A whale of a tale?
by Don Batten
Fossilized bones found in Pakistan are claimed to be those of a ‘walking whale’,1 supposedly an ancestor of today’s
whales. The main claim of Thewissen et al. is that this was a walking
whale. That is, had hind limbs which functioned as legs on land and paddles/flippers
in water.
The skeleton is incomplete, with critical parts missing. It is also highly fragmented.
To establish hind leg function it is necessary to have the pelvic girdle to demonstrate
that the leg bones (femur and small proximal piece of tibia) belong to the rest
of the skeleton and to determine muscle attachments. The pelvic girdle is missing!
With the forelimbs, the humerus and scapula are missing which are again crucial
to interpreting function, as well as establishing connectedness to the skeleton.
Prothero et al.2 suggest five features
to unite whales:
- All incisors parallel with the tooth row—not preserved in Ambulocetus
- Medial lambdoidal crest semicircular—not preserved in Ambulocetus
- Nasals retracted—rostrum (snout) not preserved in Ambulocetus
- Protocones small (features of teeth)
- Accessory cusps large (features of teeth)
Thewissen et al. use their own list of purported whale characters to establish
Ambulocetus as a whale, but as Berta3
points out, some of these characters may have a broader distribution than whales.
Thewissen et al. use a phylogenetic definition of a whale. That is, they
assume common ancestry (evolution) and so justify including the supposed ancestor
with the whales, choosing characters which were common as their criteria. In the
footnotes, the authors mention one major difference viz. ‘Unlike most other
archeocetes, the pterygoid processes are enormous …’, but
there are many big differences, including the degree of variation and specialization
of vertebrae.
A major characteristic of whales is the horizontal tail flukes. Involvement of the
tail in swimming requires strong caudal vertebrae with large processes for muscle
attachment. Thewissen et al. show one ‘caudal’ vertebra
which has almost no processes for muscle attachment. Furthermore, this one caudal
vertebra was not even found with the rest of the skeleton, being ‘referred
material’, found 5 metres above. In other words, the whole of the lumbar,
pelvic and caudal parts of Ambulocetus were ‘constructed’ from
just one lumbar vertebra, one femur, a small piece of tibia (no fibula, no pelvis),
a small piece of the ball of the ankle joint and a few foot and toe bones. And yet
a detailed description is given of how the animal moved in water and on
land! The robust femur and presence of a hoof suggest that Ambulocetus
was a land-dwelling creature.
1. Reconstruction of Ambulocetus, ‘at the end of the power stroke
during swimming’, by Thewissen et al.
2. The stippled bones were all that were found. And the bones coloured red were
found 5 m above the rest. With the ‘additions’ removed there really
isn’t much left of Ambulocetus!
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The paper was received by Science journal on 28 October, 1993 and accepted
on 3 December, 1993, indicating that the paper passed the refereeing process with
no, or only minor, changes being required before publication, and yet the paper
is full of highly conjectural material. The reconstruction of the skeleton assumes
it is a ‘whale’. The authors said, ‘Little is known about
the tail, but there are always many caudal vertebrae in primitive cetaceans and
their relatives’ and so they sketched in a long tail for Ambulocetus!
There are several paragraphs of conjecture about locomotion on land and in water
and yet there is not even a pelvis or any associated vertebrae! The movement of
the forelimbs is also presented in detail and yet there is no humerus or scapula!
If a paper of this quality was submitted for publication in an empirical field of
science such as molecular genetics it would be rejected outright. Why then was this
accepted so readily? It’s probably an indication of the status of paleontology
as a ‘science’ and also the desperate desire of neo-Darwinian evolutionists
to find some fossil evidence of an ‘intermediate’ form to reinforce
belief in gradualism or indeed in evolution itself, as the lay newspapers obligingly
and uncritically report the ‘find’.
The Ambulocetus fossil was found in ‘lower to middle Eocene’
beds. Fossils of whales of the suborder Archeoceti have been found in lower Eocene
strata,4 so Ambulocetus is
unlikely to be an ancestor of modern whales, as claimed by Thewissen et al.
There are too many crucial parts missing to be sure what Ambulocetus is.
Whatever it is, it is unlikely to be a walking ancestor of the whales.
- For updates on Ambulocetus and refutation of critics, see the
Addenda below.
References
- Thewissen, J.G.M., Hussain, S.T. and Arif, M., 1994. Fossil evidence
for the origin of aquatic locomotion in Archeocete whales. Science,
263:210–212. Return to text.
- Prothero, D., Manning, E.M. and Fischer, M., 1988. In: The
Phylogeny and Classification of the Tetrapods, M.J. Benton (ed.), Clarendon,
Oxford, Vol. 2, pp. 201–234. Return to text.
- Berta, A., 1994. What is a whale? Science,263:180–182.
