New Avenues for Old Travellers: Phenotypic Evolutionary Trends Meet Morphodynamics, and Both Enter the Global Change Biology Era

Abstract Evolutionary trends (ETs) are traditionally defined as substantial changes in the state of traits through time produced by a persistent condition directional evolution. ETs might also include responses to ecological, climatic or biological gradients and represent primary evolutionary pattern at high taxonomic levels over long-time scales. The absence well-supported operative definition blurred conceptual differences between other key concepts evolution such convergence, parallel evolution, divergence. Also, it prevented formulation modern guidelines for studying dynamics related them. In phenotypic theory morphodynamics states that interplay factors phylogeny, evo-devo constraints, environment, function determines morphological After introducing new definition, here we provide morphodynamics-based framework ETs, discussing how understanding impact these on improves explanation links patterns processes underpinning We envisage adopting quantitative, pattern-based, multifactorial approach will pave way potential applications this field biology. framework, exploiting catalysing effect climate change research induced global an ideal arena validating hypotheses about predictability