Deep secrets: cetacean communication
by Lael Weinberger
Not until the 1940s did serious research begin on the world of underwater animal
sounds.1 For the first time,
thanks to the underwater microphone, researchers had the clicks, whistles and songs
of aquatic mammals at their fingertips. But the hard question of what the
animals were communicating has kept researchers busy ever since.
Great communicators
The vocabularies of the cetaceans (whales and dolphins) are stunning. A recent scientific
paper made headlines when researchers discovered that dolphins actually use their
whistles to tell the names of other individual dolphins,2 and might even refer to a third animal by name in
‘conversation.’
In contrast to most terrestrial mammals, the communications of whales and dolphins
are primarily auditory (sound) rather than visual.3,4 This auditory design is ideal
because vision is extremely limited underwater (appreciable sunlight extending to
only some 200 m (700 ft)5
). Many fish are vocally uncommunicative, but this does not mean that they are poorly
designed. The key is that social aquatic animals rely on auditory communication.4
The cetaceans are social animals and rely on their social structures for ecological
survival, whereas most sharks, for example, are quiet loners.
Giant voices for giant creatures
Blue whales are particularly impressive. They use low frequency, intense tones,
and have been known to dominate the low frequency sound field of an entire coastal
region for months.1 Their calls include extremely deep songs that actually
extend into the range of ‘infrasound’, too low for humans to hear.3,6 Infrasound can be heard over
extremely long distances—biologists can detect vocalizing whales from hundreds
of kilometres away.3 Researchers believe that the songs help orient the
whales in long distance travel, both by communicating to other whales, and by listening
to the echoes off the ocean floor to give them a sense of geographic position.3
Sperm whales produce intense high-frequency clicks, earning them the title of loudest
animal on earth
While baleen whales are specialized for low-frequency hearing, the toothed whales
are specialized for high frequencies.3 Sperm whales produce intense high-frequency
clicks,1 earning them the title of loudest animal on earth.7 The sperm whale ‘devotes about a quarter of
its body length’ to the spermaceti organ,8
whose main function is to focus and intensify loud clicks9 (at the equivalent of 170 decibels on land).7,10 What else this organ
is used for is still largely unknown, and some have even suggested that it is used
as a battering ram in competition with other whales.11 The function of the clicks is a matter of some
speculation as well! They are almost certainly used for echolocation,12 a sonar-like system of ‘seeing’ by
hearing echoes,13 and
there may be other uses.14
Designed to learn
Cetaceans and also seals are unique in another way: they are accomplished vocal
learners. Leading researcher Peter Tyack has noted: ‘Humans are the only terrestrial
mammal with well-developed abilities of vocal learning.’3 This
represents a significant puzzle for an evolutionist. Tyack continues: ‘ …
most nonhuman terrestrial animals appear unable to modify their vocal repertoire
based upon what they hear. Several groups of marine mammals, including seals, whales,
and dolphins, have highly developed skills for vocal learning.’3
The problem for the evolutionists is that the cetaceans are very far from humans
in the evolutionist’s ‘family tree’ (called a phylogeny). This
means that vocal learning had to evolve independently on land and in the water.
Not only that, but evolutionists also believe that cetaceans and seals were land
dwellers who entered the sea at different times. That means they had to independently
evolve countless specializations for marine life—including the exceedingly
unique gift of vocal learning. The evolutionary scenario looks more improbable all
the time.15
The case of whales’ abilities to learn sounds is just one example showing
that unique characteristics of animals cross the bounds of the evolutionary phylogenies
over and over. Biblical creationists would expect animals made by the same Designer
to have many similarities (a good design can be used in many settings). Evolutionists
often explain these circumstances as ‘convergent evolution’ (evolution
just happening to hit upon the same solution twice, independently), but this tends
to mask the true situation: the circumstances are not evidence of evolution, but
an anomalous fact to be explained away.16
Anomalous facts like this plague the evolutionists’ theories about whales.17 The more logical solution
is not convergent evolution, but common design by a Divine Designer, by whom ‘were
all things created’ (Colossians 1:16).18
Researching design
Design explanations are intuitive when discussing the whales’ communication
systems. Even evolutionists who don’t believe in a Designer have allowed the
word ‘design’ to slip into their writings on the topic. Peter Tyack
notes that a number of researchers believe that long-range signals have ‘design
features’ for communication.3
Even evolutionists who don’t believe in a Designer have allowed the word ‘design’
to slip into their writings
Design explanations are not ‘science stoppers,’ as some evolutionists
say. As creationists, we recognize that there is a purpose for whales’ communication.
