February 8, 2008 | David F. Coppedge

Did Birds Evolve Aeronautical Engineering?

Two news stories on birds may not seem to flock together.  One is about their supreme aeronautical engineering.  The other ponders when they evolved.
    A story on EurekAlert and Science Daily describes how engineers are eyeing birds, bats and insects for design ideas.  The appeal is clear from the following comparisons:

A Blackbird jet flying nearly 2,000 miles per hour covers 32 body lengths per second.  But a common pigeon flying at 50 miles per hour covers 75.  The roll rate of the aerobatic A-4 Skyhawk plane is about 720 degrees per second.  The roll rate of a barn swallow exceeds 5,000 degrees per second.
    Select military aircraft can withstand gravitational forces of 8-10 G.  Many birds routinely experience positive G-forces greater than 10 G and up to 14 G.

It seems audacious, therefore, that humans name their aircraft after birds.  In many ways, a blackbird is top gun over a Blackbird, and a skyhawk rolls circles around a Skyhawk.  No barnstormer could match a barn swallow for daring.  Human aircraft may reach higher speeds and carry heavier masses, but in terms of flight control, they seem stuck at the dodo stage.
    Wei Shyy, an aeronautical engineer, admires animal flyers.  “They’re not only lighter, but also have much more adaptive structures as well as capabilities of integrating aerodynamics with wing and body shapes, which change all the time.” He added, “Natural flyers have outstanding capabilities to remain airborne through wind gusts, rain, and snow.”  That’s why he is studying the possibilities of using flapping wings for aircraft.  Imitating the ability of natural wings to deform quickly might allow pilots to “delay stall, enhance stability and increase thrust.”  The unsteady pace of flapping flight gives the animal the ability to adapt quickly to wind gusts and changing conditions.  The engineer marvelled at a dragonfly’s ability to stay on course in the wind, considering how light it is.  He didn’t even mention that these flyers can all reproduce themselves and use environmentally friendly fuel.
    Meanwhile, in a different thought collective, evolutionary biologists are puzzling over the timing of bird evolution.  Live Science, PhysOrg and Science Daily say that the consensus used to be that modern birds evolved from dinosaurs late in the Cretaceous.  Now, however, researchers at three universities have announced a fight on the date.  Their reanalysis “offers the strongest molecular evidence yet for an ancient origin of modern birds, suggesting that they arose more than 100 million years ago, not 60 million years ago, as fossils suggest.”  In other words, the fossil record and the inferences from molecular evolution have yielded “conflicting results.”  They explained the difference by appealing to the paucity of the fossil record and the realization that the molecular clock is unreliable.  Joseph Brown explained the problem, “different lineages can ‘tick’ at different rates, so applying a single rate to an entire tree could lead to very suspect results.”  This was described as the “rock-clock gap.”

Did the evolutionary fluff give you as much a thrill as the engineering article?  Engineers are forward-thinking scientists.  They use evidence that is observable, testable and repeatable.  They are continuing the practice of the Wright brothers who were inspired by birds over a hundred years ago – and look where that science has led mankind.  We have just seen that even now, after a century of human aeronautical engineering that has taken us from awkward contraptions to the edge of space, our bird, bat and insect neighbors still have wonderful secrets to share.  Isn’t design science of much more value, inspiration and usefulness than a silly story about some lizard that held out its arms 100 million years ago (01/25/2008) and, strictly by chance, mastered pitch, yaw and roll?  Let’s get science back from flights of fancy to a wing and a prayer.

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