Figure 4.3: The chaperone wall of a Pteridinium specimen stepping up from a lower bedding plane surface to a higher. Height of chaperone wall 16 mm.
Namibian?"—at which point his eyes got teary and he replied, "Don't start with me on that!"
Seilacher thought that Bushmen have curious, compressed features with high cheekbones and a narrow lower jaw, a fetal face. He attributed the latter to neoteny. I replied that at some point bushmen women must have preferred such a face.
Because the upcoming dance is held only every 3 months, we expected a whole community affair. We soon learned that the dance and food (white bread-and-butter sandwiches,19 pancakes rolled around a nut butter, and meat stew on rice with hot chutney) were for whites only. This was the first instance of discrimination any of us had encountered in Namibia. Whites seemed like Americans or Europeans physically, but I sensed a great cultural graben separating us from them. Handsome young men danced with an older lady, who was a cook for laborers. When the music began, Seilacher started up and danced with the hotel/bar manager, a rotund lady with a pleasant English accent. Frieder immediately took a dance with Edith Seilacher, and I danced with her myself later.
Frieder and I quietly nicknamed an older, ruddy-complected blond man in the crowd Socrates, on account of what we felt was his Grecian profile, where his downward directed nose approached his upward-directed chin. This man danced up a storm with the ladies, waltzing, jiving, anything. Frieder and I joked to ourselves, "I hope Socrates doesn't order the wrong drink!"
A half-breed Bushman stood outside the door to the dance hall with a hangdog look on his face. Later he came in to bus tables. The live music band consisted of a man on keyboard and another playing an intricate but slow tempo electric guitar lead. No vocals.
The morning of July 31 we returned to the Schutztruppe stable locality, intent on finding and excavating a large slab of quartzite bearing the Pteridinium fossils. We tried at first to excavate a low ledge where we had found the three-dimensional fossils yesterday, but we had no success; the more we excavated the low ledge, the less likely it seemed that we were going to find more fossils. So we left the exposed specimens intact and put back the large blocks we had pried out with the 167-cm pry bar. I spotted between the rocks a plant rootlet fuzzy with mycorrhizal fungi.
After a lunch of Windhoek bread, peanut butter, dry and moist sausage, pears, apples, and oranges, I trekked to the east of the locality and tried to follow the fossiliferous bed along strike. I saw some decimeter-sized flute cast-like bedding structures in the sandstone, and abundant rounded mud chips. Next I came upon an amphitheater-shaped depression in the bedrock, with a spring in the bottom of the depression. Sparrowlike birds were diving for cover whenever I moved, but they returned to sipping water and snatching flies when I sat down. I hiked past the amphitheater and thought about the prospect of being stalked by a leopard near this water source. Farmers in the area drive cheetahs and leopards into traps stretched across wind gaps. Cheetahs are bagged (literally) and sold alive. Leopards, more dangerous, are killed. Both species are endangered.
I headed back toward the rest of the field party and found several Cloudina specimens in a buff-colored limestone bed. The Schwartz-rand Limestone is limy, as I confirmed with the hydrochloric acid fizz test. I came across a jumping spider and a giant cricket with harvest-manlike legs.
As I returned to my colleagues, Seilacher called out "Mark, we found it!" The party was preparing to excavate beds exposed near the head of a shallow wash approximately 150 m from the Schutztruppe stables, where the van was parked. At this new site, Pteridiniums were spread out on the rocks over a distance of about 10-15 m, and the blocks could be easily lifted. Lithops erniana lives in rock crevices nearby, with some specimens living in fairly deep crevices where direct sunlight lasts only an hour or so. By 4:00 p.m. a series of rectangular subslabs had been removed, and Hans began, with the help of all, to glue the slabs together with an amazingly strong, pastelike achemie glue. Casting would be difficult because the fossiliferous slab was broken up into multiple blocks that had to be aligned properly in order to make a faithful cast.
