Intraspecific phenotypic variation provides the basic substrate upon which the evolutionary processes that give rise to morphological innovation, such as adaptation, operate. Work in living clades has shown standing population-level variation fuels ecological speciation and gives rise to adaptive radiations. Despite its importance in evolutionary biology, the role of intraspecific variation in shaping phylogenetic and macroevolutionary patterns and processes has remained underexplored.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
March 2025
Paleobiologists have long sought to explain how alternative modes of speciation, including budding and bifurcating cladogenesis, shape patterns of evolution. Methods introduced over the past decade have paved the way for a renewed enthusiasm for exploring modes of speciation in the fossil record. However, the field does not yet have a strong intuition for how ancestor-descendant relationships, especially those that arise from budding speciation, might influence the shape of trees reconstructed for fossil or living clades.
View Article and Find Full Text PDFUnderstanding 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.
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