Grand Movements Of Nature: Evolutionists’ ‘Non-Answer’ To Animal Migration
|September 22, 2009||Posted by Robert Deyes under Intelligent Design|
The NOVA documentary The Incredible Journey Of The Butterflies, which aired on public television earlier this year, details a phenomenon that in recent years has captivated biologists worldwide- the North American Monarch butterfly’s 2500 mile long migration to the Mexican Sierra Madre mountains. Both the sheer scale of the journey and the paucity of models in the scientific literature that adequately explain its evolutionary origins are plainly evident (1).
The late paleontologist Stephen Jay Gould took a rather nebulous stab at explicating the origins of another migratory feat- that of the green turtle’s trans-Atlantic breeding trek from Brazil to the ‘pinpoint of land’ we now call Ascension Island (2). Having soundly carved up biologist Archie Carr’s migratory drift hypothesis (which would have us believe that the migratory distance used to be much shorter and extended gradually as continents moved apart), Gould treated us to his own momentary reliance on obscurity. In Gould’s words “the mechanism of turtle migration is so mysterious, that I see no barrier to supposing that turtles can be imprinted to remember the place of their birth without prior genetic information transmitted from previous generations” (2). It seems that for Gould at least, the bigger the evolutionary mystery, the more scope one would have for assuming what one wished to assume.
The rock pigeon, a favorite of Darwin’s and a center piece in his treatise on artificial selection, uses the sun as a compass to get around (3-5). Equipped with an extraordinary capacity to perceive UV and polarized light, as well as a keen ability to detect the earth’s magnetic fields, the rock pigeon is today considered to be a champion of directional orientation. As Fred Ryser noted in his textbook account, “the [pigeon’s] sun compass employs the apparent movement of the sun along an arc across the sky -the ecliptic-during the day…On overcast days or when its capacity to see the sun is eliminated…the pigeon practices directional orientation by using geomagnetism…the pigeon’s magnetic compass somehow senses [the] downward inclination in the magnetic field and the brain interprets it as north”(4). Underpinning such a phenomenal capability are numerous crystals of iron oxide that in the pigeon’s brain align with the earth’s magnetic field “like the iron needle in a compass” (5).
Just as remarkable is the Arctic Tern’s aptitude for long distance precision flight. Flying in flocks of 12-25 individuals at altitudes of 30-150 meters, terns cover 40,000 km each year between their polar wintering and breeding quarters (6). One might assume that for these and other migratory birds, land masses en route could provide necessary resting points and navigational aids to keep them energized and on track. And yet some notable cases defy such a facile dismissal of the facts. The American golden plover, for example, can fly over the Atlantic from Canada to the northeastern coast of South America with sparse visual cues and without so much as a touchdown or a re-supply of food (7). Similarly, many ruby-throated hummingbirds fly 500 miles non-stop in their annual northward migration across the Gulf of Mexico. According to one review, such a compulsion to fly is ingrained in the very fabric of the young ‘hummer’: “there’s no memory of past migrations, only an urge to put on a lot of weight and fly in a particular direction for a certain amount of time, then look for a good place to spend the winter” (8).
McGraw Hill’s third edition of The Nature Of Life carried details of a study that confirmed the homing abilities of a long-winged seabird called the shearwater: “When experimenters transferred an individual shearwater…from its home in Great Britain to a new location in Massachusetts, the remarkable bird was back on its nest in 12 days, having crossed 4800 miles of trackless ocean” (5). Key experimental data corroborates the assertion that an established endogenous circannual clock is critical for ensuring appropriate pre-migratory fattening, moulting and reproduction. Writing on the common warbler, for example, Max Planck Institute’s Eberhard Gwinner emphasized how “rhythmic waxing and waning of nocturnal [circannual activity]…is usually accompanied by variations in migratory fattening (indicated by an increase in body mass) and followed by a moult in winter and a phase of reproductive activity in summer” (9). Most remarkable of all is the finding that the circannual clock is responsible for setting not only the timing but also direction and duration of migration (9). Day length (or photoperiod) provides a critical trigger for getting migration started (9).
