Bats: sophistication in miniature
by Paula Weston
When it comes to hunting and catching prey, few creatures use a system as complex
and highly specialized as that of the insect-eating bats.
These small bats (of the sub-order Microchiroptera) rely on echolocation, or ‘bat
sonar’ as it is commonly called, for hunting in the dark.
The bat sends out a high-pitched sound, then listens for the echoes reflected from
nearby surfaces and objects. By detecting its own reflected sounds, often among
other distracting noises, the small mammal is able to avoid obstacles, and obtain
the information necessary for tracking and catching an insect. This amazing system
can accurately discriminate between an individual insect and any others close by.1
To achieve this, the bat has a number of very special features. These include a
specialized larynx (an organ in the throat) which allows it to produce intense,
high-frequency sounds (ultrasound). High frequencies (i.e., short wavelengths) are
essential so the bat can determine the fine details of the objects which reflect
the sounds.1
Bats have always been bats
The ‘earliest’ bat fossils (i.e. those buried lowest in the geologic
record) come from the Eocene layers. According to evolutionary reasoning, these
are roughly 50 million years old. Yet they are 100% bats (there is no trace of any
partway development of the wing, for instance). They show evidence of having had
fully functioning echolocation.
The species usually given in textbooks as the ‘earliest bat’ is Icaronycteris
index from North American Eocene. However, more recently, specimens from
the (likewise Eocene) Messel oil shale pit in Germany have shown many more interesting
features. Shown here from the Messel shales is Palaeochiropteryx tupaiodon,
featured in German creationist Dr Joachim Scheven’s Lebendige Vorwelt
museum. Note that this ‘oldest bat’ is as specialized and ‘evolved’
as any of today’s bats.
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From the echoes of these ultrasonic sound pulses, the bat determines not only the
distance and direction of its prey, but also its speed, size, shape and surface
texture, all while in full flight.2
The bat’s large external ears act as efficient collectors and resonators of
the high-pitched sounds.1 Its internal ear mechanisms are highly sensitive.
The process also requires a sophisticated integration of the vocal and auditory
centres of the brain.3 Not only must
the nervous system of the bat analyze, in a few thousandths of a second, the reflected
sound of its own pulse, it must separate this echo from those sent out by other
bats, and from others of its own pulses.4
This is an astonishing technological feat.
For echolocation to work successfully, both emitting and receiving organs within
the bat’s skull must co-operate. This fact makes life difficult for evolutionists
attempting to explain how the bat developed its sonar, or, more importantly, how
the species survived as a hunter while this supposed evolution was taking place.
Things are even tougher for the evolutionist with the knowledge that the ‘oldest
known’ complete fossils of bats (actually, all this means is that they are
the lowest found so far in the geologic record), of so-called Eocene age, show indications
of a fully-developed echolocation system. According to the evolutionary time scale,
these bats (which, by the way, look essentially the same as modern bats) lived around
50 million years ago!5
Dr Duane Gish, in his book
Evolution: The Fossils Still Say NO!, explains how evolutionists believe
the development of flight in mammals took millions of years, from a number of rare
‘good’ mutations produced randomly among an ocean of bad mutations.
after A.H. Mueller, Lehrbuch der Palaeozoologie, 1959, p. 41

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here for larger view
Match the bat’s teeth
We are often led to believe that such and such a fossil animal must have eaten a
certain type of diet because ‘we know from the shape of its jaws and teeth’.
However, the examples here suggest that it is not possible to be dogmatic about
this. It is obviously relevant to discussion of what various animals were eating
before the Fall, and how this may have altered afterwards, as the
‘dracula’ article explores for vampire bats.
The Bible indicates that animals were not fighting and eating each other before
the sin of Adam. We see here that teeth are, of themselves, no reason to insist
that an animal may not be (or once have been) a plant eater. For a fuller discussion,
see The Creation Answers Book.
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This process supposedly converted the forelimbs of the land-dwelling ancestor of
the bat into wings, as four fingers of each hand gradually reduced in length. The
wing membrane also had to be generated by a series of ‘good’ mutations
which also produced, step by step, flight muscles, and the numerous unique arrangements
of tendons, nerves and blood vessels required for the specialized features of the
bat.6
If this were true, Gish argues, the fossil record would produce a series of transitional
forms documenting intermediate stages, revealing, for example, the gradual conversion
of forelimbs to wings as the fingers became longer and longer.
However, no such evidence linking bats to ground-dwelling mammals exists. Evolutionists
simply describe bats as being ‘already highly evolved when they first appeared
in the fossil record.’7 As mentioned
above, the ‘earliest’ bat skeletons, supposedly 50 million years ‘old,’
are virtually indistinguishable from living bats, with fully formed wings.
