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New bird refs

From: Ben Creisler bh480@scn.org
Just in case some recent bird-related refs that may not 
have been mentioned here yet (search didn't indicate 
they'd been discussed in recent postings):

Chiappe, L.M. & G.J. Dyke, 2002. The Mesozoic radiation of 
AB: Until recently, most knowledge of the early history of 
birds and the evolution of their unique specializations 
was based on just a handful of diverse Mesozoic taxa 
widely separated in time and restricted to marine 
environments. Although Archaeopteryx is still the oldest 
and only Jurassic bird, a wealth of recent discoveries 
combined with new phylogenetic analyses have documented 
the divergence of a number of lineages by the beginning of 
the Cretaceous. These and younger Cretaceous fossils have 
filled much of the morphological chasm that existed 
between Archaeopteryx and its living counterparts, 
providing insights into the evolutionary development of 
feathers and other important features of the avian flight 
system. Dramatic new perceptions of the life history, 
growth and development of early birds have also been made 
possible by the latest data. Although no primitive birds 
are known to have survived beyond the end of the 
Cretaceous, the present fossil record provides no evidence 
for a sudden disappearance. Likewise, a Mesozoic origin 
for extant birds remains controversial.

The Auk: Vol. 119 (4). 2002.
Alan Fedducia comments on Prum's paper "Why ornithologists 
should care about the theropod origin of birds": Birds are 
Dinosaurs: Simple Answers to a Complex Problem. pp. 1187-
Storrs Olson reviews New Perspectives on the Origin and 
Early Evolution of Birds. Proceedings of the International 
Symposium in Honor of John H. Ostrom. pp. 1202-1205
[[No real surprises in what they have to say I'm afraid.  
Curiously, Olson referred to Microraptor as a "bird" on 
NPR "All Things Considered" earlier this week (the story 
can be heard on the NPR website).]]

Kimberly S. Bostwick,a and Matthew J. Brady, 2002. 
119 (4):. 943?954. ABSTRACT Most recent research on 
character evolution attempts to identify either (1) 
homology or homoplasy (systematic use of the term 
character), or (2) the adaptive function or selective 
regime underlying the origin of a character 
(?adaptationist? use of the term character). There have 
been relatively few serious considerations or examples of 
neutral character evolution above the molecular level. 
Wing feather taxis in birds, the presence or absence of 
the fifth secondary feather, provides an intriguing 
possible example of nonadaptive character evolution. We 
examine the phylogenetic pattern of wing feather taxis 
among birds to (1) determine its polarity in modern birds 
(Neornithes), (2) hypothesize the frequency and taxonomic 
locations of changes in the taxic state, (3) test whether 
taxis is relatively labile or inert phylogenetically, and 
(4) allow preliminary consideration of whether adaptive or 
selectively neutral processes have produced those 
patterns. Minimum tree length necessary to explain the 
distribution of wing feather taxis was calculated at the 
family level using Sibley and Ahlquist's DNA?DNA 
hybridization tree (1990) . Parsimony analysis indicates 
that the eutaxic condition (fifth secondary present) is 
ancestral in modern birds, and that diastataxy (fifth 
secondary absent) has originated independently at least 7 
times and reversed to the eutaxic condition on at least 13 
occasions within modern birds. Despite multiple 
independent origins and reversals, wing feather taxis is 
extremely conserved throughout the tree, such that one or 
the other state completely characterizes many large 
multiordinal or multifamilial clades. Lack of obvious 
correlations with morphological and ecological traits 
suggest that no single adaptive scenario will explain the 
evolution of wing feather taxis. Instead, the biological 
details and phylogenetic patterns make nonadaptive, or 
selectively neutral evolutionary processes, such as 
genetic drift, an equally if not more plausible 
explanation for the distribution of wing feather taxis. 

Hutchinson. J.R., 2002. The evolution of hindlimb tendons 
and muscles on the line to crown-group birds. COMPARATIVE 
PHYSIOLOGY. DEC 2002; 133 (4) : 1051-1086.
AB: The anatomy and functions of muscle-tendon complexes 
and their bony attachments in birds and their outgroups 
show how the major pelvic limb muscle groups evolved. 
Fossils reveal that most changes evolved after the 
divergence of archosaurs in the Triassic, particularly in 
the dinosaurian precursors to birds. Three-dimensional 
limb control became concentrated at the hip joint; more 
distal joints and muscles were restricted to flexion or 
extension early in dinosaur evolution. Hip extensors 
expanded even though the primary femoral retractor M. 
caudofemoralis longus was reduced. Hip flexors and two- 
joint 'hamstring' muscles were simplified to a few large 
heads. Knee extensors increased their sizes and moment 
arms early in bipedal dinosaurs, but the patella and 
cranial cnemial crest evolved later in birds. Lower limb 
muscles expanded as ossifications such as the hypotarsus 
increased their moment arms. The ossification of lower 
limb tendons, particularly in extensors, is a recent 
novelty of birds. Muscles and tendons that develop large 
forces, stresses, and moments to stabilize or move the 
limbs became increasingly prominent on the line to birds. 
Locomotion evolved in a stepwise pattern that only 
recently produced the derived limb control mechanisms of 
crown-group birds, such as the strongly flexed hip and 
knee joints.