Convergent evolution across the Australian continent: ecotype diversification drives morphological convergence in two distantly related clades of Australian frogs

Convergent evolution can provide insights into the predictability of, and constraints on, the evolution of biodiversity. One striking example of convergence is seen in the ‘river dolphins’. The four dolphin genera that make up the ‘river dolphins’ (Inia geoffrensis, Pontoporia blainvillei, Platanista gangetica and Lipotes vexillifer) do not represent a monophyletic group, despite being very similar in morphology. This has led many to using the ‘river dolphins’ as an example of convergent evolution. However, these morphological similarities have never been quantified. We investigate whether the skulls of the four ‘river dolphin’ genera are convergent when compared to other toothed dolphin taxa. We use geometric morphometrics to uncover shape variation in the skulls of the ‘river dolphins’ and then apply a number of phylogenetic techniques to test for convergence. We find significant convergence in the skull morphology of the ‘river dolphins’. The four genera seem to have experienced evolution in the same direction, leading to a convergent morphotype characterised by elongation of skull features. The cause of this morphological convergence remains unclear, but our results support hypotheses of shared feeding mode or diet and thus provide the foundation for future work into convergence within the Odontoceti.

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Trophic convergence drives morphological convergence in marine tetrapods

Biology Letters ◽

10.1098/rsbl.2014.0709 ◽

2015 ◽

Vol 11 (1) ◽

pp. 20140709 ◽

Cited By ~ 25

Author(s):

Neil P. Kelley ◽

Ryosuke Motani

Keyword(s):

Feeding Ecology ◽

Convergent Evolution ◽

Ecological Niches ◽

Trophic Groups ◽

Functional Constraints ◽

Tooth Morphology ◽

Marine Life ◽

Morphological Convergence ◽

Dietary Data

Marine tetrapod clades (e.g. seals, whales) independently adapted to marine life through the Mesozoic and Caenozoic, and provide iconic examples of convergent evolution. Apparent morphological convergence is often explained as the result of adaptation to similar ecological niches. However, quantitative tests of this hypothesis are uncommon. We use dietary data to classify the feeding ecology of extant marine tetrapods and identify patterns in skull and tooth morphology that discriminate trophic groups across clades. Mapping these patterns onto phylogeny reveals coordinated evolutionary shifts in diet and morphology in different marine tetrapod lineages. Similarities in morphology between species with similar diets—even across large phylogenetic distances—are consistent with previous hypotheses that shared functional constraints drive convergent evolution in marine tetrapods.

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Convergent evolution in the Euarchontoglires

Biology Letters ◽

10.1098/rsbl.2018.0366 ◽

2018 ◽

Vol 14 (8) ◽

pp. 20180366 ◽

Cited By ~ 4

Author(s):

Philip J. R. Morris ◽

Samuel N. F. Cobb ◽

Philip G. Cox

Keyword(s):

Quantitative Analysis ◽

Convergent Evolution ◽

Three Dimensional ◽

Classic Case ◽

Independent Evolution ◽

Morphological Convergence ◽

Daubentonia Madagascariensis ◽

Degree Of Convergence ◽

Wood Boring

Convergence—the independent evolution of similar phenotypes in distantly related clades—is a widespread and much-studied phenomenon. An often-cited, but hitherto untested, case of morphological convergence is that between the aye-aye and squirrels. The aye-aye ( Daubentonia madagascariensis ) is a highly unusual lemuriform primate that has evolved a dentition similar to that of rodents: it possesses large, ever-growing incisors which it uses to strip the bark from trees in order to feed on wood-boring beetle larvae. Indeed, such is the similarity that some of the earliest classifications of the aye-aye placed it in the squirrel genus Sciurus . Here, we aimed to test the degree of convergence between the skulls and lower jaws of squirrels and the aye-aye. Three-dimensional landmarks were recorded from the crania and mandibles of 46 taxa representing the majority of families in the Euarchontoglires. Results were plotted as phylomorphospaces and convergence measures were calculated. The convergence between squirrels and the aye-aye was shown to be statistically significant for both the cranium and mandible, although the mandibles seem to converge more closely in shape. The convergence may indicate strong functional drivers of morphology in these taxa, i.e. the use of the incisors to produce high bite forces during feeding. Overall, we have shown that this classic case of convergence stands up to quantitative analysis.

