Eggshell structure in the Shoebill and pelecaniform birds: comparison with Hamerkop, herons, ibises, and storks

2005

J Zoological System

Plotopterids (Aves: Plotopteridae) are extinct wing-propelled diving birds which exhibit a strikingly similar wing morphology to penguins (Spheniscidae), but also share derived characters with ÔpelecaniformÕ birds that are absent in penguins. The similarities between Plotopteridae and Spheniscidae have hitherto been attributed to convergence, and plotopterids were considered to be most closely related to the ÔpelecaniformÕ Phalacrocoracidae (cormorants) and Anhingidae (anhingas). However, here I show that assignment of plotopterids to ÔpelecaniformÕ birds does not necessarily preclude them from being the sister taxon of penguins. Cladistic analysis of 68 morphological characters resulted in sister group relationship between Plotopteridae and Spheniscidae, and the clade (Plotopteridae + Spheniscidae) was shown to be the sister taxon of the Suloidea, i.e. a clade including Sulidae (boobies and gannets), Phalacrocoracidae, and Anhingidae. Derived characters are discussed which support this novel hypothesis. Paedomorphosis probably accounts for the absence of derived characters in penguins that are shared by Plotopteridae and members of the Steganopodes. Plotopterids exemplify the importance of fossil birds for analyzing the phylogenetic relationships of modern taxa that exhibit a highly apomorphic morphology.

“…1. In Podicipedidae and Phoenicopteridae the eggshell is covered with a layer of amorphous calcium phosphate (Mikhailov 1995).…”

Section: Results Of Phylogenetic Analysismentioning

confidence: 99%

Section: Characters Supporting Inclusion Of Spheniscidae Into the ‘Pementioning

confidence: 99%

Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae)

2005

J Zoological System

“…(69) Eggs covered with a chalky layer of amorphous calcium phosphate (CI = 1.0). This character otherwise occurs only in some galliform birds (Megapodiidae, Mikhailov, 1995). The eggs of few other taxa (Balaenicipitidae, Scopidae, many Pelecaniformes, Spheniscidae and some Cuculidae) are covered with a layer of amorphous calcium carbonate (Mikhailov, 1995).…”

Section: Resultsmentioning

confidence: 99%

Morphological evidence for sister group relationship between flamingos (Aves: Phoenicopteridae) and grebes (Podicipedidae)

Zoological Journal of the Linnean Society

2004

107

A recent molecular analysis strongly supported sister group relationship between flamingos (Phoenicopteridae) and grebes (Podicipedidae), a hypothesis which has not been suggested before. Flamingos are long-legged filter-feeders whereas grebes are morphologically quite divergent foot-propelled diving birds, and sister group relationship between these two taxa would thus provide an interesting example of evolution of different feeding strategies in birds. To test monophyly of a clade including grebes and flamingos, I performed a cladistic analysis of 70 morphological characters which were scored for 17 taxa. Parsimony analysis of these data supported monophyly of the taxon (Podicipedidae + Phoenicopteridae) and the clade received high bootstrap support. Previously overlooked morphological, oological and parasitological evidence is recorded which supports this hypothesis, and which makes the taxon (Podicipedidae + Phoenicopteridae) one of the best supported higher-level clades within modern birds. The phylogenetic significance of some fossil flamingo-like birds is discussed. The Middle Eocene taxon Juncitarsus is most likely the sister taxon of the clade (Podicipedidae + (Palaelodidae + Phoenicopteridae)) although resolution of its exact systematic position awaits revision of the fossil material. Contrary to previous assumptions, it is more parsimonious to assume that flamingos evolved from a highly aquatic ancestor than from a shorebird-like ancestor.

“…Eggshell covered with layer of microglobular material (amorphous form of calcium carbonate): no (0), yes (1) (Mikhailov 1995).…”

Section: Eggs Incubated Beneath Feet: No (0) Yesmentioning

confidence: 99%

Die phylogenetischen Beziehungen des Schuhschnabels (Balaeniceps rex)

2003

J Ornithol

SummaryThe phylogenetic affinities between the shoebill (Balaenicipitidae) and pelecaniform and ciconiiform birds are analysed. A cladistic analysis of 54 anatomical characters resulted in monophyly of the taxon (Scopidae + (Balaenicipitidae + Steganopodes (sensu Cracraft 1985))) and showed both Ciconiiformes and Pelecaniformes to be polyphyletic. Derived characters which support the resulting phylogeny are discussed. Monophyly of the taxon (Scopidae + (Balaenicipitidae + Steganopodes)) is better supported by morphological evidence than monophyly of the taxon (Procellariiformes + (Phaethontidae + Steganopodes)) which was established by Cracrafl (1985). The shared derived characters of Scopidae, Balaenicipitidae and Steganopodes are furthermore less easily explained by convergent evolution than by the few characters which support monophyly of the taxon (Phaethontidae + Steganopodes). The Phaethontidae share derived characters with the Procellariiformes, which might support a sister group relationship between the two taxa.Keywords: Phylogeny, Balaenicipitidae, Scopidae, Pelecanifonnes, Ciconiiformes, Procellariiformes, osteology. Zusammenfassung Die phylogenetischen Beziehungen des Schuhschnabels (Balaeniceps rex)Die phylogenetischen Beziehungen zwischen dem Schuhschnabel (Balaenicipitidae) und pelecaniformen und ciconiiformen V6geln werden untersucht. Eine kladistische Analyse yon 54 anatomischen Merkmalen resultierte in Monophylie des Taxons (Scopidae + (Balaenicipitidae + Steganopodes (sensu Cracraft 1985))) und ergab, dass sowohl Ciconiiformes als auch Pelecaniformes polyphyletisch sind. Abgeleitete Merkmale, welche den resultierenden Stammbaum begrtinden, werden diskutiert. Monophylie des Taxons (Scopidae + (Balaenicipitidae + Steganopodes)) ist besser gesttitzt durch morphologische Merkmale, als die yon Cracraft (1985) begrtindete Monophylie des Taxons (Procellariiforrues + (Phaethontidae + Steganopodes)). Die gemeinsamen abgeleiteten Merkmale von Scopidae, Balaenicipitidae und Steganopodes lassen sich dartiber hinaus weniger leicht dutch Konvergenz erkl~en, als die wenigen Merkmale, welche Monophylie des Taxons (Phaethontidae + Steganopodes) begrtinden k6nnten. Die Phaethontidae teilen abgeleitete Merkmale mit den Procellariiformes, welche eine Schwestergmppenbeziehung zwischen beiden Taxa sttitzen k6nnten.U.S.