Occurring as float20 fragments near these blocks are orboid "flying saucers" 1 cm in diameter. We could not find any in matrix but the float source is clearly local bedrock. Seilacher called them Protolyellia, an organism now added to the diversity list of Pteridinium and Namalia, a simple discoidal form composed of sand.21
During the driving this day I learned how Seilacher's older brother was a radio operator in a Nazi bomber aircraft Heinkel HE-111. He crashed the plane twice. He was interested in becoming a physician, but died on the Russian front. Dolf never flew in the war but wanted to fly with his brother. Dolf was not excited by the HE-111 but he would have liked to dive in a Stuka dive bomber.
Dolf also told the story about almost being bitten by a horned viper in southeast Egypt. While peering into crevices trying to see the founder colony of an extensive fossil oyster bed, he spotted the coiled snake, poised to strike and only inches away from his hand. Had he been bitten, there would have been about enough time to smoke one cigarette.
On August 1 we again visited Hellmut Erni and were joined by Dolf and Edith's friends Manfred and Catherine. Erni directed us to a small shed adjacent to the dusty Karakul sheep quarters. Inside this shed is a wonder of Ediacaran treasures, Erni's storehouse of fossils, a mecca for paleontologists interested in Ediacarans. Included in the collection are such things as large scorpions preserved in jars of alcohol. Seilacher and I took photographs of Erni's Pteridiniums, Namalias, Rangeas, and regular and "elephant's foot" forms of the Erniettas. Shepherds on foot, we are told, were first to find the Rangea specimens.
Later in the day we reached the Aar site. At 12:40 Seilacher began to give the grand tour; having already heard the presentation, I set off in a general southerly direction to study the stratigraphy of the Schwartzrand Limestone. The Schwartzrand Kalk (Black Rim Limestone) is a prominent unit in the Nama Group and, as its name indicates, forms a dark colored rim on the low hills and canyon walls of the region. The Aar plateau, which we explored later, is capped by an expanse of dark bluish gray limestone. From my field notes for August 1 is an informally paced (my pace is 0.9 meters per step) stratigraphic section:
61 [paces] Schwartzrand Black Rim: dark gray limestone intraclast conglomerate
17 Buff ledge wl.Epiphyton 12 Thin buff ledge
26 Buff-red-blackish, striped buff and dark gray
33 Buff gray wlblackish desert varnish in layers
53 Gray to buff with iron-rich swirls, nodular wl Epiphyton
37 Thin yellow buff unit wlscattered iron nodules
66 Calcareous sandstone wlrounded mud chip horizons; thin-
bedded to massive sandstone to quartzite, friable in places with Pteridinium and Protolyellia; casting site
This day we made a trip to the central portion of the Aar Plateau to view petroglyphs on the top of the plateau. We rode out to the site in the back of Hellmut Erni's truck, a Nissan Hi Rider 1 Tonner 2500 diesel. Erni had a box of Courtleigh Satin Leaf cigarettes on the dashboard.
Bushmen and their ancestors formed the petroglyph art by impacting the smooth surfaces of the plateau-capping Schwartzrand Limestone with pointed rocks. Each hit made a white dot on the dark gray limestone, and images were formed by a series of closely spaced dots. Judging from the weathering on the outcrop, some of the images must date back thousands of years. The quality of some of the art is outstanding, comparable to Las-caux or Altamira cave art. Not all of the images are ancient; one, with much less weathered white impact dots, bears the date 9/9/1927. Thus, this appears to be the oldest continuing art series.
Bold images of rhinoceros, giraffe, eland antelope, oryx, snake, mountain zebra, and elephant are scattered over the plateau surface. Some of the animal images have somewhat distorted proportions. Many of these creatures no longer live in this region. One image looks like a tunafish or a penguin swimming at full speed. Human figures are less common, but one shows a female figure with large breasts lying on her back. A male figure, with an erect penis, is running away from her. Does this depict an ancient rape scene? A petroglyph of a male authority figure (the chief?) extends his right arm forward in an apparent pose of benediction. Under his outstretched hand is a petroglyph of a wheel with eight spokes.