Bats belong to the mammalian order Chiroptera, which comprises two sub-orders, the
Microchiroptera (as described earlier), and the Megachiroptera (megabats), comprising
larger bats including flying foxes, or fruit bats. Unlike the Microchiroptera, the
Megachiroptera, though they also usually fly at night, mostly locate their food
by sight, except for one genus, which echolocates like the smaller insectivorous
bats.
These two groups pose an interesting problem for evolutionists. They have so many
features in common that it was naturally assumed that they must have inherited these
features from the same (common) ancestor. However, the brains of megabats have very
specialized visual pathways which are very much like those of primates, the order
into which apes, monkeys and humans are classified.8
So evolutionists cannot explain both these lots of similarities by saying
they came from a common ancestor. Either the megabats had a common ancestor with
primates (in which case their similarities to the other bats is not due
to common ancestry) or they had a common ancestor with each other. In which case,
the similarities to primates didn’t come from having the same ancestor. In
each case, the only alternative to common ancestry would be to invoke what is called
‘parallel’ evolution, the belief that the same features just happened
to evolve twice, responding in the same way to the same environmental circumstances,
by ‘luck of the draw’ genetic mistakes (mutations).
Such ‘parallel evolution,’ i.e. evolution repeating itself, causes huge
difficulties for thoughtful evolutionists. Harvard University’s Stephen J.
Gould writes:
‘… the pageant of evolution [is] a staggeringly improbable series of
events … utterly unpredictable and quite unrepeatable … the chance
becomes vanishingly small that anything like [for example] human intelligence would
grace the replay [of this pageant].’9
However, the biblical account of creation can reconcile all this data. The book
of Genesis recounts how each beast was created ‘after
its kind.’ The various families of bats were created as separate
‘kinds.’ The similarities between the megabats and other bats are due
to common design, not common ancestry. The similarities between the visual pathways
of megabats and primates are also because they came from the same designer, not
because they have a common ancestor.
Belief that bats were created just as Genesis recounts is not a blind faith, but
one which is consistent with the evidence.
Interesting facts from the bat-file
- Contrary to mythology, bats do not get entangled in human hair, and are not blind.
- With more than one thousand species, bats make up almost a quarter of all known
mammal species.
- Many bat species are in alarming decline and/or threatened with extinction.
- Many plants are dependent on bats for pollination; other plants benefit from seed
dispersal by bats.10
- The smallest mammal in the world is Thailand’s bumblebee bat; it weighs less
than a 1c coin.11
- The giant flying fox of Indonesia can have a wingspan of nearly 1.8 metres (six
feet).
- The echolocation of fishing bats is able to detect a minnow’s fin, as fine
as a human hair, extending only 2 mm above the water surface. This is because bats
can distinguish ultrasound echoes very close together. Man-made sonar can distinguish
echoes 12 millionths of a second apart, although with ‘a lot of work this
can be cut to 6 millionths to 8 millionths of a second.’12 But bats ‘relatively easily’ distinguish
ultrasound echoes only 2 to 3 millionths of a second apart according to researcher
James Simmons of Brown University.12 This means they can distinguish
objects ‘just 3/10ths of a millimetre apart—about the width of a pen
line on paper.’12
- The free-tailed bats of Mexico can be seen hunting at two miles (more than three
kilometres) in altitude. They can ride tailwinds to fly at more than 100 km/h (60
mph).
- One small brown bat can catch 600 mosquitoes in an hour. The 20 million bats in
the Bracken Cave of Texas eat 250 tons of insects each night. As bat numbers diminish,
the use of chemical insecticides increases.
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References and notes
- The New Encyclopædia Britannica, (15th
Edition) 27:162, 1992. Return to text.
- Creation 9(3):7, 1987. Return to text.
- Ref. 1, 1:952. Return to text.
- Ref. 1, 23:373. Return to text.
- <http://www.ucmp.berkeley.edu/mammal/eutheria/chirfr.html>
29 June 1998. Return to text.
- Gish, Duane T.,
Evolution: The Fossils Still Say NO!, p. 185, Institute For Creation Research,
California, 1995. Return to text.
- Ref. 6, pp. 186–187. Return to text.
- Nature 356(6365):123, 1992. Also,
New Scientist 134(1816):9, 11 April 1992. Return
to text.
- S.J. Gould, Wonderful Life, W.W. Norton & Co, NY and
London, 1989, p. 14 preface, quoted from Origins 17(1):34,
1990. Return to text.
- The New Encyclopædia Britannica, (15th
Edition) 23:374, 1992. Return to text.
- <www.batcon.org>, also many of the unreferenced facts herein
are supported by this site, 2 Sep. 1998. Return to text.
- Simmons was cited in the appropriately titled article: Bats put
technology to shame, Cincinnati Enquirer, 13 October, 1998. His research
paper is, J.A. Simmons et al., Echo-delay resolution in sonar images of
the big brown bat, Eptesicus fuscus, Proceedings of the National Academy
of Science USA, 95(21): 12647–12652, 13
October, 1998. Return to text.
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