The Panda’s Thumb (23 page)

Two elements dominate this cryptic fauna: brachiopods and Kirkpatrick's coralline sponges. Goreau and Hartman described six species of coralline sponges from the fore-reef slope of Jamaica's reef. These species form the basis for an entire new class of sponges, the Sclerospongiae. In the course of their work, they rediscovered Kirkpatrick's papers and studied his opinion on the relationship between coralline sponges and the enigmatic fossil stromatoporoids and chaetetids. “Kirkpatrick's comments,” they write, “have led us to compare the coralline sponges described above with representatives of several groups of organisms known from the fossil record.” They have shown, quite convincingly I think, that these fossils are indeed sponges. A major zoological discovery has solved an outstanding problem in paleontology. And crazy old Randolph Kirkpatrick had known it all along.

When I wrote to Hartman to inquire about Kirkpatrick, he cautioned me not to judge the man too harshly on his nummulosphere, for his taxonomic work on sponges had been sound. But I respect Kirkpatrick both for his sponges and for his numinous nummulosphere. It is easy to dismiss a crazy theory with laughter that debars any attempt to understand a man's motivation—and the nummulosphere is a crazy theory. I find that few men of imagination are not worth my attention. Their ideas may be wrong, even foolish, but their methods often repay a close study. Few honest passions are not based upon some valid perception of unity or some anomaly worthy of note. The different drummer often beats a fruitful tempo.

WHEN
T
HOMAS
H
ENRY
Huxley lost his young son, “our delight and our joy,” to scarlet fever, Charles Kingsley tried to console him with a long peroration on the soul's immortality. Huxley, who invented the word “agnostic” to describe his own feelings, thanked Kingsley for his concern, but rejected the proferred comfort for want of evidence. In a famous passage, since taken by many scientists as a motto for proper action, he wrote: “My business is to teach my aspirations to conform themselves to fact, not to try and make facts harmonize with my aspirations…. Sit down before fact as a little child, be prepared to give up every preconceived notion, follow humbly wherever and to whatever abysses nature leads, or you shall learn nothing.” Huxley's sentiments were noble, his grief affecting. But Huxley did not follow his own dictum, and no creative scientist ever has.

Great thinkers are never passive before facts. They ask questions of nature; they do not follow her humbly. They have hopes and hunches, and they try hard to construct the world in their light. Hence, great thinkers also make great errors.

Biologists have written a long and special chapter in the catalog of major mistakes—imaginary animals that should exist in theory. Voltaire spoke truly when he quipped: “If God did not exist, it would be necessary to invent him.” Two related and intersecting chimeras arose during the early days of evolutionary theory—two animals that should have been, by Darwin's criteria, but were not. One of them had Thomas Henry Huxley for a godfather.

For most creationists, the gap between living and nonliving posed no particular problem. God had simply made the living, fully distinct and more advanced than the rocks and chemicals. Evolutionists sought to close all the gaps. Ernst Haeckel, Darwin's chief defender in Germany and surely the most speculative and imaginative of early evolutionists, constructed hypothetical organisms to span all the spaces. The lowly amoeba could not serve as a model of the earliest life, for its internal differentiation into nucleus and cytoplasm indicated a large advance from primal formlessness. Thus Haeckel proposed a lowlier organism composed only of unorganized protoplasm, the Monera. (In a way, he was right. We use his name today for the kingdom of bacteria and blue green algae, organisms without nucleus or mitochondria—although scarcely formless in Haeckel's sense.)

Haeckel defined his moneran as “an entirely homogeneous and structureless substance, a living particle of albumin, capable of nourishment and reproduction.” He proposed the moneran as an intermediate form between non-living and living. He hoped that it would solve the vexing question of life's origin from the inorganic, for no problem seemed thornier for evolutionists and no issue attracted more rear-guard support for creationism than the apparent gap between the most complex chemicals and the simplest organisms. Haeckel wrote: “Every true cell already shows a division into two different parts, i.e., nucleus and plasm. The immediate production of such an object from spontaneous generation is obviously only conceivable with difficulty; but it is much easier to conceive of the production of an entirely homogeneous, organic substance, such as the structureless albumin body of the Monera.”