At an overhanging ledge nearby we viewed delicate paintings in red pigment of human figures. The earliest examples of this type of Namibian rock art date back 19,000—26,000 years. The geometric patterns are believed to have been inspired by hallucinatory experiences. Much of what we know about Namibian rock art comes from a group of !Xam San men imprisoned in Cape Town for livestock theft, murder, and other crimes.22 German philologist Wilhelm H. I. Bleek acquired custody of the men. The men worked as Bleek's domestic servants, living in huts in his garden. They supplied Bleek and his sister-in-law, Lucy C. Lloyd, with tales of their !Xam tradition.
Bleek focused on the men's language, whereas Lloyd transcribed approximately 10,000 pages of !Xam folklore and myth.23 Some of the rock art images, originally interpreted as scenes of the hunt, are now, in the light of Bleek and Lloyd's work, viewed as portraying a rainmaking ritual. In this important ritual, the !Xam saw the rain cloud as a giant lobopodlike animal, striding across the parched land with billowy legs of streaming rain. The task of the rainmaker was to entice this giant creature from its waterhole lair, lead it to high ground, and then slaughter it. The falling rain represented the blood shed by the slain rain creature. The rain creatures depicted in the rock art are always large herbivores (hippopotamus, antelope) but usually show strange proportions and features.24 So in a sense, the original interpretation of the scenes as the hunt is correct, with the quarry being life-giving rain.
The Schwartzrand Limestone here is packed with Cloudina fossils, most of the shells here having been moved and broken by currents and redeposited as thick coquinas (lithified shell hash). A large boulder of limestone sits atop the plateau. When struck it rings like a deep-throated brass bell.
Dropping off the plateau into a nearby desert wash, punctuated by deep pools favored by game, we found mistletoe growing up and out of the trunk of an acacia tree. The tissue of the mistletoe permeates the entire acacia. Erni related how many acacia trees on his land have been killed by mistletoe.
The next day (August 2) I continued my exploration of the Schwartz-rand Limestone as work at the casting site continued. I continued hiking south of the stone marker of the day before. In a piece of Schwartzrand float (1 of 8/2/93) within 200 m of the casting site, I found probable cloudinids in living position. I hiked to the Schwartzrand Cliffs to the northeast of the casting site. Here I came across evidence of ancient human habitation.
Our hominid lineage has a long history in this part of the world. In 1992 a group including geologist John Van Couvering found a 13-mil-lion-year-old jaw from Otavipithecus, the ancestor common to apes and humans, in Namibian strata. The fossil is the first evidence of such an ancestor south of the Equator. The lower jaw is about 3 in. long, and its teeth resemble those of humans and apes rather than those of monkeys. The oldest known fossil specimens belonging to Homo sapiens occur in caves in South Africa in deposits only 120,000 years old.25 So it was with great interest that I examined these cliff shelter dwellings.
The shelters were formed by a semicircle of stones built against the Schwartzrand cliff. The shelters faced west, perhaps to give the inhabitants light later in the evening. They were safe from predators here and had the natural amphitheater with a spring nearby. Like tract housing, the shelters were spaced about 100 m apart along the cliff face. White quartz and chert flakes in the center of the stone semicircles indicated that the dwelling builders were a Paleolithic people. At one point the cliff was overhanging, providing a particularly nice shelter. Ostrich egg fragments were scattered amid the knapped white quartz flakes.
That night, Bruce Runnegar (his name is Old Norse for "rye field") of the University of California at Los Angeles and Jim Gehling of the University of South Australia arrived in a white Volkswagen minivan nearly identical to ours. The next morning (August 3) we set out to the Aar locality to do the casting.
En route, as in earlier days, we encountered a family of ostriches. Mother, father, and six youngsters watched us warily from a distance. On average, five of the six juveniles would be taken by jackals before they reached maturity. Every day we saw the ostrich family in the same place.
