Vestigial Flightless Birds

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In an article about vestigial organs Live Science writes: “Ostriches and cassowaries are among several birds that have wings that are vestigial. Besides the cassowary, other flightless birds with vestigial wings are the kiwi, and the kakapo (the only known flightless and nocturnal parrot), among others. In general, wings of a bird are considered complex structures that are specifically adapted for flight and those belonging to these flightless birds are no different. They are, anatomically, rudimentary wings, but they could never give these bulky birds flight. The wings are not completely useless, as they are used for balance during running and in flagging down the honeys during courtship displays.”

In May 2008 New Scientist wrote “The existence of something as spectacularly de trop as the ostrich wing is only a problem for those who believe in an intelligent designer.”

Live Science

Editorial Comment: The best comment on the ‘vestigialness’ of ostrich wings comes from a letter to New Scientist by Sibbele Hietkamp, an ostrich farmer in South Africa, who wrote: “Laura Spinney describes ostrich wings as ‘spectacularly de trop’ (17 May, p 42). I have kept ostriches for 18 years and can testify otherwise.” He goes on to describe how ostriches use their wings for many important functions: thermoregulation; providing stability when running and enabling rapid right angle turns; courtship displays and stability while mating; warning signals and other communication; nest building; and providing shade and shelter for young. (New Scientist letters 21 Jun 2008, p24).

Sibbele Hietkamp’s observations remind us that practical observations and experience from those who work with living things or in a particular environment are more of use to science than the beliefs of journalists and academics who are not. Even though they can’t fly ostriches are particular efficient runners and are able to function well in a variety of environments.

If you consider the overall anatomy and physiology of the ostrich, rather than just its wings, you will see that it is a functioning creature that works well, so the New Scientist quip against intelligent design wasn’t very intelligent. The wings of other large flightless birds, e.g. emus, cassowaries, penguins, rheas, fit into the same category as ostrich wings – an extreme variation of wings, but still functional and useful structures that are part of a fully functional creature whose fossils show no evidence the bird has ever flown and was never meant to fly, but which seem very intelligently designed for running, cooling, mating and protecting young.

There are some birds that seem to have lost the ability to fly due to defects in their wings but they have survived in a small protected environment, e.g. flightless cormorants in the Galapagos Islands or the Titicaca Flightless Grebe. These are usually classified a separate species within a genus of similar flying birds, suggesting that they are descended from a flying bird that suffered some genetic defect in the past. Because the defective birds find it easier to mate with each other, they soon become genetically isolated and effectively become a separate species. The wings of these disabled birds could be called “vestigial” but this loss of function is not evolution – it is degenerate loss, which is the opposite of evolution. The kiwi of New Zealand seems to be an extreme example of loss. It has small wings, but no wing muscles, which means it has no muscle covering over its chest and is easily killed by dogs and other animals. It has only survived by living a secluded nocturnal life in forests where there were no predatory mammals before humans accompanied by their pets and other mammals came to live in New Zealand.

Penguin wings are sometimes called vestigial, but even though they are flightless, penguin wings are well suited for their aquatic lifestyle. Their wings function as efficient flippers with powerful muscles and that enable them to move through the water with a movement that is similar to flying, and the abundant fossil record of penguins shows they were once much larger but show no evidence of ever having larger wings.

Any real or partial vestigial organ is a reminder that the real history of the world is Descent with Modification from an initial created perfection. It was followed by the degeneration caused by the fall of Man which bought about God’s cursing of the ground, and the later judgement of Noah’s Flood. This caused massive degradation of the environment, and was followed by genetic isolation and resultant inbreeding amongst all living groups (man included) as they spread out across the globe after the flood. This in turn has resulted in a great increase in genetic defects and loss of function, e.g. the loss of wing use observed in the hatchlings of many ducks and wild birds following chemical pollution of the environment. The remnant pitiable wing structures their offspring had are no use in flight so they are condemned to spend their futures on ground, water, or climbing trees – if they don’t get eaten first. (Ref. Philosophy, classification, devolution)

Creationist Challenge: Sibbele Hietkamp's observations about the remaining functions of ostrich wings in the item above bring to light a gap in scientific nomenclature which needs to be resolved. It is worth pondering the option that some organs originally had more than one function, and can actually survive considerable loss of function, while continuing to exist with much reduced functional roles. An example is the present day dwarf legs in many reptiles, whose fossils show they once had full legs. Such degenerate organs are no longer any use in walking, but are still large enough to hold on to a female in mating.

Such organs cannot be considered totally vestigial till all function has been lost, so we propose a new term be created to describe we recommend such functionally reduced organs be labelled as dystrophic which we define as an originally multifunctional appendage or organ which has lost some of its original function or functions, but has not yet become non-functional. We derive the word dystrophic from the disease muscular dystrophy, a degenerative disease that causes loss of function in muscles because one structural protein is missing.

Additional Prediction: original organs will in most cases be discovered to have been multifunctional as well as having backup (via what are commonly viewed as redundant support systems) and thus are capable of considerable loss of function before becoming useless and a detriment to the creature.

Evidence News, 7 October 2009

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