The enigmatic narwhal
by Jean Lightner
The unique spiral tusk of the narwhal may make it the most unusual marine mammal
alive today. Narwhals are difficult to study since they inhabit the northernmost,
coldest regions of the ocean. They have been described as a deepwater species and
stay very close to the pack ice.1
In the summer some travel into the inlets off Baffin Island and the fjords of Greenland.
A recent study of narwhals has revealed some startling facts, particularly about
their tusks.
Image Wikipedia
Narwhal
Narwhals are classified in the suborder Odontoceti, toothed whales, which include
dolphins, porpoises, and killer whales. This may seem rather odd when you consider
the fact that you would not see any teeth if you could look in the mouth of a narwhal.
However, the narwhal’s most distinguishing feature, the long spiral tusk found
in most males and in some females, is actually a tooth with a most unusual growth
pattern.
Centuries ago, the narwhal tusk was sold as a unicorn horn; artists today still
often draw the unicorn horn with such a spiral pattern. In reality, the tusk is
the upper left incisor that erupts forward through the gums and bores a hole through
the upper lip, perhaps the only consistent example of body piercing found in nature!
This straight, tapered tooth spirals to the left as it grows up to three metres
(10 ft) long in the male. Weighing as much as 10 kg (22 lb), it ranges from one-third
to one-half the length of the animal’s body.2
In the few females who have a tusk, it is smaller and narrower than in males. On
rare occasions, narwhals have been found to have two tusks. In these instances the
tusk on the right is generally smaller, but still has a left-handed spiral.
There has been much debate over the purpose of the tusk. It has often been claimed
that it is used in fighting between males. Others have suggested that it might be
used in spearing prey, breaking ice, or digging. Recent research has established
the startling fact that, whatever else it might turn out to be used for, it functions
as a sense organ. Ten million tiny nerve endings connect the central nerve of the
narwhal tusk to the tusk surface, which is in contact with the frigid arctic waters!
The tusk can detect changes in water temperature, pressure, and particle gradients
(e.g. salinity).3,4
Additional studies have found that the tusk is surprisingly strong and flexible;
two characteristics which are not usually found together.5 It is hoped that further study may reveal insights
leading to the development of improved dental restorative materials for people.
Evolutionary puzzle
the narwhal tooth is puzzling because it is unlike any other mammal tooth
Evolutionists believe all whales, including the narwhal, descended from hoofed
mammals (ungulates). To support this belief, they search for animals that seem to
show a gradual transition between the two.6
The narwhal tooth is puzzling because it is unlike any other mammal tooth in its
spiral structure, asymmetry (only the left tooth is usually involved), and strange
distribution (among most males and some females). There is no pattern of gradual
change in its alleged ancestors; the tooth appears truly unique.
In reality, a far bigger puzzle for the evolutionist is the origin of teeth in general.
In most mammals teeth just happen to be in the right place for chewing. To an evolutionist,
all structures such as eyes, teeth, and lungs are the result of random mutations
(which add variety) and natural selection (which removes variety). While mutations
and natural selection do occur, no such random process can be expected to create
information to put well designed structures in the right place at the right time.
Were narwhals originally created with tusks?
In the past, some Christians mistakenly believed that all animals were created by
God just as we see them today. While this view recognized God as Creator and that
animals were well adapted to their environments, to insist on it ignores the real
history of the world given in the Bible. Sea creatures were told after their creation
to be fruitful, increase in number, and fill the seas (Genesis 1:21–22).
Similar comments regarding filling the earth were made to birds and humans, and
then land animals.7 Thus, God created
living things to reproduce and fill the earth and seas. Due to the effects of such
catastrophes as the Curse and the global Flood, many harsh and different environments
have arisen on the earth since creation. Thus it was important for creatures to
be designed to have the built-in potential to vary, so as to be able to adapt and
cope with changing environments.
Mutations can add to the variety seen in different creatures. There are thousands
of mutations that cause serious disease or death. Some mutations do not appear to
harm the animal8,9 while others can even be beneficial
under certain special circumstances.10
Some mutations appear to be programmed and occur to help the creature survive in
certain unusually harsh conditions.11
Yet in every case studied so far, these mutations involve a loss of information.
They can only modify structures that already exist, they cannot explain the origin
of well designed structures.
At first glance it would seem that the narwhal tusk must have been designed. It
has a unique spiral and many sensitive nerve endings. It can sense changes in temperature
and pressure.