Large birds have a long history in Namibia. A joint Franco-Namibian expedition announced in the December 1995 issue of La Recherche the discovery in the Namib desert of a 17-million-year-old giant egg. The egg was discovered by Brigitte Senut of the National Museum of Natural History in Paris. She found the egg, nearly intact, partly embedded in sandstone, and called it "one of the miracles of fossilization."
The egg had a volume of 1.7 L, as compared with the 1.2-L volume of the average ostrich egg, and a shell twice as thick as ostrich eggshell. The early Miocene egg, along with bones of early rodents, antelope, and an elephant-like proboscidian, were discovered in the Sperrgebiet ("forbidden zone"), until recently the exclusive preserve of diamond miners. Senut and her colleagues considered the possibility that the egg belonged to a large turtle, but the calcitic composition of the shell links it to the shells of other birds.
The egg has been attributed to "Namibia's ancient big bird."26 However, no one knows how big this bird was or what it looked like. The species was nevertheless given the name Diamantornis wardi (Ward's diamond bird), to honor South African geologist John Ward. Ward studied ancient dunes of the region.
With Runnegar and Gehling, colleagues from the Namibian Geological Survey, and C. K. "Bob" Brain of the Transvaal Museum in our company, we were in high spirits driving to the field site. I asked Jim Gehling, "What would happen if a holistic thinker were to meet up with a reductionist?" Jim replied, "Annihilation!" Seilacher was in one of those moods that induces him to start telling self-effacing Swabian jokes. The Swabians are a tribe from the Swabian region of Germany to whom Dolf owes allegiance.
A Swabian mountain climber in the Alps is beset by a tremendous avalanche. After hours of frantic effort the rescue team finally digs him out. On coming to and seeing the uniforms of the Swiss Red Cross, the Swabian declares, "I gave at the office!"
At the site I took Jim and Bruce to the stone ring shelters. We examined sedimentary structures of the Schwartzrand, and noted thrombo-lites27 in the buff-colored carbonate rocks below the Schwartzrand. A desert roach crawled across a rock.
Seilacher began with an exposition of his hypothesis of Pteridinium reproduction. He noted that there are forms living in different levels in the sediment, that the ones in the higher levels are the progeny, and that the edge of the side wall of the older generation "coincides exactly with the median line of the next generation." Runnegar asked whether the geometric arrangement could be mere coincidence and whether multiple examples of this relationship were known. Seilacher replied that yes, there were several examples, and that in this place the specimens were oriented in the same direction as the ancient water currents of the locale. Gehling asked whether this inference was checked with measurements of cross-bedding (a way to determine ancient current direction) in strata higher up in the stratigraphic section. I replied yes, they had been checked.
But because the fossils under immediate scrutiny were, under Seilacher's interpretation, buried in life, they would not have felt the current directly. Seilacher infers that the orientation of the Pteridiniums was in response to currents in pore water induced by water flow above the sediment surface. Furthermore, the next generation, growing as a bud along the edge of the outside wall of the parent, would develop in parallel to the orientation of the parent generation. Gehling then noted that some of the progeny Pteridiniums were oriented at 90 degrees to the adults. Seilacher replied that the grooves of the Pteridinium (at right angles to the axis) might also be able to align with current. In any case, in his view the orientation of the Pteridiniums was not caused by mechanical current transport and deposition of the bodies. Gehling seemed skeptical about this idea.
Runnegar noted that he was trying to make similar inferences regarding a slab bearing Australian Phyllozoon fossils, currently under assembly for transport to a museum. I replied that these Pteridinium slab specimens were to remain in Namibia, and that we were going to return with only a silicon mold of the slab specimens. Seilacher added that the actual specimens would remain on Erni's farm, and that Erni would be mighty proud of them.
Runnegar was asked whether he had a compass orientation on the Australian Phyllozoon slab. He replied that he did not. The fragments of the slab were transported by helicopter and assembled in his laboratory. Seilacher replied that, without the advantage of helicopter time in Namibia, his team was able to get an orientation on the Pteridinium slab. At this comment everyone broke out in laughter.
