Seven Skeletons
Page 20
Portrait of Kadanuumuu, Australopithecus afarensis, published in 2010. (Yohannes Haile-Selassie and Cleveland Museum of Natural History. Used with permission)
Even at his press release, the official description of Kadanuumuu relied heavily on the audience’s familiarity with Lucy. “The new skeleton comes from the Rift Valley in the central Afar of Ethiopia, about 330 kilometres northeast of Addis Ababa,” Dalton noted. “Found in 2005 … a long day’s walk north of Hadar where Lucy was discovered … the skeleton is estimated to be nearly 2 metres tall. Lucy was just over 1 metre tall.”5 A short 2010 piece in National Geographic titled “‘Lucy’ Kin Pushes Back Evolution of Upright Walking” supplies similar information about Kadanuumuu’s morphology and skeleton, but once again defines the fossil against Lucy. A 2015 study that examined the question of sexual dimorphism—the physical differences between males and females of the same Australopithecus afarensis species—again juxtaposed Kadanuumuu with Lucy. This would be expected given how significant Lucy is—but what really undercut Kadanuumuu was the study’s emphasis on Lucy. Her name was first in the study’s title, weighting the better-known fossil over the newer, less-studied one.6 The Kadanuumuu fossils expanded the details of how we think about a fossil species—especially how we think about interspecies variation and the nuances of locomotion for Australopithecus afarensis hominins. But for all the emphasis on the fossil’s bipedality, culturally speaking, Kadanuumuu has trouble standing on his own two feet.
Why? Because Kadanuumuu is a semicomplete Australopithecus afarensis whose origin story is fairly de rigueur for paleoanthropology. There isn’t anything about the fossil, its discovery, its science, or its museum life that really jumps out and grabs audiences—nothing that revises the hominin phylogenetic tree or that inspires an entirely new canon of scientific inquiry. Kadanuumuu does not represent a new species or a new archetype. He doesn’t represent a new set of questions to paleoanthropology and he doesn’t highlight really new methodologies.
Kadanuumuu is a fossil—much like Turkana Boy or Mrs. Ples—that, perhaps, will jingle some note of recognition in audiences, but will quickly fade. (Mrs. Ples is the adult Australopithecus africanus discovered in Sterkfontein, near Taung, by Robert Broom in 1947 that substantiated the Taung Child. Turkana Boy is a Homo ergaster specimen found by Richard Leakey near Lake Turkana in Kenya. Both are important discoveries in the history of paleoanthropology, but simply haven’t risen to the celebrity strata of other fossils.) Kadanuumuu, like Mrs. Ples, props up other fossils. On the off chance that Lucy’s luminous essence might diminish, Kadanuumuu is right there, ready to lend the little cachet that it has to offer; Kadanuumuu exists as a secondary character to Lucy—a member of the Australopithecus afarensis supporting cast, her understudy. It’s as if Kadanuumuu is a bit player that you sort of recognize on TV, but it takes three clicks on Wikipedia to remind yourself why you recognize the actor. It’s difficult to become a celebrity fossil living in Lucy’s shadow. It’s important to note that not all researchers necessarily want fossils to become famous; decent, respectable, significant science can and certainly does come from fossils that never quite crack into popular imagination by either chance or choice.
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Sediba is a fossil of a different sort, and the story of his social celebrity is completely different from Kadanuumuu’s. First off, one of the huge differences between Sediba and Kadanuumuu is in the fossils’ names—both culturally and scientifically. Australopithecus sediba bucks the trend of famous fossils colloquially known through popular nicknames. While most famous discoveries rely heavily on the cultural staying power of a nickname—Lucy, the Taung Child, the hobbit—having a strong nickname is by no means a necessary step to celebrity. (Other fossils—Piltdown Man, Peking Man—are certainly simply informal shorthands for the fossil. Davidson Black even suggested calling the first hominin from Zhoukoudian “Nelly” to combat what he saw as explicit sexism by referring to particular hominin discoveries as “man.”) This isn’t for lack of trying for a cute name, though, as a nickname helps a fossil better connect to its public.
