Hovering in midair

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F-35 fighter aircraft have been designed to meet requirements of three different US military branches. Australia plans to purchase the F-35A air force version for the RAAF, the navy F-35C is modified for use on aircraft carriers and the marine F-35B has the ability to hover and land vertically. It turns out that engineering F-35s to hover has not been simple. In fact, some blame the engineering challenges of the F-35B for many of the issues that have cropped up in F-35 development. Hovering is a lot harder than you would think.

Interestingly, hovering flight is no less challenging when it comes to birds. Just as the F-35B looks much like other fighter aircraft, particularly its F-35A and F-35C siblings, hummingbirds look much like other birds in that they have two wings, a tail, feathers, a beak and so on. But underneath their skin and its covering of jewel-coloured feathers, they are dramatically engineered to allow them to hover and even fly backwards; something other birds are incapable of.

Adaptations that allow hummingbirds to hover or fly backwards would normally be explained as a product of design . . .

Like irreducibly complex molecular systems, the package of adaptations that allow hummingbirds exceptional flying abilities challenges Darwinism, particularly if the Darwinian requirement that each incremental change somehow increases the fitness of the intermediates is kept in mind. Uniquely among vertebrates, hummingbirds use their wings in a way similar to hovering insects such as bees. In hummingbirds a large portion of the wing is composed of fused wrist and hand bones. The shoulder joint is modified to allow the usual up and down motion of a wing as well as a greater degree of twisting. This appears to be a large part of the secret to hummingbirds’ insect-like flight in which both up and down strokes of the wing provide lift. A modified wing and shoulder combined with pectoral muscles composed almost exclusively of type 1 fibres, which allow prolonged exertion (typically at the expense of speed in other organisms, but apparently not in hummingbirds), a reconfiguration of tendon attachment that allows very short muscle contractions to move the wing through its entire stroke, a brain to coordinate the necessary complex movements and numerous other adaptations and presto, hummingbirds can buzz through the air like bumblebees.

Adaptations that allow hummingbirds to hover or fly backwards would normally be explained as a product of design, just as the lift fan, swivelling exhaust and other engineering modifications for hovering flight on F-35Bs are. For philosophical reasons, materialistic Darwinism rejects this explanation. Is there other evidence of bird evolution that might support the assertion that hummingbird adaptations to their particular lifestyle evolved gradually via “numerous, successive, slight modifications?” Not really. In fact, without trying to make too much of absent evidence (which is not evidence of absence), the evidence we have points in the opposite direction. Fossil hummingbirds, which are not common, are universally fully formed with the adaptations already in place that we associate with hummingbirds’ unique flying ability among vertebrates. This is why the few fossils that are available can be unambiguously identified as hummingbirds. The best candidate for a missing link is probably Eocypselus rowei, thought to be intermediate between swifts and hummingbirds. However, the discoverers point out that E. rowei “shows neither modifications for the continuous gliding used by swifts nor modifications for the hovering flight style used by hummingbirds”.2 

Like F-35 fighters, if we want to see hummingbirds in Australia, we will need to import them from the Americas, but this does not prevent us from marvelling at the beauty and design in our own birds. Even as children we understood that “Mr Nobody” is not a reasonable explanation for breakage of a living room lamp during a rough and tumble indoor football match. Why accept “Mr Nobody” as the explanation of where hummingbirds, or any other birds, came from? Generally, rational people reject imaginary things because experience shows us that it is real causes in the real world that actually account for everything from aircraft to broken lamps. The Bible introduces us to Jesus Christ, that Real Cause, the Creator God who not only notes when a sparrow falls (Matthew 10:29), but also created and sustains “all things” (Revelation 4:11) including hummingbirds and us.
 

Tim Standish visits the Record InFocus set to discuss his Flight: The genius of birds documentary.


1. Charles Darwin made this a requirement of his theory of evolution: Darwin, C. R. 1859. On the origin of species by means of natural selection. London: John Murray. 1st edition, 1st issue. P 189.

2. Ksepka DT. Clarke JA. Nesbitt SJ. Kulp FB. Grande L. 2013. Fossil evidence of wing shape in a stem relative of swifts and hummingbirds (Aves, Pan-Apodiformes). Proceedings of the Royal Society B. 280(1761) doi:10.1098/rspb.2013.0580
 


Timothy Standish PhD works at the Geoscience Research Institute, based at Loma Linda University, California.