We know that on Day 5 of Creation Week, God created the whales perfectly suited
for their needs. The belief in a purpose and order in the universe was the driving
force that gave birth to the scientific enterprise. As Johannes Kepler said, the
‘secrets [of science] … are set before our eyes like a mirror so that
by examining them we observe to some extent the goodness and wisdom of the Creator.’19 What could be more fitting
than studying the whales’ signals to discover the purposes for which the Creator
designed them? Because we expect to find engineering and design in the
whales, creationist scientists have the most hopeful and meaningful impetus for
research possible.
References and notes
- Cato, D.H. and McCauley, R.D., Australian research in ambient
sea noise, Acoustics Australia 30(1):13–20, 2002.
Return to text.
- Zabarenko, D., Dolphins recognise their own name, <www.abc.net.au/science/news/stories/s1634076.htm>,
25 July 2006. Janik, V.M., Sayigh, L.S. and Wells, R.S., Signature whistle shape
conveys identity information to bottlenose dolphins, Proc. Nat. Acad. Sci. USA
103(21):8293, 23 May 2006, Epub., 12 May 2006. Return
to text.
- Tyack, P.L., Functional aspects of cetacean communication,
in Mann, J., et al., eds., Cetacean Societies, University of Chicago
Press, Chicago, pp. 270–288, 2000. Return to text.
- Tyack, P.L., Dolphins whistle a signature tune, Science
289:1310–1311, 2000. Return to text.
- The ocean: mankind’s last frontier, Encyclopaedia
Britannica and Bantam Books, New York, p. 141, 1978. Return to text.
- Bedard, A.J. and Georges, T.M., Atmospheric infrasound,
Acoustics Australia 28(1):47, 50, 2000. Return
to text.
- Trivedi, B.P., Sperm whale ‘voices’ used to gauge
whales’ sizes, <news.nationalgeographic.com/news/2003/11/1103_031103_tvspermwhale.html>,
26 July 2006. Return to text.
- A more specialized form of the ‘melon’ found in
other cetaceans, where it is believed to act as a sound-focusing lens.
Return to text.
- Ref. 3, pp. 273–274; see also Whitehead, H., and Weilgart,
L., The sperm whale, in Mann et al., eds., ref. 3, pp. 167–168. Return to text.
- Chapman, D.M.F. and Ellis, D.D., The elusive decibel:
thoughts on sonars and marine mammals, Canadian Acoustics 26(2):29–31,
1998. Return to text.
- Carrier, D.S. et al., The face that sank
the Essex: potential function of the spermaceti organ in aggression, The
Journal of Experimental Biology 205:1755–1763, 2002.
Return to text.
- Ref. 3, p. 282, and ref. 7. Return to
text.
- Ref. 3, pp. 280–283. Echolocation poses basic problems
for evolution. See Weston, P., Bats: sophistication in miniature, Creation
21(1):28–31, 1998; <www.creation.com/bats>,
and Meyer, A., The world of whales, Creation
19(1):26–29, 1996; <www.creation.com/whale>.
Return to text.
- Norris, K.S., and Mohl, B., Can odontocetes debilitate prey
with sound?, American Naturalist 122(1):85–104,
1983. Return to text.
- See Sarfati, J., Refuting Evolution, chapter 5, Master Books, Arkansas,
USA, 1999. Return to text.
- On convergent evolution, see Menton, D.N.,
If we resemble apes, does that mean we evolved from apes?, <www.creation.com/apes>,
25 August 2000. Return to text.
- Woodmorappe, J., Walking whales,
nested hierarchies, and chimeras: do they exist?, Journal of Creation
16(1):111–119, 2002; <www.creation.com/walkingwhales>.
Return to text.
- See <www.creation.com/homologous>.
Return to text.
- Quoted in Nickel, J., Mathematics: is God silent?,
rev. ed., Ross House Books, California, USA, pp. 115–116, 2001.
Return to text.
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