| 1. |
- Liu, Xiaokang, et al.
(författare)
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Heterogeneous selectivity and morphological evolution of marine clades during the Permian-Triassic mass extinction
- 2024
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Ingår i: NATURE ECOLOGY & EVOLUTION. - 2397-334X. ; 8:1248–1258
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Tidskriftsartikel (refereegranskat)abstract
- Morphological disparity and taxonomic diversity are distinct measures of biodiversity, typically expected to evolve synergistically. However, evidence from mass extinctions indicates that they can be decoupled, and while mass extinctions lead to a drastic loss of diversity, their impact on disparity remains unclear. Here we evaluate the dynamics of morphological disparity and extinction selectivity across the Permian-Triassic mass extinction. We developed an automated approach, termed DeepMorph, for the extraction of morphological features from fossil images using a deep learning model and applied it to a high-resolution temporal dataset encompassing 599 genera across six marine clades. Ammonoids, brachiopods and ostracods experienced a selective loss of complex and ornamented forms, while bivalves, gastropods and conodonts did not experience morphologically selective extinctions. The presence and intensity of morphological selectivity probably reflect the variations in environmental tolerance thresholds among different clades. In clades affected by selective extinctions, the intensity of diversity loss promoted the loss of morphological disparity. Conversely, under non-selective extinctions, the magnitude of diversity loss had a negligible impact on disparity. Our results highlight that the Permian-Triassic mass extinction had heterogeneous morphological selective impacts across clades, offering new insights into how mass extinctions can reshape biodiversity and ecosystem structure. Using a deep learning method that extracts morphological features from images of marine fossils, the authors explore morphological disparity dynamics over a time series of 4 million years, spanning the Permian-Triassic mass extinction event.
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| 2. |
- Pimiento, C., et al.
(författare)
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The Pliocene marine megafauna extinction and its impact on functional diversity
- 2017
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Ingår i: Nature Ecology & Evolution. - : Springer Science and Business Media LLC. - 2397-334X. ; 1:8, s. 1100-1106
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Tidskriftsartikel (refereegranskat)abstract
- The end of the Pliocene marked the beginning of a period of great climatic variability and sea-level oscillations. Here, based on a new analysis of the fossil record, we identify a previously unrecognized extinction event among marine megafauna (mammals, seabirds, turtles and sharks) during this time, with extinction rates three times higher than in the rest of the Cenozoic, and with 36% of Pliocene genera failing to survive into the Pleistocene. To gauge the potential consequences of this event for ecosystem functioning, we evaluate its impacts on functional diversity, focusing on the 86% of the megafauna genera that are associated with coastal habitats. Seven (14%) coastal functional entities (unique trait combinations) disappeared, along with 17% of functional richness (volume of the functional space). The origination of new genera during the Pleistocene created new functional entities and contributed to a functional shift of 21%, but minimally compensated for the functional space lost. Reconstructions show that from the late Pliocene onwards, the global area of the neritic zone significantly diminished and exhibited amplified fluctuations. We hypothesize that the abrupt loss of productive coastal habitats, potentially acting alongside oceanographic alterations, was a key extinction driver. The importance of area loss is supported by model analyses showing that animals with high energy requirements (homeotherms) were more susceptible to extinction. The extinction event we uncover here demonstrates that marine megafauna were more vulnerable to global environmental changes in the recent geological past than previously thought.
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| 3. |
- Rolland, J., et al.
(författare)
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Conceptual and empirical bridges between micro- and macroevolution
- 2023
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Ingår i: Nature Ecology and Evolution. - 2397-334X. ; 7, s. 1181-1193
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Tidskriftsartikel (refereegranskat)abstract
- This Perspective discusses four questions of evolutionary biology that bridge macro and microevolution perspectives and proposes future research avenues to link evolutionary mechanisms and processes. Explaining broad molecular, phenotypic and species biodiversity patterns necessitates a unifying framework spanning multiple evolutionary scales. Here we argue that although substantial effort has been made to reconcile microevolution and macroevolution, much work remains to identify the links between biological processes at play. We highlight four major questions of evolutionary biology whose solutions require conceptual bridges between micro and macroevolution. We review potential avenues for future research to establish how mechanisms at one scale (drift, mutation, migration, selection) translate to processes at the other scale (speciation, extinction, biogeographic dispersal) and vice versa. We propose ways in which current comparative methods to infer molecular evolution, phenotypic evolution and species diversification could be improved to specifically address these questions. We conclude that researchers are in a better position than ever before to build a synthesis to understand how microevolutionary dynamics unfold over millions of years.
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| 4. |
- Rolland, J., et al.
(författare)
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The impact of endothermy on the climatic niche evolution and the distribution of vertebrate diversity
- 2018
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Ingår i: Nature Ecology & Evolution. - : Springer Science and Business Media LLC. - 2397-334X. ; 2:3, s. 459-464
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the mechanisms by which the abiotic and biotic requirements of species, or ecological niches, change over time is a central issue in evolutionary biology. Niche evolution is poorly understood at both the macroecological and macroevolutionary scales, as niches can shift over short periods of time but appear to change more slowly over longer timescales. Although reconstructing past niches has always been a major concern for palaeontologists and evolutionary biologists, only a few recent studies have successfully determined the factors that affect niche evolution. Here, we compare the evolution of climatic niches in four main groups of terrestrial vertebrates using a modelling approach integrating both palaeontological and neontological data, and large-scale datasets that contain information on the current distributions, phylogenetic relationships and fossil records for a total of 11,465 species. By reconstructing historical shifts in geographical ranges and climatic niches, we show that niche shifts are significantly faster in endotherms (birds and mammals) than in ectotherms (squamates and amphibians). We further demonstrate that the diversity patterns of the four clades are directly affected by the rate of niche evolution, with fewer latitudinal shifts in ectotherms.
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| 5. |
- Silvestro, Daniele, et al.
(författare)
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Fossil data support a pre-Cretaceous origin of flowering plants
- 2021
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Ingår i: Nature Ecology & Evolution. - : Springer Science and Business Media LLC. - 2397-334X. ; 5, s. 449-457
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Tidskriftsartikel (refereegranskat)abstract
- Flowering plants (angiosperms) are the most diverse of all land plants, becoming abundant in the Cretaceous and achieving dominance in the Cenozoic. However, the exact timing of their origin remains a controversial topic, with molecular clocks generally placing their origin much further back in time than the oldest unequivocal fossils. To resolve this discrepancy, we developed a Bayesian method to estimate the ages of angiosperm families on the basis of the fossil record (a newly compiled dataset of similar to 15,000 occurrences in 198 families) and their living diversity. Our results indicate that several families originated in the Jurassic, strongly rejecting a Cretaceous origin for the group. We report a marked increase in lineage accumulation from 125 to 72 million years ago, supporting Darwin's hypothesis of a rapid Cretaceous angiosperm diversification. Our results demonstrate that a pre-Cretaceous origin of angiosperms is supported not only by molecular clock approaches but also by analyses of the fossil record that explicitly correct for incomplete sampling.
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