Rubbish flyers

R. L. Nudds, G. J. Dyke. Narrow Primary Feather Rachises in Confuciusornis and Archaeopteryx Suggest Poor Flight Ability. Science, 2010; 328

The fossil birds Archaeopteryx and Confuciusornis had feathered wings resembling those of living birds, but their flight capabilities remain uncertain. Analysis of the rachises of their primary feathers shows that the rachises were much thinner and weaker than those of modern birds, and thus the birds were not capable of flight. Only if the primary feather rachises were solid in cross-section (the strongest structural configuration), and not hollow as in living birds, would flight have been possible. Hence, if Archaeopteryx and Confuciusornis were flapping flyers, they must have had a feather structure that was fundamentally different from that of living birds. Alternatively, if they were only gliders, then the flapping wing stroke must have appeared after the divergence of Confuciusornis, likely within the enantiornithine or ornithurine radiations.

Or, as ScienceDaily summarized: The evolution of flight took longer than previously thought with the ancestors of modern birds "rubbish" at flying, if they flew at all, according to scientists.

Competition Drives Big Beaks Out of Business

The Darwin's Finch story I briefly mentioned is a fascinating part of a long term study by husband and wife team Peter and Rosemary Grant. They now have an amazing 37 year data set on these small birds on the Galapagos.

One of the latest parts of the story to be revealed was published in Science in 2006 as Evolution of Character Displacement in Darwin's Finches. It's also included in their news summary as Competition Drives Big Beaks Out of Business.

I think the fascinating part of this story is that it is the interaction of environment and competitors that drives evolution. Whilst resources are plentiful competition is weak but during the drought the effects of competition became severe.

Here we report that a Darwin's finch species (Geospiza fortis) on an undisturbed Galápagos island diverged in beak size from a competitor species (G. magnirostris) 22 years after the competitor's arrival, when they jointly and severely depleted the food supply. The observed evolutionary response to natural selection was the strongest recorded in 33 years of study, and close to the value predicted from the high heritability of beak size. These findings support the role of competition in models of community assembly, speciation, and adaptive radiations.

You'll believe a penguin can fly

I've posted this before but I'm posting it again for two reasons. 1) You get to see penguin's 'flying' 2) the combination of soundtrack and video is truly strange. Penguin's - adorable flightless comedians of the Antarctic. Leonard Cohen - the adorable flightless poet from Canada. Put them together and you get something truly disturbing.

Bird identification

When we visited CCBER I mentioned museums being put to uses that are only limited by your imagination. I'm sure the original curators of the Smithsonian would never have imagined that their prized bird collections would one day be used to identify fragments of bird that had passed through a jet engine (particularly since many of the collections probably predate the jet engine).

But today the Smithsonian houses the 'Feather Identification Lab' where a staff of four analyze the remains of over 4,000 bird-plane collisions a year. The New York Times had a nice article on the lab: Identifying the Bird, When Not Much Bird Is Left.

Although you might think that these days it could all be done by DNA analysis instead of experts looking at feathers the article illustrates that DNA analysis will only take you so far. In one recent case the DNA from a bird strike at 1,500 feet came back as a deer. It required a human expert to identify the feather as coming from a black vulture - explaining the presence of deer DNA in the engine.