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Largest volant bird (Pelagornis) flight performance and other avian papers



Ben Creisler
bcreisler@gmail.com


A new paper that may be of interest:

Daniel T. Ksepka (2014)
Flight performance of the largest volant bird.
Proceedings of the National Academy of Sciences (advance online publication)
doi: 10.1073/pnas.1320297111
http://www.pnas.org/content/early/2014/07/02/1320297111.abstract?sid=1218df99-0769-4df7-abbf-a7e0e2b5f3b5

Significance

A fossil species of pelagornithid bird exhibits the largest known
avian wingspan. Pelagornithids are an extinct group of birds known for
bony tooth-like beak projections, large size, and highly modified wing
bones that raise many questions about their ecology. At 6.4 m, the
wingspan of this species was approximately two times that of the
living Royal Albatross. Modeling of flight parameters in this species
indicates that it was capable of highly efficient gliding and suggests
that pelagornithids exploited a long-range marine soaring strategy
similar, in some ways, to that of extant albatrosses.

Abstract
Pelagornithidae is an extinct clade of birds characterized by bizarre
tooth-like bony projections of the jaws. Here, the flight capabilities
of pelagornithids are explored based on data from a species with the
largest reported wingspan among birds. Pelagornis sandersi sp. nov. is
represented by a skull and substantial postcranial material.
Conservative wingspan estimates (~6.4 m) exceed theoretical maximums
based on extant soaring birds. Modeled flight properties indicate that
lift:drag ratios and glide ratios for P. sandersi were near the upper
limit observed in extant birds and suggest that pelagornithids were
highly efficient gliders, exploiting a long-range soaring ecology.


News stories:

http://news.nationalgeographic.com/news/2014/07/140707-bird-biggest-flight-ancient-wings-charleston-science/


http://phys.org/news/2014-07-world-largest-ever-bird.html
==

Other recent avian papers that may be of interest:

Xia Wang and Julia A. Clarke (2014)
Phylogeny and forelimb disparity in waterbirds.
Evolution (advance online publication)
DOI: 10.1111/evo.12486
http://onlinelibrary.wiley.com/doi/10.1111/evo.12486/abstract


Previous work has shown that the relative proportions of wing
components (i.e., humerus, ulna, carpometacarpus) in birds are related
to function and ecology, but these have rarely been investigated in a
phylogenetic context. Waterbirds including “Pelecaniformes”,
Ciconiiformes, Procellariiformes, Sphenisciformes and Gaviiformes form
a highly supported clade and developed a great diversity of wing forms
and foraging ecologies. In this study, forelimb disparity in the
waterbird clade was assessed in a phylogenetic context. Phylogenetic
signal was assessed via Pagel's lambda, Blomberg's K and permutation
tests. We find that different waterbird clades are clearly separated
based on forelimb component proportions, which are significantly
correlated with phylogeny but not with flight style. Most of the
traditional contents of “Pelecaniformes” (e.g., pelicans, cormorants
and boobies) cluster with Ciconiiformes (herons and storks) and occupy
a reduced morphospace. These taxa are closely related phylogenetically
but exhibit a wide range of ecologies and flight styles.
Procellariiformes (e.g. petrels, albatross, and shearwaters) occupy a
wide range of morphospace, characterized primarily by variation in the
relative length of carpometacarpus and ulna. Gaviiformes (loons)
surprisingly occupy a wing morphospace closest to diving petrels and
penguins. Whether this result may reflect wing proportions
plesiomorphic for the waterbird clade or a functional signal is
unclear. A Bayesian approach detecting significant rate shifts across
phylogeny recovered two such shifts. At the base of the two sister
clades Sphenisciformes + Procellariiformes, a shift to an increase
evolutionary rate of change is inferred for the ulna and
carpometacarpus. Thus, changes in wing shape begin prior to the loss
of flight in the wing-propelled diving clade. Several shifts to slower
rate of change are recovered within stem penguins.

===

Theagarten Lingham-Soliar (2014)
Response to comments by C. Palmer on my paper, Feather structure,
biomechanics and biomimetics: the incredible lightness of being.
Journal of Ornithology (advance online publication)
DOI: 10.1007/s10336-014-1093-1
http://link.springer.com/article/10.1007/s10336-014-1093-1

In the latter part of a paper on feather structure and biomechanics, I
(Lingham-Soliar 2014) critiqued a paper by Nudds and Dyke (2010) on
the inadequacy of feather rachis strength for flapping flight in
Archaeopteryx. Subsequently, I received a few emails from one of the
authors, essentially alleging that I had misrepresented the findings
of Weiss and Kirchner (2010) with respect to the significance of the
foam centre of the rachis. A written response by Palmer (2014)
expressing similar views followed, to which I reply here (for
references not listed see Lingham-Soliar 2014).