During the 1860s, the identification of monerans assumed high priority on the agenda of Darwin's champions. And the more structureless and diffuse the moneran, the better. Huxley had told Kingsley that he would follow facts into a metaphorical abyss. But when he examined a true abyss in 1868, his hopes and expectations guided his observations. He studied some mud samples dredged from the sea bottom northwest of Ireland ten years before. He observed an inchoate, gelatinous substance in the samples. Embedded in it were tiny, circular, calcareous plates called coccoliths. Huxley identified his jelly as the heralded, formless moneran and the coccoliths as its primordial skeleton. (We now know that coccoliths are fragments of algal skeletons, which sink to the ocean bottom following the death of their planktonic producers.) Honoring Haeckel's prediction, he named it
Bathybius Haeckelii
. “I hope that you will not be ashamed of your godchild,” he wrote to Haeckel. Haeckel replied that he was “very proud,” and ended his note with a rallying cry: “Viva Monera.”

Since nothing is quite so convincing as an anticipated discovery,
Bathybius
began to crop up everywhere. Sir Charles Wyville Thomson dredged a sample from the depths of the Atlantic and wrote: “The mud was actually alive; it stuck together in lumps, as if there were white of egg mixed with it; and the glairy mass proved, under the microscope, to be a living sarcode. Prof. Huxley…calls it
Bathybius
.” (The Sarcodina are a group of single-celled protozoans.) Haeckel, following his usual penchant, soon generalized and imagined that the entire ocean floor (below 5,000 feet) lay covered with a pulsating film of living
Bathybius
, the
Urschleim
(original slime) of the romantic nature philosophers (Goethe was one) idolized by Haeckel during his youth. Huxley, departing from his usual sobriety, delivered a speech in 1870 and proclaimed: “The
Bathybius
formed a living scum or film on the seabed, extending over thousands upon thousands of square miles…it probably forms one continuous scum of living matter girding the whole surface of the earth.”

Having reached its limits of extension in space,
Bathybius
oozed out to conquer the only realm left—time. And here it met our second chimera.

Eozoon canadense
, the dawn animal of Canada, was another organism whose time had come. The fossil record had caused Darwin more grief than joy. Nothing distressed him more than the Cambrian explosion, the coincident appearance of almost all complex organic designs, not near the beginning of the earth's history, but more than five-sixths of the way through it. His opponents interpreted this event as the moment of creation, for not a single trace of Precambrian life had been discovered when Darwin wrote the
Origin of Species
. (We now have an extensive record of monerans from these early rocks, see essay 21.) Nothing could have been more welcome than a Precambrian organism, the simpler and more formless the better.

In 1858, a collector for the Geological Survey of Canada found some curious specimens among the world's oldest rocks. They were made of thin, concentric layers, alternating between serpentine (a silicate) and calcium carbonate. Sir William Logan, director of the Survey, thought that they might be fossils and displayed them to various scientists, receiving in return little encouragement for his views.

Logan found some better specimens near Ottawa in 1864, and brought them to Canada's leading paleontologist, J. William Dawson, principal of McGill University. Dawson found “organic” structures, including a system of canals, in the calcite. He identified the concentric layering as the skeleton of a giant foraminifer, more diffusely formed but hundreds of times larger than any modern relative. He named it
Eozoon canadense
, the Canadian dawn animal.

Darwin was delighted.
Eozoon
entered the fourth edition of the
Origin of Species
with Darwin's firm blessing: “It is impossible to feel any doubt regarding its organic nature.” (Ironically, Dawson himself was a staunch creationist, probably the last prominent holdout against evolution. As late as 1897, he wrote
Relics of Primeval Life
, a book about
Eozoon
. In it he argues that the persistence of simple Foraminifera throughout geologic time disproves natural selection since any struggle for existence would replace such lowly creatures with something more exalted.)

