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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
birds. ANNUAL REVIEW OF ECOLOGY AND SYSTEMATICS.33 : 91-
124.
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-
1201.
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.
PHYLOGENETIC ANALYSIS OF WING FEATHER TAXIS IN BIRDS:
MACROEVOLUTIONARY PATTERNS OF GENETIC DRIFT? The Auk: Vol.
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
BIOCHEMISTRY AND PHYSIOLOGY A MOLECULAR AND INTEGRATIVE
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.