions Into Freezing Environments Linked With Shifts in Phylogenetic Integration Between Vitaceae Leaf Traits

   https://doi.org/10.1002/ece3.70553  

   Parins‐Fukuchi, Charles Tomo; Stull, Gregory W; Wen, Jun; Beaulieu, Jeremy M (November 2024, Ecology and Evolution)

   ABSTRACT Understanding how the intrinsic ability of populations and species to meet shifting selective demands shapes evolutionary patterns over both short and long timescales is a major question in biology. One major axis of evolutionary flexibility can be measured by phenotypic integration and modularity. The strength, scale, and structure of integration may constrain or catalyze evolution in the face of new selective pressures. We analyze a dataset of seven leaf measurements across Vitaceae to examine how correlations in trait divergence are linked to transitions between freezing and nonfreezing habitats. We assess this by applying a custom algorithm to compare the timing of habitat shifts to changes in the structure of evolutionary trait correlation at discrete points along a phylogeny. We also explore these patterns in relation to lineage diversification rates to understand how and whether patterns in the evolvability of complex multivariate phenotypes are linked to higher‐level macroevolutionary dynamics. We found that shifts in the structure, but not the overall strength, of phylogenetic integration of leaves precipitate colonization of freezing climates. Lineages that underwent associated shifts in leaf trait integration and subsequent movement into freezing habitats also displayed lower turnover and higher net diversification, suggesting a link among shifting vectors of selection, internal constraint, and lineage persistence in the face of changing environments. 

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