Seilacher later described the morphology of Pteridinium as a bathtub for unmarried couples, consisting of two troughlike bathtubs on either side, with a "chaperone wall" between, effectively separating the "couple."
Later I pointed out a Pteridinium specimen with an interesting profile. One bathtub wall rose steeply, and the other flattened out. Seilacher replied that this was commonly seen, with the bathtub wall flattening out like a ray's wing. I agreed that it was indeed much like a ray's wing, complete with the upturned fold right at the edge. Seilacher noted that he takes this kind of information very seriously because it provides three-dimensional detail.
Hans Luginsland skillfully guided the hands of the field party as they nestled the glued-together slab into a bed of sand near where the blocks were quarried. Hans mixed up the batch of silicon, combining the whipped-cream white silicon body with the navy blue liquid catalyst. The mixture smells like spackling. He carefully applied it to the base of the inverted sandstone bed, working the sky-blue material into every fold and flute of the fossils and every crevice of the rock, ensuring that no air bubbles had formed. It was very much like frosting a cake, and Hans used a pastry brush. This led to a discussion of German bakers and German bread. Seilacher noted that authentic German bread is available in New Haven, Connecticut, but must be flown in from Canada and costs $7-8 a pound. When Hans's work was completed, all that remained was to wait for the curing of the silicon mold.
We had had rain recently, and unfortunately that night proved to be unusually cold. Although this was the desert in a generally warm region, it was nevertheless the austral winter. The silicon was not designed to cure at freezing temperatures, and the cold not only stopped the curing process but ruined the silicon so that it would not cure at all. This disastrous state of affairs was not discovered until the next morning.
On August 4 Hans was in a state of high agitation. His first attempt at casting, the main object of the expedition, had been ruined by an unexpected frost. What to do next was not clear. Jim Gehling recounted how he had attempted to make a mold of an important Ediacaran fossil in Australia, one still attached to bedrock. Something had gone wrong with the molding medium, which turned to an inflexible, immovable glue and remains attached to this key specimen to this day.
Much discussion was spent on what to do with the Pteridinium slab, covered with slimy, ruined silicon. Finally it was agreed to build a wind shelter to help keep the rock warm, scrape off the old layer (a messy and laborious process), and apply the next layer with a more than ample charge of catalyst. Fortunately, the Seilacher team had brought along extra silicon for just such a contingency. The new silicon layer was applied where the old had been, and we all hoped for the best.
The day of the silicon problem I traveled with Gehling, Runnegar, Friedrich "Frieder" Pfluger (Seilacher's graduate student), and Brain. Our object for the day was to relocate the type locality of Ernietta plateauensis. We pulled off of a paved road near a farm windmill and what appeared from a distance to be an anticline. As we hiked in to the locality, we were excited to find a black chert. Black cherts sometimes harbor exquisitely preserved microfossils, but later work showed this layer to be unpromising because it had recrystallized, obliterating any fossils that might have been present.28
As we approached the Ernietta plateauensis—type locality on foot, Pflug's point C in his 1966 paper,29 we encountered a troop of baboons. The alpha males challenged us from across the canyon, and we traded calls with them for several minutes. It was the first time I had ever attempted to communicate with another primate species in the wild. Apparently they got the message, for they left us alone for the rest of the day.
While hiking we regaled one another with earthy field stories and were subjected to Bruce Runnegar's particularly acrid sense of humor. Someone suggested expanding Namibia's culinary spectrum by opening a specialty shop for sheep-dung-maggot shish kebabs.
We hiked into a small canyon and over to find a fault contact between the quartzite and limestone. Soon we reached the ledge marking the contact between the Daris and the carbonate rocks, and realized that this must be Pflug's point C. Brain took a photo (figure 4.4) of three of us
(me, Bruce, and Jim) on the site. We found no erniettids, but I did find two Pteridinium specimens. The first (2 of 8/4/94) was a nice three-dimensional piece with vertical chaperone wall intact. The second was poorly preserved but showed paired bathtub walls. Both were preserved in sandstone. This is apparently a new Pteridinium locality.