However, normal teeth can detect these changes as well; it is just that they typically
remain in the mouth. Normal teeth cannot detect changes in salinity because the
nerve endings in the centre of the tooth do not contact the surface. Also, normal
teeth are protected by a hard layer of enamel, which is essentially absent in the
narwhal tusk.
As a veterinarian, there are several characteristics of the narwhal tusk that lead
me to believe it is the result of degenerative changes affecting one of the teeth
God originally created in the kind that gave rise to today’s narwhal. First, it
is asymmetrical, that is it is found on one side, but not the other. Mammals are
designed with bilateral symmetry; the left side of the animal is a mirror image
of the right.12 When one side
appears significantly different from the other, it is a sign of abnormality.
Second, there is no modification in the upper lip that ‘anticipates’
the emergence of the tusk. Instead, the tooth grows right through the upper lip.
This is very uncharacteristic of the type of design seen in animals. Normally there
are a myriad of things all designed to work together. For example, upper teeth are
designed to oppose lower teeth; the tongue is designed to fit behind them; one part
of the digestive tract is designed to work together with the other parts for a common
goal; nerves and blood vessels are designed to enable the digestive system to work
properly and benefit the rest of the body, and so forth.
The tusk is absent in over half the narwhal population (juveniles and most females).
This indicates that it is not essential to survival.13
The tusk may provide some advantages to the narwhal in their limited arctic range;
however, it is possible that the tusk is one of the reasons that they have such
a limited range.
In the fetal stage, the narwhal has six pairs of upper teeth and two pairs of lower
teeth. These teeth do not undergo normal development later in life. It is easy to
see how teeth that do not completely develop can be the result of degenerative changes.
The information for tooth development controls how teeth are formed, when they are
formed, and where they are formed.
Just as there is information that starts tooth growth, there is also information
that stops it. It appears that something has happened to the information that stops
tooth growth for one of the narwhal’s teeth, so a tusk develops.
The spiral structure results from different parts of the tooth growing at different
rates. Studying examples of abnormal teeth highlights how astoundingly complex teeth
are and how many factors need to work together for their proper development.
The ‘sensational’ tooth of the amazing narwhal reminds us that changes
have occurred since creation. In spite of these changes, we can still see the awesome
design of our infinitely wise God in His creatures.
References and notes
- Reeves, R.R. and Tracey, S., ‘Monodon monoceros’,
Mammalian Species 127:1–7, 15 April 1980.
Return to text.
- Weighing about 1,450 kg (1.5 tons). Return
to text.
- News: Mystery of the world’s strangest tooth solved,
British Dental Journal 200(1):8, 2006.
Return to text.
- Malkin, C., Interview: Nothing but the tooth, New Scientist
185(2485):46–49, 5 February 2005. Return
to text.
- This appears to be related to the amount of mineralization
and the direction of the fibres. Narwhal dentin is softer and less mineralized than
human or cattle dentin; both narwhal and human cementum are softer and less mineralized
than cattle cementum. Brear, K., Currey, J.D., Pond, C.M. and Ramsay, M.A., The
mechanical properties of the dentine and cement of the tusk of the narwhal Monodon
monoceros compared with those of other mineralized tissues, Arch. Oral. Biol.
34(8):615–621, 1990; Currey, J.D., Brear, K., Zioupos, P.,
Dependence of mechanical properties on fibre angle in narwhal tusk, a highly oriented
biological composite, J. Biomech. 27(7):885–897,
1994. Return to text.
- Williams, A. and Sarfati, J., Not at all like a whale,
Creation 27(2):20–22, 2005; <www.creation.com/pakicetus>.
Return to text.
- Genesis 1:22,28, and after the Flood, Genesis 8:17; 9:1.
Return to text.
- Lightner, J., Colourful creature coats, Creation
28(4):33–34, 2006. Return to text.
- Lightner, J., The Riddle, Creation 27(4):30–32,
2005; <www.creation.com/dorset>. Return to text.
- Wieland, C., Beetle bloopers, Creation 19(3):30,
1997; <www.creation.com/beetle>. Return to text.
- So far, these directed mutations have only been identified
in bacteria. Directed mutations pose a problem for evolutionists because they believe
mutations to be random, chance events. Directed mutations imply a Programmer for
the genome; Lightner, J., Special tools of life, <www.creation.com/tools>.
See also Batten, D., The adaptation of bacteria to feeding on nylon waste, Journal
of Creation 17(3):3–5, 2003; <www.creation.com/nylon>.
Return to text.
- This is not true of the viscera (heart, lung, stomach, liver)
but is true externally and in the mouth. Return to text.
- Its absence may of course be due to loss mutations, as has
happened in many elephant populations. Return to text.
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