Return to text.
- Encyclopædia Britannica, 15th Edition,
1992, Vol. 23, p. 434. Return to text.
Addendum 1 (1999)
 To
see how so much is made of so little evidence, in the pro-evolution book Teaching
about Evolution and the Nature of Science produced and avidly promoted
by the National Academy of Science, 1998, the sketch at right of Ambulocetus
is used as an illustration of a transitional form. Note the large amount of imagination
involved, including webbed feet. This image is from their website at <http://www.nap.edu/readingroom/books/evolution98/>.
This book has been answered by
Refuting Evolution.
Addendum 2 (4 January 2002)
Some evolutionists have tried to counter this paper by charging me with faking the
information presented.
There is no deceit (faking), or contradiction, in the article. As stated at the
beginning of the article, the article on the web was originally published in Creation
Ex Nihilo Technical Journal (now Journal of Creation)
in 1994, the year Thewissen et al. published their original article. The material
referred to is that published by Thewissen in 1994. It is now claimed, on Thewissen’s
web site, that more material has been found. As far as I am aware, none of this
extra material has been subjected to peer review. That is, it has not been published
in a refereed scientific journal. As such, it is not admissible as scientific evidence
(evolutionists are quick to demand this of creationists). However, even if it is
so published in the future, I don’t have much confidence in the peer review
process when it comes to paleontology—there seems to be a different standard
applied to these papers, compared to experimental (operational) science. So many
false claims have been given credit in prestigious peer-reviewed journals that I
have become rather sceptical of all the claims. For example, Gingerich’s Pakicetus
story, published in the prestigious journal Science in 1983, was based
on some skull fragments. Science even published, on the front cover, an
artist’s reconstruction of the whole creature, with legs becoming
flippers, swimming in the sea chasing fish for its lunch. It is illustrative to
compare this with a more recent reconstruction based on a much more complete skeleton—it
is now clearly a terrestrial creature. See Whale evolution?
Even if the extra Ambulocetus material on Thewissen’s web site is
legitimate, it does nothing to confirm it as a transitional form between whales
and land animals. For example, there is no evidence of the development of the horizontal
tail flukes so characteristic of whales, or the unique hearing system of whales
(i.e. with no opening to the exterior), or the blow-hole, etc., etc. Indeed there
is nothing that is uniquely ‘whale’ that identifies Ambulocetus
as related to whales. Furthermore, the robustness of the femur, and presence of
hooves confirm the creature as a land animal. See
A Whale Fantasy from National Geographic for more [by a Muslim
creationist posted on the Christian creationist True Origins website].
The supposed sequence from land animal to whale is so clear (I speak ironically)
that evolutionists are now contemplating ‘switching horses’ regarding
whale ancestry. Mesonychids were long touted as the ‘sister clade’ of
whales, with fossils being so interpreted (mainly on the basis of ambiguous tooth
and skull characteristics). Now the mesonychids are being questioned as the sister
clade, based largely on molecular comparisons of living animals (Nature
404(6775):235–237, March 16, 2000).
Of course in all this, one has to allow for the immense propensity of paleontologists
for story telling. In a short paper in Nature (395:452,
1998), for example, Thewissen, et al., finished their discussion of whether
or not the mesonychians should be considered a sister group to the whales by saying,
‘in any case, extensive convergence or reversals must have occurred in the
dentition, basicranium and/or tarsus.’ In paleontological jargon, I interpret
this to mean that you can make up any story you like, invoking ‘convergence’
(similarity not due to common ancestry), ‘reversals’, etc., to get the
phylogeny you want. If something does not fit the proposed sequence, then it can
be dismissed as due to convergence, a reversal, etc. Basically, Thewissen is saying,
with a bit of story jigging, they can accomodate the new molecular data. Interestingly,
in this paper Thewissen and co discuss similarities in ankle bones in various extant
and extinct creatures and how this relates to the phylogeny of whales. But the whole
discussion is predicated on the assumption that Pakicetus
and Ambulocetus are in the whale phylogeny—and calling something
a whale—‘cetus’—does not make it a whale!
Luo, in the other paper cited above, said:
‘Both morphological and molecular data are vulnerable to the problem of homoplasies—reversals
to ancestral conditions or parallel changes in different lineages that can camouflage
the true phylogeny …. For example, the ear region of the skull, traditionally
considered to be a good source of highly stable characters, shows some glaring homoplasies
among the ungulates and cetaceans [refs].’
In other words, the supposed whale transition is not at all clear—unlike the
propaganda pronouncements intended for public consumption. TJ 16(1)
will have a thorough analysis
of the supposed phylogeny of whales by
John Woodmorappe. He exposes the extent of the story telling in this
tale of tails (or is it a tale of teeth?).
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