A press release issued by the University of the Witwatersrand in 2010, just after the formal publication of the discovery, raised the issue of a nickname and suggested that the fossil ought to have one. “The site continues to be explored and without a doubt there are more groundbreaking discoveries to come forth,” the article reads. “In celebration of this find, the children of South Africa have been invited to develop a common name for the juvenile skeleton.”7 The skeleton, which is type specimen MH1, was eventually named “Karabo” (“The Answer”) by Omphemetse Keepile, a seventeen-year-old student from Johannesburg. In The Skull in the Rock: How a Scientist, a Boy, and Google Earth Opened a New Window on Human Origins—a National Geographic children’s book by Lee Berger and Marc Aronson—the Sediba skeleton is named Karabo, but that name is never used as a persona or shorthand for the fossil, indicative, perhaps, of how the nickname doesn’t seem to have struck a chord. The fossils are known colloquially as Sediba instead.
Sediba is, of course, a shortened form of the fossils’ taxonomic assignment Australopithecus sediba. The specimens are also referred to by their catalog numbers—MH1 and MH2—or, collectively, as the Malapa hominins. In keeping with paleoanthropology’s emerging twenty-first-century tradition of tying fossil names to local languages, the word sediba comes from South Africa’s Sotho language. “Sediba, which means natural spring, fountain or wellspring in Sotho, one of the 11 official languages of South Africa, was deemed an appropriate name for a species that might be the point from which the genus Homo arises,” remarked Berger. “I believe that this is a good candidate for being the transitional species between the southern African ape-man Australopithecus africanus (like the Taung Child and Mrs. Ples) and either Homo habilis or even a direct ancestor of Homo erectus (like Turkana Boy, Java man or Peking man).”8 Tying its name to its region of discovery, Sediba triangulates the geography, taxonomy, and evolutionary narrative that are implied through its scientific name, Australopithecus sediba.
The fossils were undeniably something new for paleoanthropology, but their discovery was, perhaps, not completely unexpected given their geological provenience. The Malapa cave site is part of an area of northern South Africa called the Cradle of Humankind, designated a UNESCO World Heritage site in December 1999. The Cradle is part of a large geologic complex of limestone caves, approximately 7,000 hectares or about 180 square miles in size. For close to one hundred years, the Cradle has continually yielded new fossils and new species that pique paleoanthropology’s curiosity and offer unique possibilities for teasing apart and putting together an evolutionary narrative.
“Hominins are represented in the South African cave sites by over 1,000 catalogued specimens from more than 11 different cave deposits… . At least four and possibly more species of early hominin are found in the South African cave sites,” Lee Berger offers in his Working and Guiding in the Cradle of Humankind. Again, since the geological contexts between East and South Africa are so different, they offer different patterns for fossil discovery and offer evidence for different time periods and geographic places in humanity’s evolutionary story. “While the hominin fossils from South Africa are not nearly as old as the oldest hominin sites in East Africa (East African fossil hominins [like Lucy] may date back over six million years while those in South Africa are probably all less than three million years in age), the South African examples are important because they are almost always more complete and are found in the presence of a much greater range of vertebrates. They are therefore able to tell us a lot about the period in which they lived.”9
One thing that sets the Malapa specimens apart from other fossils was the quick turnaround time between discovery and publication. While Kadanuumuu’s publication was a very respectable five years after its discovery, Australopithecus sediba was published just two years after the discovery of the fossils. The initial 2010 Science publication, titled “Austral
opithecus sediba: A New Species of Homo-like Australopith from South Africa,” was simply a warm-up exercise for the marathon of articles that Berger and his team would publish in the next half decade. In 2011 alone the Sediba team published five in-depth articles about the fossil in a special issue of Science, each article tackling a different anatomical element (pelvis, ankle joint, etc.) and one on the process to assign a geological date to the fossil.
