Vestigial Organs

According to Wikipedia, “Vestigiality refers to genetically determined structures or attributes that have apparently lost most or all of their ancestral function in a given species, but have been retained through evolution…The emergence of vestigiality occurs by normal evolutionary processes, typically by loss of function of a feature that is no longer subject to positive selection pressures when it loses its value in a changing environment.” (1) Austin Cline adds, “A vestigial organ or structure is any organ or structure found in a species which is not being used as it is in other species.” (3)

There is something worth clarifying at this point. “Contrary to popular belief, vestigial organs and vestigial structures aren’t necessarily useless or functionless…All that’s necessary for an organ or structure to be labeled ‘vestigial’ is for there to be homologies in other species where the use or function is clear, but that same use or function is not the case for the species in question.” –Austin Cline (3)

Technically, creationists do not object to the concept that an organ or structure may lose some or even all of its function. The fall of man combined with changing environmental conditions in the post-flood world could theoretically have led to loss of function. Creationist Dr. David DeWitt from AiG ministries has noted that, “Creationists understand that there has been degeneration and mutation since the Fall. We also expect that there would be a significant loss of information for many genes. The loss of genes for organs that do not significantly impact survival in a negative way could be quite prevalent. Thus, for the creationist, there should be no problem with an organ or structure in man that has lost some functionality. However, another possibility is that we have just not determined or understood the function properly yet. Creationists that I know do not deny that there are organs in man that have lost some of their functionality. However, they do reject the notion that those organs were inherited from a common ancestor with apes or other animals.” (6)

Arguments For and Against Vestigial Organs:

Appendix

The argument that it’s vestigial:

Argument: “No one knows the actual original function of the appendix, but Charles Darwin proposed it was once used by primates to digest leaves. Now, the appendix in humans seems to be a depository of sorts for bacteria that is used in the colon to aid in digestion and absorption.”-Heather Scoville, “evolution expert” (4)

Response: If you know what the current function of the appendix is, but don’t know what its function used to be, why not assume that the current function has always been its function?

Argument: “Does an appendix do us any good at all? If so, it’s not obvious. Removing it doesn’t produce any bad side effects or increase mortality (in fact, removal seems to reduce the incidence of colitis.” –Jerry Coyne, Why Evolution is True

Response: The appendix does have a purpose (as Coyne admits, see below). To argue that the appendix is vestigial on the basis that removing it reduces the incidence of colitis is like saying removing your legs reduce the incidence of ACL injuries. Please!

The argument that it’s NOT vestigial:

  • It is a storehouse of beneficial bacteria that help us digest food.
    • “[A surgeon named William] Parker himself has been one of the many researches to be involved in actual experimental research elucidating these functions of the appendix. He and his colleagues have suggested the appendix provides a ‘safe house’ for beneficial gut bacteria to shelter when dangerous pathogens temporarily out-compete them.” (5)
    • “But to be fair, it [the appendix] may be of some small use. The appendix contains patches of tissue that may function as part of the immune system. It has also been suggested that it provides a refuge for useful gut bacteria when an infection removes them from the rest of our digestive system.” –Jerry Coyne, IBID
    • “It’s hard to figure out what the appendix does when you’re studying super clean animals and people.” –Bill Parker, assistant professor of surgery at Duke University Medical Center (2)
    • Where diarrheal disease is common, the appendix is vital for repopulating the intestines with helpful bacteria after the illness.

Coccyx (tailbone)

The argument that it’s vestigial:

Argument: The supposed remnant of tails once possessed by our mammalian and reptilian ancestors eons ago. The fact that there can be a variable number of bony segments (from 3-5) is cited as evidence. Also, some babies are “born with tails.”

Response: The argument that babies can be born with tails is misleading. These are types of fatty tumors that do not possess bones or muscles and are surgically removed.

  • Laura Spinney acknowledges that the coccyx now has a “modified function, notably as an anchor point for the muscles that hold the anus in place.” (7)
  • Jerry Coyne admits the same: “It still has a function (some useful muscles attach to it.” IBID

The argument that it’s NOT vestigial:

  • It is actually the anchor point for the muscles that form the entire pelvic diaphragm.
  • There are rare instances where babies are born with “tails.” This is seen as an atavism (sporadically expressed remnants of ancestral features). But notice this explanation from Dr. Gary Parker: “It doesn’t have any bones in it; it doesn’t have any nerve cord either. The nervous system starts stretched out open on the back. During development, it rises up in ridges and rolls shut. It starts to ‘zipper’ shut in the middle first, then it zippers toward either end. Once in a while it doesn’t go far enough, and that produces a serious defect called spina bifida. Sometimes it rolls a little too far. Then the baby will be born – not with a tail, but with a fatty tumor. It’s just skin and a little fatty tissue, so the doctor can just cut it off.” (10)

 Tonsils

 

The argument that it’s vestigial:

Argument: An online user named “Newdarwinian” said, “They seem to have lost much of their immune system function, though the argument over their vestigial status is not settled.” (9)

Response: “Seem” and “not settled” indicate that the tonsils cannot be used as proof of evolution in the slightest. Also, a loss of some function doesn’t contradict the creation model.

The argument that it’s NOT vestigial:

  • Tonsils have immunological benefits in the entrance to the pharynx.
  • “…tonsillectomy is the most frequently performed piece of surgery. Doctors once thought tonsils were simply useless evolutionary leftovers and took them out thinking that it could do no harm. Today there is considerable evidence that there are more troubles in the upper respiratory tract after tonsil removal than before, and doctors generally agree that simple enlargement of tonsils is hardly an indication for surgery.” – Ratcliff, J.D., Your Body and How it Works, Delacorte, New York, p. 137, 1975.

