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. 2010 Feb 7;277(1680):383-9.
doi: 10.1098/rspb.2009.1603. Epub 2009 Oct 14.

Evidence for modular evolution in a long-tailed pterosaur with a pterodactyloid skull

Junchang Lü  1 , David M Unwin, Xingsheng Jin, Yongqing Liu, Qiang Ji
Affiliations

Evidence for modular evolution in a long-tailed pterosaur with a pterodactyloid skull

Junchang Lü et al. Proc Biol Sci. .

Abstract

The fossil record is a unique source of evidence for important evolutionary phenomena such as transitions between major clades. Frustratingly, relevant fossils are still comparatively rare, most transitions have yet to be documented in detail and the mechanisms that underpin such events, typified by rapid large scale changes and for which microevolutionary processes seem insufficient, are still unclear. A new pterosaur (Mesozoic flying reptile) from the Middle Jurassic of China, Darwinopterus modularis gen. et sp. nov., provides the first insights into a prominent, but poorly understood transition between basal, predominantly long-tailed pterosaurs and the more derived, exclusively short-tailed pterodactyloids. Darwinopterus exhibits a remarkable 'modular' combination of characters: the skull and neck are typically pterodactyloid, exhibiting numerous derived character states, while the remainder of the skeleton is almost completely plesiomorphic and identical to that of basal pterosaurs. This pattern supports the idea that modules, tightly integrated complexes of characters with discrete, semi-independent and temporally persistent histories, were the principal focus of natural selection and played a leading role in evolutionary transitions.

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Figures

Figure 1.
Figure 1.
Preserved skeletal remains of the holotype of D. modularis gen. et sp. nov. (ZMNH M8782).
Figure 2.
Figure 2.
Holotype ZMNH M8782 (a,b,e) and referred specimen YH-2000 (f) of D. modularis gen. et sp. nov.: (a) cranium and mandibles in the right lateral view, cervicals 1–4 in the dorsal view, scale bar 5 cm; (b) details of the dentition in the anterior tip of the rostrum, scale bar 2 cm; (c) restoration of the skull, scale bar 5 cm; (d) restoration of the right pes in the anterior view, scale bar 2 cm; (e) details of the seventh to ninth caudal vertebrae and bony rods that enclose them, scale bar 0.5 cm; (f) complete skeleton seen in the ventral aspect, except for skull which is in the right lateral view, scale bar 5 cm. Abbreviations: a, articular; cr, cranial crest; d, dentary; f, frontal; j, jugal; l, lacrimal; ldt, lateral distal tarsal; m, maxilla; mdt, medial distal tarsal; met, metatarsal; n, nasal; naof, nasoantorbital fenestra; p, parietal; pd, pedal digit; pf, prefrontal; pm, premaxilla; po, postorbital; q, quadrate; qj, quadratojugal; sq, squamosal; ti, tibia.
Figure 3.
Figure 3.
Comparison of D. modularis gen. et. sp. nov. to other pterosaurs: (a) skull as a proportion of body length (DSV) plotted against a proxy for size (length of the humerus in mm); (b) relative length of the neck; (c) relative length of metacarpus. Filled circles, basal forms; crosses, pterodactyloids; stars, Darwinopterus.
Figure 4.
Figure 4.
Phylogenetic relationships and evolutionary context of Darwinopterus. (a) Phylogenetic analysis of Pterosauria (see the electronic supplementary material for details), possible alternative locations for Darwinopterus indicated by D1 and D2. (b) Schematic restorations of a basal pterosaur (above), Darwinopterus (middle) and a pterodactyloid (below) standardized to the length of the DSV, the arrow indicates direction of evolutionary transformations; modules: skull (red), neck (yellow), body and limbs (monochrome), tail (blue); I, transition phase one; II, transition phase two. (c) Time-calibrated phylogeny showing the temporal range of the main pterosaur clades; basal clades in red, pterodactyloids in blue; known ranges of clades indicated by solid bar, inferred ‘ghost’ range by coloured line; footprint symbols indicate approximate age of principal pterosaur track sites based on Lockley et al. (2008); stratigraphic units and age in millions of years based on Gradstein et al. (2005). 1, Preondactylus; 2, Dimorphodontidae; 3, Anurognathidae; 4, Campylognathoididae; 5, Scaphognathinae; 6, Rhamphorhynchinae; 7, Darwinopterus; 8, Boreopterus; 9, Istiodactylidae; 10, Ornithocheiridae; 11, Pteranodon; 12, Nyctosauridae; 13, Pterodactylus; 14, Cycnorhamphus; 15, Ctenochasmatinae; 16, Gnathosaurinae; 17, Germanodactylus; 18, Dsungaripteridae; 19, Lonchodectes; 20, Tapejaridae; 21, Chaoyangopteridae; 22, Thalassodromidae; 23, Azhdarchidae. Abbreviations: M, Monofenestrata; P, Pterodactyloidea; T, Pterosauria; ca, caudal vertebral series; cv, cervical vertebral series; mc, metacarpus; na, nasoantorbital fenestra; r, rib; sk, skull; v, fifth pedal digit.
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References

    1. Andres B., Ji Q.2008A new pterosaur from the Liaoning Province of China, the phylogeny of Pterodactyloidea, and convergence in their cervical vertebrae. Palaeontology 51, 453–469 (doi:10.1111/j.1475-4983.2008.00761.x) - DOI
    1. Barrett P. M., Butler R. J., Edwards N. P., Milner A. R.2008Pterosaur distribution in time and space: an atlas. Zitteliana B 28, 61–107
    1. Bennett S. C.1996Year classes of pterosaurs from the Solnhofen Limestone of Germany: taxonomic and systematic implications. J. Vertebr. Paleontol. 16, 432–444
    1. Bennett S. C.2001The osteology and functional morphology of the Late Cretaceous pterosaur Pteranodon. Palaeontographica Abt. A 260, 1–153
    1. Bennett S. C.2007A second specimen of the pterosaur Anurognathus ammoni. Pal. Z. 81, 376–398

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