People were charmed by the species—even its detractors and naysayers. As a fossil species, Sediba represents an interesting suite of anatomical characteristics. It has long arms, short powerful hands, a very advanced pelvis, and long legs. This mix of anatomical characteristics made it capable of striding, possibly even running, like a human. It is also likely that Sediba could have climbed. “It is estimated that they were both about 1.27 metres, although the child would certainly have grown taller. The female probably weighed about 33 kilograms and the child about 27 kilograms at the time of his death,” added Berger. “The brain size of the juvenile was between 420 and 450 cubic centimetres, which is small (when compared to the human brain of about 1,200 to 1,600 cubic centimetres) but the shape of the brain seems to be more advanced than that of australopithecines.”10
“These fossils and many others are landmark discoveries in paleoanthropology, finds that have filled crucial gaps in scientists’ understanding of human origins. They are all vitally important. And yet the A. sediba fossils manage to stand out from even this elite crowd, because of the sheer volume and quality of information they contain,” argued science writer Kate Wong in Scientific American. “The finds from Malapa tick pretty much all the boxes on a paleoanthropologist’s wish list. Specimens that preserve multiple skeletal elements? Check. Remains of multiple, coeval individuals (important for understanding variation within a species)? Check. Fossils in near-pristine condition, thus eliminating uncertainties about how pieces fit together? Geological context that allows for precision dating of the fossils? Associated plant and animals remains? Check, check, check.”11
Wong’s informal checklist offers several key points to begin to understand why Sediba has been culturally fast-tracked along its way to famous fossil status. However, simply marking off anatomic features and a successful archaeological context cannot, by themselves, generate a famous fossil. A famous fossil is more than simply the sum of its skeletal elements and more than the significance of its context; a successful celebrity fossil manages to gain traction outside of scientific circles and maintain a cultural persona. Lucy was the first mostly complete skeleton to enter the paleoanthropological record, but it was how her skeleton was used, viewed, studied, and written about that helped push her into a cultural context and give her a public persona. Sediba benefits from being the right fossil in the right time with the right discovery story and a scientist to champion it. Certain elements of its story have historical allusions to the Taung Child’s discovery, and it benefits from a team savvy enough to leverage that history.
In many ways, the open, public access that is associated with the Malapa assemblage makes Sediba a very accessible fossil—both inside the scientific community and outside it. It’s easy to talk about the Malapa specimens because it’s easy to access them through publications, images, scans, and casts. “Many reviews of palaeontological research end with the statement that it would be highly desirable to recover more fossils. In this case, however, the Malapa team has already done that,” argues paleoanthropologist Fred Spoor. “The interpretation of their findings may be a matter of debate, but they have undoubtedly added a spectacular and thought-provoking sample to the hominin fossil record. This achievement represents a major contribution to the study of human evolution in all its complexity.”12
The question of fossil access is raised over and over in paleoanthropology. “The fossils are owned by the people of South Africa, and curated by the University of the Witwatersrand, Johannesburg,” the original Sediba press release read. “They will be on public display at Maropeng in the Cradle of Humankind until the 18th of April 2010, will move to Cape Town for the launch of Palaeo-Sciences Week from the 19th of April and will again be on public display at the Wits Origins Centre during May, on dates to be announced shortly.”13 Not only were the fossils on display immediately following their publication, but casts of the fossils have been working their way through museum, popular, and scientific circles.
Berger’s commitment to transparency and access goes beyond simply displaying the fossils or casts. When the Malapa fossils were being excavated from their breccia, Berger was quick to point out that he wanted to make the entire excavation available online and have nonexperts be able to interact with the scientists. In a 2012 interview with National Geographic, Berger’s enthusiasm for the social life of the fossils was practically contagious: “The world is going to be able to watch and interact live as we expose this discovery. There’s also the possibility that we have two bodies that are intertwined [in the rock]. Part of the fun of this project is that as soon as we find out, the world will find out with us.”14
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Ever since the fossil was published, it’s been very approachable, thanks to the outreach efforts of Berger and his team. Images of Sediba have flooded the Internet, and the fossil shows up everywhere, from scientific publications to museum exhibits to Wikipedia pages—the photographs, formal headshots, and snapped candid field shots help to tell a very visual story of Sediba, particularly the photo of the Malapa discovery itself, which is a candid shot of young Matthew Berger showing off the fossil while it’s still in its breccia matrix. The photo has popped up everywhere from the Malapa site’s Wikipedia page to articles in Nature to museum exhibits in Cape Town’s Iziko Museum.
