Living Fossils

Neopilina galathea

The search for sea monsters often brings up living fossils, albeit of a more diminutive stature than what its investigators had hoped for. One of these notable expeditions was that of the Galathea mounted between 1950 and 1952 by Anton Bruun “with the serious purpose of testing his theory that such creatures [as sea-serpents] do in fact exist”. While no sea-serpents were seen, they did discover a number of living fossils, such as Neopilina galathea, a primitive mollusk which is neither clam nor snail. While not being the first to discover it, they also found a number of unusually named Vampyrotheuthis infernalis (vampire squid from hell), which is neither octopus nor squid. The belief in, and search for, living fossils is as old as our first encounter with deep sea dredging in the 1800s. Louis Agassiz, commonly known as the pioneer of oceanography and marine biology hoped to find them, as did Darwin’s bulldog, T.H. Huxley. It was thought that the deep sea could have isolated creatures known only in the fossil records so that they were protected from the more successful competitors that were seen as having driven them to extinction.

Even today it is the ocean, and particularly the deep ocean, that predominates in the discussion of living fossils. In a collection on this subject edited by Niles Eldredge and Steven M. Stanley in 1984, twenty-three of the thirty-two articles were on oceanic living fossils. Yet most interesting is the conclusions that these two draw from the discussion, and what these finds mean for the nature of evolution. The very concept of living fossils seems to pose a challenge to the view of a gradual, but ever present, evolutionary push. They tend to be seen as anomalies, and there are a number of competing theories to explain their existence: “Perhaps they lack the requisite genetic variability, or have not yet been subjected to strong […] selection pressure [or] they have been subjected to a straightjacket of unrelenting stabilizing selection” (Living Fossils, 272). Eldredge explains the desire to see these creatures as anomalies by stating that “even the most sophisticated of evolutionists have tended to see evolutionary change as inevitable, given simply the passage of vast stretches of time”. Yet his own analysis avoids confronting the inevitability of evolution altogether.

For Eldredge the existence of living fossils is more an expression of how we tend to classify species, than of what those species actually are. The problem he sees is rather that we tend to look at species as being skin deep. We see that extremely slow rates of evolution “(and, for that matter, all problems of evolutionary rates) are strictly a matter of the transformation of aspects of the phenotype. This is, after all, how we detect the problem in the first place”. What Eldredge suggests is that “speciation […] may be accompanied by a great deal of anatomical, behavioral, and physiological change, or hardly any at all”. The existence of living fossils is merely proof that we need to look into the molecular signs of evolution rather than those which are purely morphological. At the end of his paper he concludes: “no one supposes that it is the actual longevity of a single species that underlies the cases of extraordinarily low-rate lines of morphologic transformation”. From a modern perspective this is the only way he could conclude, for to say otherwise would be to question the inevitability of evolution itself.

Yet it is exceedingly difficult to collect molecular evidence of evolution from the fossil records, to confirm or disprove Eldrege’s conclusion. Rather, it would perhaps be more scientific to say only that the existence of such creatures as Vampyrotheuthis infernalis and its deep sea brethren has, if anything, raised an interesting doubt about the nature and pace of evolutionary change. Up to the modern time molecular biology has increasingly taken centre stage, a move that has only recently received any substantial challenge. Genetics, while concerning itself with biology, is more closely related to physics and engineering than with the naturalists of old, and since Steven Jay Gould their have been few elegant interpreters of evolutionary theory. Many prominent nineteenth-century naturalists stressed that the concept of species was a kind of useful fiction, but if anything, the genetic turn has ignored this kind of detachment. It is assumed that the genetic material is the blueprint of life, everything is there, and since genetic tests can show the range of “normal” variation, they are at liberty to use this to determine speciation.

I am not up on the most recent trends in evolutionary biology and genetics, but an overview of the popular literature on the matter would seem to suggest this position. Sharks and Crocodiles are living fossils, but no one seems to notice, because they are, in a way, normal. They do not seem to exist in the conceptually unsettling in-between, like octopus and squid, or clam and snail. Regardless of how I feel about the logic behind it though, there is something delightfully paradoxical and archaic about the concept of the living fossil; creatures who, even in the deep time of evolutionary history, are worthy of being called old.

Bibliography:

Bryson, Bill. A Short History of Nearly Everything. Canada: Doubleday Canada, 2003.

Eldredge, Neiles and Steven m. Stanley, eds. Living Fossils. New York: Springer-Verlag, 1984.

Ellis, Richard. The Search for the Giant Squid. New York: The Lyons Press, 1998.

Idyll, C.P. Abyss: The Deep Sea and the Creatures That Live in It. New York: Thomas Y.

Crowell Company, 1964.

Ley, W. Scylla Was a Squid. Natural History Magazine. 2007. 25 Feb. 2007.

<http://www.naturalhistorymag.com/editors_pick/1941_06_pick.html>.

Nigg, Joseph ed. The Book of Fabulous Beasts: A Treasury of Writings from Ancient

Times to the Present. Oxford: Oxford University Press, 1999.

Packard, A.S. Jr. Colossal Cuttlefishes. The American Naturalist, vol. 7, No. 2. (Feb.,

1873). <http://links.jstor.org/sici?sici=0003-0147%28187302%297%3A2%3C87%3ACC%3E2.0.CO%3B2-5>.

Rice, Tony. Deep Ocean. London: The Natural History Museum, 2000.

Verrill, A.E. The Colossal Cephalopods of the North Atlantic. II. The American

Naturalist, vol. 9, No. 2. (Feb., 1875).  <http://links.jstor.org/sici?sici=0003-0147%28187502%299%3A2%3678%ATCCOTN%3E2.0.CO%3B2-4>.

Verrill, A. Hyatt. The Ocean and Its Mysteries. New York: Duffield & Co, 1925.

http://en.wikipedia.org/wiki/Living_fossil

http://en.wikipedia.org/wiki/Anton_Bruun

http://en.wikipedia.org/wiki/Crocodile

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