How might evolutionary processes have given rise to migratory behaviors? In their book Nature’s IQ, Balazs Hornyanszky and Istvan Tasi are candidly open about their view on the matter- natural selection could not have been the operative mechanism (10). The exactitude of food intake relative to energy expenditure for trans-oceanic birds forms an important platform upon which they develop their rationale- too much food prior to becoming airborne and levels of body fat would be incompatible with effective flying (9). Too little food and the fat reserves would be insufficient for completion of the journey. The end result would be an almost certain death, perhaps an out of control plunge into the merciless seas below. Hornyansky’s and Tasi’s swathing attack on the evolutionists’ ‘non-answer’ appeals to our deepest intuitions. Analogizing bird migration to human feats of navigation they write:
“Many [innate] complex abilities must be simultaneously present for migratory birds to perform such impressive feats, and these abilities and knowledge have to work in perfect harmony. If we want to climb the highest peak of the Himalayas, Mount Everest, we have to create a detailed plan to be able to reach our goal. It would be foolish to think that merely by a series of fortunate accidents, in time we will suddenly find ourselves there. Not only do we have to make an all-encompassing plan, but we also have to execute every detail of it. If we disregard just a single factor…our undertaking, despite all our efforts, could end in failure. The migratory system of birds, too, is able to function only in its entirety, and the superficial assumptions about its ‘gradual evolution’ get caught in the filter of logical thinking” (10).
Those in favor of evolution’s ways openly struggle to understand the selective advantage afforded by the migratory birds’ seemingly deliberate draining of precious resources. By their own admission “Migration exacts a high toll [as] grizzlies wait in streams and gorge on exhausted salmon migrating home from the sea, and falcons feast on fatigued songbirds arriving at their winter home in Africa. Fuel used by muscles to propel wings, fins, and legs is unavailable for reproductive activities, and time spent on the move is time not spent gathering food” (5). They counter their self-imposed quandary by assuming a priori that selection ‘favors the brave’ and that over time survival benefits must have outweighed such costs. Evolution is after all a ‘fact’ and so what must have happened must have happened. Such circular reasoning of course gets us nowhere and leaves the above functional challenges unanswered. In short, evolutionists are today caught in their own Gouldean-style reliance on obscurity.
1. Robert Deyes (2009), Questioning The Role Of Gene Duplication-Based Evolution In Monarch Migration, Access Research Network, See http://www.arn.org/blogs/index.php/2/2009/03/01/questioning_the_role_of_gene_duplication
2. Stephen Jay Gould (1992), The Panda’s Thumb- More Reflections In Natural History, Published by W.W Norton and Company, New York, pp.31-34.
3. Charles Darwin (1859), The Origin of Species By Means of Natural Selection Or The Preservation of Favored Races In the Struggle For Survival, Modern Library Paperbacks Edition (1998), New York, p.42.
4. Fred A Ryser Jr (1985), Birds Of the Great Basin: A Natural History, University Of Nevada Press, pp.290-291.
5. John H Postlethwait and Janet L. Hopson (1991), The Nature Of Life, 3rd Edition, McGraw Hill, New York, pp.922-923.
6. Gudmundur A. Gudmundsson, Thomas Alerstami, Bertil Larsson (1992), Radar observations of northbound migration of the Arctic tern,Sterna paradisaea, at the Antarctic Peninsula, Antarctic Science, Volume 4, pp. 163-170.
7. See American Golden Plover ‘Fact Sheet’ On The National Wildlife Federation Site http://www.nwf.org/birdsandglobalwarming/birdprofile.cfm?bird=American+Golden-Plover
8. See Hummingbirds.Net at http://www.hummingbirds.net/migration.html
9. Eberhard Gwinner (1996), Circadian And Circannual Programs In Avian Migration, The Journal of Experimental Biology, Volume 199, pp.39-48.
10. Istvan Tasi and Balazs Hornyanszky (2009), Nature’s IQ: Extraordinary Animal Behaviors That Defy Evolution, Torchlight Publishing, Badger, CA, pp.93-94