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Morphological convergence in ‘river dolphin’ skulls: a disparate grouping justified

10.7287/peerj.preprints.3222v1 ◽

2017 ◽

Author(s):

Charlotte E Page ◽

Natalie Cooper

Keyword(s):

Geometric Morphometrics ◽

Convergent Evolution ◽

Shape Variation ◽

Skull Morphology ◽

Feeding Mode ◽

River Dolphin ◽

Morphological Convergence ◽

Inia Geoffrensis ◽

Pontoporia Blainvillei ◽

Future Work

Convergent evolution can provide insights into the predictability of, and constraints on, the evolution of biodiversity. One striking example of convergence is seen in the ‘river dolphins’. The four dolphin genera that make up the ‘river dolphins’ (Inia geoffrensis, Pontoporia blainvillei, Platanista gangetica and Lipotes vexillifer) do not represent a monophyletic group, despite being very similar in morphology. This has led many to using the ‘river dolphins’ as an example of convergent evolution. However, these morphological similarities have never been quantified. We investigate whether the skulls of the four ‘river dolphin’ genera are convergent when compared to other toothed dolphin taxa. We use geometric morphometrics to uncover shape variation in the skulls of the ‘river dolphins’ and then apply a number of phylogenetic techniques to test for convergence. We find significant convergence in the skull morphology of the ‘river dolphins’. The four genera seem to have experienced evolution in the same direction, leading to a convergent morphotype characterised by elongation of skull features. The cause of this morphological convergence remains unclear, but our results support hypotheses of shared feeding mode or diet and thus provide the foundation for future work into convergence within the Odontoceti.

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Morphological convergence obscures functional diversity in sabre-toothed carnivores

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.1818 ◽

2020 ◽

Vol 287 (1935) ◽

pp. 20201818

Author(s):

Stephan Lautenschlager ◽

Borja Figueirido ◽

Daniel D. Cashmore ◽

Eva-Maria Bendel ◽

Thomas L. Stubbs

Keyword(s):

Functional Diversity ◽

Convergent Evolution ◽

Bending Strength ◽

Functional Performance ◽

Niche Partitioning ◽

Bite Force ◽

Evolutionary Rates ◽

Morphological Convergence ◽

Prey Killing ◽

Evolutionary Paths

The acquisition of elongated, sabre-like canines in multiple vertebrate clades during the last 265 Myr represents a remarkable example for convergent evolution. Due to striking superficial similarities in the cranial skeleton, the same or similar skull and jaw functions have been inferred for sabre-toothed species and interpreted as an adaptation to subdue large-bodied prey. However, although some sabre-tooth lineages have been classified into different ecomorphs (dirk-tooths and scimitar-tooths) the functional diversity within and between groups and the evolutionary paths leading to these specializations are unknown. Here, we use a suite of biomechanical simulations to analyse key functional parameters (mandibular gape angle, bending strength, bite force) to compare the functional performance of different groups and to quantify evolutionary rates across sabre-tooth vertebrates. Our results demonstrate a remarkably high functional diversity between sabre-tooth lineages and that different cranial function and prey killing strategies evolved within clades. Moreover, different biomechanical adaptations in coexisting sabre-tooth species further suggest that this functional diversity was at least partially driven by niche partitioning.

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Morphological convergence in ‘river dolphin’ skulls

PeerJ ◽

10.7717/peerj.4090 ◽

2017 ◽

Vol 5 ◽

pp. e4090 ◽

Cited By ~ 8

Author(s):

Charlotte E. Page ◽

Natalie Cooper

Keyword(s):

Geometric Morphometrics ◽

Convergent Evolution ◽

Shape Variation ◽

Skull Morphology ◽

Feeding Mode ◽

River Dolphin ◽

Morphological Convergence ◽

Inia Geoffrensis ◽

Pontoporia Blainvillei ◽

Future Work

Convergent evolution can provide insights into the predictability of, and constraints on, the evolution of biodiversity. One striking example of convergence is seen in the ‘river dolphins’. The four dolphin genera that make up the ‘river dolphins’ (Inia geoffrensis, Pontoporia blainvillei, Platanista gangetica and Lipotes vexillifer) do not represent a single monophyletic group, despite being very similar in morphology. This has led many to using the ‘river dolphins’ as an example of convergent evolution. We investigate whether the skulls of the four ‘river dolphin’ genera are convergent when compared to other toothed dolphin taxa in addition to identifying convergent cranial and mandibular features. We use geometric morphometrics to uncover shape variation in the skulls of the ‘river dolphins’ and then apply a number of phylogenetic techniques to test for convergence. We find significant convergence in the skull morphology of the ‘river dolphins’. The four genera seem to have evolved similar skull shapes, leading to a convergent morphotype characterised by elongation of skull features. The cause of this morphological convergence remains unclear. However, the features we uncover as convergent, in particular elongation of the rostrum, support hypotheses of shared feeding mode or diet and thus provide the foundation for future work into convergence within the Odontoceti.

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