Bathybius
and
Eozoon
were destined for union. They shared the desired property of diffuse formlessness and differed only in
Eozoon
's, discrete skeleton. Either
Eozoon
had lost its shell to become
Bathybius
or the two primordial creatures were closely related as exemplars of organic simplicity. The great physiologist W. B. Carpenter, a champion of both creatures, wrote:

Here was a vision to titillate any evolutionist! The anticipated, formless organic matter had been found, and it extended throughout time and space to cover the floor of the mysterious and primal ocean bottom.

Before I chronicle the downfall of both creatures, I want to identify a bias that lay unstated and undefended in all the primary literature. All participants in the debate accepted without question the “obvious” truth that the most primitive life would be homogeneous and formless, diffuse and inchoate.

Carpenter wrote that
Bathybius
was “a type even lower,
because less definite
, than that of Sponges.” Haeckel declared that “protoplasm exists here in its simplest and earliest form, i.e., it has scarcely any definite form, and is scarcely individualized.” According to Huxley, life without the internal complexity of a nucleus proved that organization arose from indefinite vitality, not vice versa:
Bathybius
“proves the absence of any mysterious power in nuclei, and shows that life is a property of the molecules of living matter, and that organization is the result of life, not life the result of organization.”

But why, when we begin to think about it, should we equate formless with primitive? Modern organisms encourage no such view. Viruses are scarcely matched for regularity and repetition of form. The simplest bacteria have definite shapes. The taxonomic group that houses the amoeba, that prototype of slithering disorganization, also accommodates the Radiolaria, the most beautiful and most complexly sculpted of all regular organisms. DNA is a miracle of organization; Watson and Crick elucidated its structure by building an accurate Tinkertoy model and making sure that all the pieces fit. I would not assert any mystical Pythagorean notion that regular form underlies all organization, but I would argue that the equation of primitive with formless has roots in the outdated progressivist metaphor that views organic history as a ladder leading inexorably through all the stages of complexity from nothingness to our own noble form. Good for the ego to be sure, but not a very good outline of our world.

In any case, neither
Bathybius
nor
Eozoon
outlived Queen Victoria. The same Sir Charles Wyville Thomson who had spoken so glowingly of
Bathybius
as a “glairy mass…actually alive” later became chief scientist of the
Challenger
expedition during the 1870s, the most famous of all scientific voyages to explore the world's oceans. The
Challenger
scientists tried again and again to find
Bathybius
in fresh samples of deep-sea mud, but with no success.

When scientists stored mud samples for later analysis, they traditionally added alcohol to preserve organic material. Huxley's original
Bathybius
had been found in samples stored with alcohol for more than a decade. One member of the
Challenger
expedition noticed that
Bathybius
appeared whenever he added alcohol to a fresh sample. The expedition's chemist then analyzed
Bathybius
and found it to be no more than a colloidal precipitate of calcium sulfate, a product of the reaction of mud with alcohol. Thomson wrote to Huxley, and Huxley—without complaining—ate crow (or ate leeks, as he put it). Haeckel, as expected, proved more stubborn, but
Bathybius
quietly faded away.

Eozoon
hung on longer. Dawson defended it literally to the death in some of the most acerbic comments ever written by a scientist. Of one German critic, he remarked in 1897: “Mobius, I have no doubt, did his best from his special and limited point of view; but it was a crime which science should not readily pardon or forget, on the part of editors of the German periodical, to publish and illustrate as scientific material a paper which was so very far from being either fair or adequate.” Dawson, by that time, was a lonely holdout (although Kirkpatrick of essay 22 revived
Eozoon
in a more bizarre form later). All scientists had agreed that
Eozoon
was inorganic—a metamorphic product of heat and pressure. Indeed, it had only been found in highly metamorphosed rock, a singularly inauspicious place to find a fossil. If any more proof had been needed, the discovery of
Eozoon
in blocks of limestone ejected from Mount Vesuvius settled the issue in 1894.