Matthew Berger and the Sediba fossil, still in matrix, at the Malapa Nature Reserve. (Lee Berger; CC-BY-SA-3.0)
Sediba’s images, through photographs, casts, or reconstructions, are incorporated into a variety of public settings. Since the Malapa specimens are inexorably tied to the Cradle of Humankind, they feature prominently in the Cradle’s visitors’ centers.
As a UNESCO World Heritage site, the Cradle is heavily marketed in South Africa as a paleotourist destination. Its main visitor center is Maropeng, opened December 7, 2005, by then president Thabo Mbeki. Anthropologically, Maropeng offers visitors an opportunity to explore the region’s fossils and human evolution as a whole. Architecturally, the building is covered in grass, rising like a gigantic gnome house out of the stark South African landscape. For the paleoadventurous, the Maropeng center offers a boat trip through the “Tunnel of Time,” where visitors comfortably float from the Cretaceous to the Pleistocene, passing through landscapes full of recorded pterodactyl screams and eventually tooling around Pleistocene volcanoes and ice floes; the Disney-esque boat ride ends at the Hall of Human Origins, which showcases hominins from around the world. All of the “rock star” fossils, from Lucy to Taung to Neanderthals to the Malapa fossils, are featured. At Maropeng and other Cradle museums, Sediba manages to move from a strictly scientific object to tourist ephemera—small 3-D-printed Sediba skulls are sold in gift stores as necklaces and key rings. It’s easy to know about Sediba because Sediba is right there, ready to be known through casts, photos, tourist trinkets, and museum exhibits.
Even in more formal scientific settings, the images of Sediba have dominated over those of other fossils. Take the cover of Science. With its full-page picture and specialized typography, the journal’s cover conveys intellectual gravitas and scientific legitimacy, and has for decades. Ever since Science introduced a picture as part of its cover in 1959, the publication has featured a plethora of images, from thin-section slides and meteorological phenomena to pollen spores and technical instruments. Sediba has graced the cover of Science three times since 2010, a feat unmatched by any scientific discovery in such a short amount of time—and unmatched, in fact, by any other fossil in the history of the journal’s publication.
Only nine covers in over fifty years have featured homi
nin fossils. The first cover was fairly recent: a June 1998 cover showcased a color illustration of the two-and three-dimensional computer imaging of the endocranial capacity of Stw 505, an adult Australopithecus africanus. An August 1999 cover showed the forelimb bones and jaw of a partial skeleton (Equatorius), a very old specimen from a site at Kipsaraman, Kenya. The March 2, 2001, cover gave faces to the 1.7-million-year-old male and female hominins from Dmanisi, Georgia. The rather recently discovered fossil Ardipithecus ramidus, nicknamed Ardi, graced the cover twice in rather quick succession, in October and December 2009.
Unprecedented in Science’s history, Australopithecus sediba was on the cover, on April 9, 2010, September 9, 2011, and April 12, 2013, each cover showing Sediba in different poses: one with the skull, one with Sediba’s hand, and the final one a fully reconstructed skeleton with the left hand slightly extended, almost inviting the reader to join him. (The most recent paleo-related cover to date, October 18, 2013, was a photo of a 1.77-million-year-old complete adult skull from Dmanisi, designated as early Homo.) Each of these covers conveys the importance of the fossil discovery. Framed enlargements of Sediba’s Science covers hang in the hall of the Evolutionary Studies Institute at the University of the Witwatersrand—like an agency proudly showcasing headshots of its successful models.