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Apologies if these have been mentioned on this list...
Pike, A.V.L., Maitland, D.P. (2004). Scaling of bird claws. Journal of
Zoology (London). 262(1): 73-81
ABSTRACT: The claw geometry of birds can be used to predict their mode of
life. Previous studies, however, have not considered how bird size might
affect these predictions. Thus, in the present study, the geometric scaling
relationships of bird claws are examined for a variety of extant birds with
different modes of life: predatory, climbing, perching or ground-dwelling.
Measurements of hind-limb claw radius (i.e. claw size) and claw angle (i.e.
claw 'hookedness') of the third digit claw were made on 120 species of bird
ranging from 0.0057 kg to 44 kg in body mass. Claw radius was found to be
proportional to (body mass)0.34 across all species. Claw angle was found to
increase with body mass for predatory and climbing birds (i.e. bigger birds
have relatively more hooked claws), and decrease with body mass for
ground-dwelling birds (i.e. bigger birds have relatively less hooked or
flatter claws). No significant relationship was found between claw angle and
body mass for perching birds. Mode of life could not be predicted with any
certainty using measurements of either claw radius or claw angle, suggesting
difficulty in assigning fossil species such as Archaeopteryx to a specific
locomotor category. As claw design should enable the claw to withstand the
forces placed upon it, further work is needed to establish the stresses
experienced by the claws of different types of bird.
Nudds, R.L., Dyke, G.J., Rayner, J.M.V. (2004). Forelimb proportions and
the evolutionary radiation of neornithes. Proceedings of the Royal Society
Biological Sciences Series B. 271 (Suppl. 5): S324-S327.
ABSTRACT: Analysis of a comprehensive dataset demonstrates that the brachial
index (BI=humerus length/ulna length) of modern birds (Neornithes) varies
significantly between clades at all taxonomic levels, yet is strongly
correlated with recent phylogenetic hypotheses. Variance in BI at the
infraclass level is low, but increases rapidly during the proposed major
radiation of neornithines in the Palaeocene and Eocene. Although a BI of
greater than 1 is primitive for Neornithes, more basal groups of Mesozoic
birds (Confuciusornithidae and some members of the diverse Enantiornithidae)
had BIs comparable with those of 'higher' modern clades. It is possible that
occupation of ecological niches by these Mesozoic clades precluded the
divergence of some groups of neornithines until after the
Cretaceous-Tertiary boundary. We suggest that with further analysis and data
collection the relationships between flight behaviour, ecology and BI can be
determined. Hence, BI may provide a useful tool for characterizing the
ecology of fossil birds.
On a completely different subject, Dann Pigdon wrote:
As for cattle: Australian cattle stations are huge (some of them are
larger than small European countries),
Not a huge feat, per se. You don't have to be huge to be larger than Monaco
or San Marino, or even Liechtenstein. ;-)
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