Bruce Runnegar tried to talk me out of the first specimen, for he correctly realized it to be a specimen of potential importance. I politely refused, saying that perhaps we could talk about it later.
Next we drove to the Kuibis area. There we met a Mr. Loots and asked him for permission to go to the Rangea schneiderhoehni type locality. He told us that the land was owned by a Mr. Blow and was called the Aukam property. We located a narrow quartzite ridge near a railroad track and the edge of the Loots property. We hiked up to the trig station (tall aerial and solar panels) and over the hill but found no fossils. The glaring white quartzite crops out only irregularly here; the rest is a jumble of rounded boulders. We headed back and stopped just past the north end of the ridge. Getting out of the van, I found a poorly pre-
Figure 4.4: From left to right, the author, B. Runnegar, and J. G. Gehling in the field in Namibia in August 1993. The Schwartzrand (Black Rim) Limestone is visible in the background.
Figure 4.4: From left to right, the author, B. Runnegar, and J. G. Gehling in the field in Namibia in August 1993. The Schwartzrand (Black Rim) Limestone is visible in the background.
served Pteridinium. Runnegar was particularly pleased with this; at least we could confirm that fossils occur at this site. Now we knew that Pteridinium co-occurs at the type localities of both Ernietta plateauensis and Rangea schneiderhoehni.
We returned to the Bahnhof Hotel, and I was feeling quite pleased with myself on account of the day's discoveries. The small living room of the hotel had a fireplace, and as we gathered around for evening drinks we began the Ediacaran debate. This had been planned by Seilacher to be largely a debate over the validity of his Vendobionta theory, with Runnegar playing the role of devil's advocate. Seilacher had it set to be a contest between the reductionist and the holistic points of view.
Seilacher began by asking whether we all agreed that life of the Vendian is a phenomenon all its own—not merely an extension of the Cambrian world, but a phenomenon unto its own self, with a unique character throughout the world. Runnegar affirmed that all present were in agreement with that view, but then he refined the question by asking whether the Ediacarans were monophyletic, that is, members of the same group of related organisms. Seilacher agreed that, if so, this would make the Ediacarans even more unique. Runnegar then asked whether the organisms were similar because they were responding to similar environmental circumstances of the time rather than all being closely related. Seilacher replied that it was necessary to make exceptions to the Vendobionta scheme right away. Nevertheless, it was his preference, as far as possible, to treat them as all part of the same group. This would be in contrast to other paleontologists who would consider each form separately, suggesting that Dickinsonia resembles a fungiid coral and ignoring the rest of the Ediacarans.30
Seilacher's main exceptions would involve Vendian organisms that do not fit his Vendobionta model. For example, in Newfoundland there are specimens of unequivocal Vendobionts (such as frond fossils), but there are also forms variously and informally called lion's feet, dog's feet, and so forth. These forms are merely roundish globs, or globs within a glob, so under the traditional phyloge-netic scheme they become assigned to the jellyfish group. Thus, the traditionalists have a ready explanation for everything.
Seilacher continued by noting that the glob forms do have a morphology, but it is a morphology of "dumplings in a plastic bag." He would not include such things among the quilted Vendobionts. Similarly, the large pogonophoran-like tube worms fossils from Ediacara, Australia,31 would not be part of Vendobionta.
Runnegar asked whether the sand corals and trace fossils would also have to be excluded. Seilacher replied that those are different, that body fossils were currently under discussion, and that sand corals were in a different class altogether. Seilacher then reminded Runnegar that the Vendobionta concept includes not only the unique body construction of the Ediacarans but also their unique preservation. Runnegar objected that he would not wish to include Tribrachidium and
Spriggina along with the other Ediacaran body fossils. He continued by saying that it might be reasonable to test a hypothesized family relationship between, say, Phyllozoon and Dickinsonia (which have enough similarities to make such a comparison possible), but that it would be problematic to test phylogenetic similarities between all of the Ediacaran forms.