Spleen

The argument that it’s NOT vestigial:

 

  • Helps to spot infections. (2)
  • Filters our red blood cells that are damaged or old. (2)
  • It was previously believed that monocytes (white blood cells essential for immune defense and tissue repair) were made in the bone marrow and stored in the bloodstream, but a new study shows that the spleen contains 10 times as many monocytes as blood. (2)
  • “What’s more, the spleen is the source of 40-50% of the monocytes involved in nursing lab mice back to health after a heart attack.” –Filip Swirski of Massachusetts General Hospital’s Center for Systems Biology (2)
  • A 1877 study published in The Lancet followed the health of WW2 vets over 20 years, some with spleens and some without. The spleen-less men were twice as likely to die from heart disease and pneumonia.

Male Nipples

The argument that it’s vestigial: 

Argument: “When we inspect Homo sapiens, alleged to be Nature’s most illustrious accomplishment, it is obvious that the job could have been done much better! As an example, let us consider the male breast, a structure encountered in all mammals. What did Nature have in mind for this decorative appendage? Was it supposed to serve a real purpose, or was it a whimsical act committed during a moment when Nature was in a joking mood?” (R. Rothenberg, The complete Book of Breast Care, 224, 1975)

Response: This is actually a problem for evolution because…

  • According to evolution, male nipples must have had a more robust function in the past…but what would it have been? Did males breastfeed infants? Were all males once females?
  • Evolution posits that mammals evolved from reptiles and that the divergence of male and female took place first in reptiles. Why would another divergence need to occur in our mammalian ancestors? In other words, males and females diverged long before breast feeding began in mammals according to evolution.

The argument that it’s NOT vestigial:

  • Male nipples are not vestiges of evolution, but of embryology.
  • “In what is known as the biphasic model, one nonsexual zygote begins and the genetic differences that produce the sexual differences exert their effect as development proceeds. Males and females are physiologically identical in the early stages of embryological development.” –Jerry Bergman (11)
  • “Men have nipples because they have already started to develop at the time when the male hormonal signal to differentiate is activated. Male development is therefore a result of sexual differentiation designed to produce sexual dimorphism.” –Jerry Bergman (11)
  • “The rudimentary mammary duct system remains indistinguishable at birth. Male and female breast tissue remains poorly developed until influenced by estrogen in the early stages of puberty in the female. If nipples and breasts are ‘useless’ to males, they are equally useless to prepubescent girls, and for that matter are ‘useless’ to any woman who is not breastfeeding a child.” –Dr. Tommy Mitchell (8)
  • Interestingly enough, male nipples also serve as a source of sexual stimuli.

Wisdom Teeth

The argument that it’s vestigial:

  • Wisdom teeth aren’t necessary.
  • Because of crowding, they often have to be removed.
  • 35% of people do not develop wisdom teeth.

The argument that it’s NOT vestigial:

  • Wisdom teeth are functional for people who develop them and have haws large enough to accommodate them.
  • However, it may be that due to natural selection and variation (due to changes in diet), our jaws are generally less capable of handling them as they once were. This would only prove a loss of information, something allowed within the creation model, but does not prove macroevolution.
  • Neanderthal and other human fossils show that in the past, there were few problems with wisdom teeth.

Arrector Pili (Goose Bumps):

The argument that it’s vestigial:

  • In many animals, this is a reflex that generates warmth and/or makes the animal appear larger (as a defense mechanism, as in cats). It is a response to cold or high emotions.
  • “This whole process is vestigial for humans because we do not have enough hair or fur to make it worthwhile…Humans still have the response of the arrector pili muscle pulling up the hair shaft, but lack enough fur or hair for the response to actually work.” (4)

The argument that it’s NOT vestigial:

  • The “AGAINST” argument is predicated on evolutionary presuppositions.
  • It is a matter of degree. Because our own hair appears “puny” in comparison to that of other animals, it is assumed that our goose bumps are functionless.

General Quotes About Vestiges

“But as technology has advanced, researchers have found that, more often than not, some of these “junk parts” are actually hard at work.” –Maggie Koerth-Baker, National Geographic News, July 30, 2009 (2)

“History is littered with body parts that were called ‘useless’ simply because medical science had yet to understand them.” –Jeffry Laitman, director of anatomy and functional morphology at New York’s Mount Sinai School of Medicine (2)

SOURCES:

(1) http://en.wikipedia.org/wiki/Vestigiality

(2) http://news.nationalgeographic.com/news/2009/07/090730-spleen-vestigial-organs.html

(3) http://atheism.about.com/od/evolutionexplained/a/VestigialOrgansAppendix.htm

(4) http://evolution.about.com/od/evidence/tp/Vestigial-Structures-In-Humans.htm

(5) https://answersingenesis.org/human-body/vestigial-organs/appendix-useless-vestige-or-evolutionary-innovation/

(6) https://answersingenesis.org/human-body/vestigial-organs/setting-the-record-straight-on-vestigial-organs/

(7) http://www.newscientist.com/article/dn13927-five-things-humans-no-longer-need.html?DCMP=ILC-hmts&nsref=news9_head_dn13927

(8) https://answersingenesis.org/human-body/vestigial-organs/why-do-men-have-nipples/

(9) http://www.answers.com/Q/Why_are_tonsils_a_vestigial_structure

(10) http://www.christiananswers.net/q-eden/edn-c024.html#1

(11) http://creation.com/is-the-human-male-nipple-vestigial#endRef25

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