Hummingbird Study Illustrates Problem with Darwinian Explanations
Many people keep hummingbird feeders in their back yards, to enjoy the aerobatics of these colorful, quicker-than-the-eye, miniature marvels. Paul Nelson says, “There’s a kind of jewel-like quality that they have” that makes them so admirable. In Flight: The Genius of Birds, after seeing details about hummingbird science set to dazzling video, it’s no wonder Nelson speaks of the “exquisite workmanship” evident in their construction.
The big question facing science should be, “How did such exquisite workmanship come about?” How can a creature weighing only a few ounces perform maneuvers that flight engineers cannot begin to imitate? And yet evolutionists often seem fixated on much smaller questions, such as “How did one hummer evolve to be larger than another hummer?” A good example of this comes from the University of British Columbia, which announces, “Evolution — and skill — help hefty hummingbirds stay spry.” Looking right past the magnificent photo of a hummingbird’s iridescent feathers and beautiful head and eyes, the authors rush to give credit to blind processes of nature, right from the first word.
Evolved differences in muscle power and wing size — along with a touch of skill — govern hummingbirds’ inflight agility, according to new research in Science.
The findings by University of British Columbia biologists show that larger species of hummingbirds, despite their increased mass, are able to adapt to outmaneuver smaller species.
“Studies of bats, birds and other animals show that increases in body mass can have a detrimental effect on many aspects of flight,” says Roslyn Dakin, co-lead author on the study.
“But with hummingbirds, the correlated evolution of increased wing size and muscle mass helps larger species compensate for their greater body masses.”
You can summarize all the lessons of this study published in Science in just one sentence: “Bigger hummingbirds evolved bigger muscles, and smaller hummingbirds evolved smaller muscles, but all of them can maneuver equally well.” Fascinating. Science marches on.
It’s not that the scientists were lazy. Dakin et al. “recorded over 330,000 maneuvers, including many repeated maneuvers for each bird.”
How does agility evolve? This question is challenging because natural movement has many degrees of freedom and can be influenced by multiple traits. We used computer vision to record thousands of translations, rotations, and turns from more than 200 hummingbirds from 25 species, revealing that distinct performance metrics are correlated and that species diverge in their maneuvering style. Our analysis demonstrates that the enhanced maneuverability of larger species is explained by their proportionately greater muscle capacity and lower wing loading. Fast acceleration maneuvers evolve by recruiting changes in muscle capacity, whereas fast rotations and sharp turns evolve by recruiting changes in wing morphology. Both species and individuals use turns that play to their strengths. These results demonstrate how both skill and biomechanical traits shape maneuvering behavior.
Evolve, evolve, evolve. Everything is explainable by Darwin’s blind process of mistakes that survived the trash heap. That includes “both skill and biomechanical traits” because they are results of evolution, too. Is science advanced by work that ends up saying, “big hummingbirds evolved to be bigger, and small hummingbirds evolved to be smaller”? It wouldn’t matter if they recorded 500,000 maneuvers, or a million maneuvers. The fix was in: evolution would take all the credit.
This result explains why hummingbird maneuverability scales positively with species mass, even though mass has the opposite effect on individual performance: Larger species can achieve maneuverability through the evolution of disproportionate increases in muscle capacity and wing size.
It’s hard to even call natural selection a “process.” It’s more like a statement after the fact, a filter that allows one conclusion but omits all others. Natural selection is not an active agent; it doesn’t cause anything. The bird doesn’t choose to evolve, and the environment doesn’t make it evolve. The Darwinian just looks at the finished product, and says, “it evolved.” The reader is left looking at this masterpiece of flying jewelry, wondering if anything has been explained at all.
Thus, species-level evolutionary changes in muscle capacity and wing morphology affect different, correlated suites of behaviors.
No doubt this study took a lot of work, but the evolution statements do not logically emerge from the data. The scientists learned things about feathers, wing shapes, glycolysis in the muscles, and other measurable factors between different hummingbird species. But what’s evolution got to do with it?
Given that muscle capacity is the primary species-level trait associated with accelerations this result suggests that evolved changes in muscle capacity can compensate for relatively small wings.
The uselessness of evolutionary explanations can be seen by substituting the word “happenstance” for “evolve” in one of their concluding paragraphs:
A key result of our comparative analysis is that evolved [happenstance] changes in the wings primarily determine turns and rotations, whereas evolved [happenstance] changes in muscle capacity primarily determine translations. This indicates that different flight maneuvers evolve by [happenstance] recruiting different traits.
Lest any evolutionist complain that we’re leaving out the ‘selection’ part of the equation, it must be noted that selection is by happenstance, too. No mind is governing the outcome in the Darwinian view of the world. ‘But if selection didn’t operate, the bird would not survive!’ is the comeback. OK then, how satisfying is it to explain anything with the statement, “If it didn’t evolve, it wouldn’t exist”? It’s like the anthropic principle in cosmology, which (in one version) states, “If the universe were not finely tuned to an astonishingly intricate degree, we wouldn’t be here arguing about it, so it must have just happened to work out that way.” There’s something deeply unsatisfying in that kind of explanation.
The paper by Dakin et al., notice, is trying to explain hummingbird differences by evolution. Peter C. Wainright, in a companion piece in Science, points to the paper with the “how” word: “How hummingbirds stay nimble on the wing.” He says the authors “probe the evolution of flight maneuverability in hummingbirds”; he speaks of “the evolution” of hummingbirds; he mentions “the role of flight ability evolution in hummingbird diversification.” Our contention is, what’s the e-word got to do with it? For anything learned about hummingbird maneuverability due to wing shape, tail rotation, or muscle mass, does it help to say that evolution (happenstance) did it? Does this improve scientific understanding of a wonder of nature? Thinking people want to know how this wonder came about. Happenstance is not an answer. It is not an explanation.
You’ll learn more about hummingbirds in nine minutes of the Illustra film than in this paper with its 64 references and 18 mentions of evolution. You’ll learn that:
Engineers are light-years behind the bird that inspired robotic flyers.
Their wings can beat more than 100 times a second.
Hummingbirds are built for speed and maneuverability.
No other bird can fly backward and hover in mid-air while feeding on flowers.
The highly-maneuverable tail is a balancing organ the bird uses to guide direction.
The flight muscle represents about 43% of the bird’s mass.
Hummingbirds employ 3 specialized types of wing beats for forward, backward, and hovering motion.
Hummers have a unique shoulder joint that enables these flight strategies.
Unlike on any other bird, hummingbird wings generate lift on the backstroke.
The shoulder joint can rotate the wing 140 degrees by twisting the upper arm bone, making the entire wing invert on the backstroke.
To supply the muscles with oxygen, the bird’s heart beats as much as 1,250 beats per minute.
The nerve synapses fire at an incredible rate to make this muscular contraction possible.
The hummingbird consumes twice its body weight in nutrients each day.
During waking hours, the bird eats every 10 to 15 minutes.
A comparable diet for a human would be 150 pounds of food a day.
The hummingbird tongue is about twice as long as its beak.
The tongue acts as an automatic nectar trap (see video clip for demonstration).
The tongue traps nectar in less than 1/20th of a second, thousands of times a day.
Surely these observational facts cry out for an explanation more elegant than, “they evolved.” We respond to these observations, Paul Nelson concludes, like responding to the work of an artist. We doubt that any artist would appreciate having elegant craftsmanship attributed to happenstance.
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