Not so, replied Seilacher, for years ago he had hypothesized that Spriggina is merely a variant of Charniodiscus. Runnegar responded that smaller taxa such as Spriggina had a very different type of preservation. Seilacher replied that, on the contrary, he had seen these smaller taxa on a slab with Dickinsonia, sharing exactly the same kind of preservation. Runnegar acknowledged that they are indeed on the same slabs. Seilacher continued by noting that he saw in the Ediacarans a sequence of budding, growth that is bipolar or unipolar, and no legs or any other type of organs, and furthermore no differentiation. Runnegar claimed that the discussion was not going anywhere because of differences in interpretation of the same fossils, to which Seilacher agreed. Runnegar added that in his opinion, Spriggina and especially Tribrachidium were very far removed from Seilacher's concept of the Vendobiont air mattress style of construction. Seilacher replied that in his opinion, these forms could be reconciled with a Vendobiont placement. In Tribrachidium, he sees two orders of element bifurcation, the most distal of which could be a type of quilting. The coarser (earlier) order of bifurcation looks to Seilacher to be very much like the stem sections of Charnia or Charniodiscus in Newfoundland. He noted that this may indicate a different kind of material in these parts of the bodies of Tribrachidium, Charnia, and Charniodiscus, perhaps indicating the presence of a more solid or gel-like consistency, in contrast to the more biologically active, foliate parts of these organisms. I asked Seilacher whether he was suggesting that Tribrachidium represented a fossil holdfast. No, he viewed it as a complete organism with three strengthening radii forming the basis for quilted, foliate parts of the creature. Gehling added that he was finding that the Ediacarans had another level of structure, overprinted on the primary structure that Seilacher had just described, including "strange fanlike structures radiating out over" the branches and subdivisions of the branches themselves. Sometimes these finer features were not preserved at all.
Seilacher acknowledged that there were disagreements, then proposed that we provisionally call the organisms Vendobionta whether or not we all accepted the phylogenetic implications of the term. Runnegar added that he was willing to use the term Vendobionta without provision but would use it only for four of the genera. Runnegar objected to Seilacher's shoehorning of most of the other Ediacaran taxa into the Vendobionta. Seilacher agreed to disagree.
On August 5 we drove to the casting site.32 Silicon had not yet set because of a frost the night before. I took Dolf and Edith up to the two archaeological sites. Then I drove with Erni to the Pflug locality between the casting site and yesterday's first site, the type locality of Ernietta.
Once again, the fossil horizon is at the top of the quartzites just before they give way to buff carbonates. We saw Fladle structures33 similar to those seen just before the first fossil find of Pteridinium. I caught, mesmerized, and released an Agama lizard (family Agamidae).34 Back at the casting site we found clusters of Protolyellia. Jim Gehling found a Paramedusium africanum Gurich 1930 (figure 4.5) in fine clastics just downsection from the main Pteridinium bed. This, according to Jim, was a happy find because the type specimen of Paramedusium africanum was lost during World War II.35 I found a strange specimen that we dubbed the wrinkled frond.
According to measurements by Jim Gehling and Frieder Pfluger, the axes of the Pteridiniums trend north-south; paleocurrent indicators are to the southwest.
Later in the day Seilacher entertained us with stories of his past exploits. Off the coast of Sudan, in a scene reminiscent of Captain Nemo's dive in Twenty Thousand Leagues Beneath the Sea, Seilacher cut himself on the edge of a giant Tridacna clam. Another time, astonished tourists in a glass-bottomed boat peered through the glass to see Seilacher busily at work, diving on the seafloor.
The night of August 5 was very cold in the hotel; no heat. We felt the bite of one-star accommodations. Before retiring we had a lot of red wine, conversation, and Jim Gehling's splendid photographs of fossils from Australia.
The morning of August 6 we planned to drive to Luderitz on the coast. Peter and Hans checked the tire pressure in the Volkswagen minibus at the Aus Namib Garage (Souvenir, Koeldrank, Sigarette). A Trans Namib oil truck pulled up beside us. A poor black child with holes in shoes looked on. He looked cold. I gave him some cash.
It is 125 km from Aus to Luderitz. We passed rounded granitic outcrops west of Aus. My attention was captured by a spheroidally weathered granite dome monolith. Edith Seilacher commented that it must be a large ostrich egg. The terrane of this area is not unlike the rounded granites of Joshua Tree National Monument in California; another boulder-hopper's paradise. We spotted two ostriches on the side of the road, under the "egg."
Next dark conical hills appeared, protruding from a tan plain dotted with trees. Bush turkeys glided to the left, seeking cover in the hexen-hazel (witch hazel). A dark trapezoidal massif rose to the right.
A cautionary sign was posted beside the road:
Warning. You are now entering the sperrgebit [sic] diamond area
No. 1. You must not move to left or right of road without permit by order of the Diamond Resources protection statute.
Are the dark hills kimberlites, I wondered? A jackal to the left of the road looked a great deal like a North American coyote. The hills to the left of the diamond area are marbled with browns and pinkish tans of the Namaqua Metamorphic Complex. Sign on right:
Namib Feral Horse
The Schutztruppe's horses were released after they were captured, and went feral just like the mustangs and feral burros of the American West.36
The dark trapezoidal mass continued to loom off to the right. The Gorub station appeared at the left. It is the first station after Aus. Railroad construction engineers had a habit of putting stations at regular intervals, every 15-20 km, to service steam engines.
A single springbok was seen to the left. The vegetation all but vanished as we crossed a sandy, pebbly plain. There were some tire tracks and stubble beside the road, but that was all. Telephone lines ran parallel to the railroad tracks on the left. Power lines intersected and marched southwest through a wind gap that looks like Dr. Seuss's West Jehosephat in Oh the Places You'll GoP1
Lüderitz was now 80 km distant and grass had returned to the plain. Sand dune crests were visible to the right of the road; they merged smoothly into the pediments that support the distant mountain ranges. We stopped for a photo. Frau Seilacher pointed a Blaupunkt video camera. Peter, who had been driving, aimed his Pentax. Being low on film, I retired from the vehicle simply to relieve my bladder. My friends cried out: "Diamond area—Not allowed! Not allowed!"
Tasteless humor seems endemic to geological field work. Herr Seilacher told of a trip to Jordan; as a participant turned away from camp to pray to Mecca, an American followed him, unwittingly, to urinate. Dolf had to stop the American.
Seilacher continued: A well-known Swiss professor was much admired by students, who followed him around, making remarks to try to impress him. Finally, they followed him into a crevice in a canyon that got narrower and narrower, until he finally exclaimed, "You don't have to follow me for this!"
An orange and green Leyland truck passed us on the right, going in the opposite direction. The Tsaukuib Station appeared on the left, the name derived from the Bushman language. A blue and white bus pulled off of the road ahead; as we passed we saw that it was a Safaris Limited bus filled with South African tourists. More possible kimber-lites to the right—black hills with low relief—surrounded by a black and tan alluvial fan. One hill, apparently not a caldera, nevertheless looks like a Namibian Diamond Head.
The dunes were more visible now and had an orange color with a band of blue ocean beyond. The vegetation became sparse again. The kimberlites in this area are not the appropriate age for diamonds; most diamonds are transported down the Orange River mouth. The diamonds are carried by currents along the coast. There are lesser quantities of them to the north of the mouth, but the highest-quality diamonds are found in the Namibian north coast because of a natural sorting process.
A game ranger who had caught a baby ostrich and carried it to the hotel in Aus in a cardboard box a few days ago (it was quite cute next to the fireplace) remarked to us that ostriches have been killed by hunters seeking diamonds in their gizzards. The diamond gastroliths, being of course harder than all other rocks, preferentially survive the gizzard grinding phase of the digestive process. Some very large and valuable diamonds have been collected at the expense of ostriches' lives.
Written in white rock on hills to the left is the cryptic message
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