Vox writer Joseph Stromberg visited the Forensic Anthropology Center at Texas State University, and has written an in-depth description of his visit: "The science of human decay: Inside the world's largest body farm". The article features the work of Daniel Wescott at Texas State, and provides a great account of how the science of human decomposition developed.
The article gives some historical perspective, describing how Bill Bass got started studying decomposition at Tennessee, and goes into some detail about how today's research differs from that history. Among other things, forensic anthropologists have developed a much stronger understanding of the microbes that are involved in decomposition:
For Wescott and the other researchers, caged decomposition presents the most interesting scientific experiment at the body farm. It was once thought that the bacteria that drive decay are simply the same species inside you while you're alive, but it's since been discovered that a succession of different species carries it out over time. Some of them are indeed present during life, but others are brought to the body by flies and beetles. Meanwhile, some bacteria species release chemicals that actually attract particular kinds of insects — and proteins in those insects' saliva kill off competing bacteria. Further, these insects are prey for mice, which in turn attract rattlesnakes and other larger predators. A decomposing human body, it turns out, creates a remarkably complex, tightly evolved, and underappreciated ecosystem. Scientists are now calling it the necrobiome.
This seems to be decomp week in the media, which is probably due to Halloween coming up this Friday. But this article is really superb. I will be distributing it to my introductory anthropology students when we approach our forensic anthropology inquiry at the end of the semester.
One important thing to note is that all the research is done upon bodies that are donated for this purpose. Body donation has become incredibly important to anthropological work of all kinds. The article has a sidebar that discusses the reasons why people donate their bodies for science, and why the study of decomposition can be a really important avenue for body donation.
One thing that the article doesn't discuss is the scientific value of the bones, after the body's use in decomposition research has ended. Some decomposition research does involve damage to the bones (the article discusses the effects of vultures; some decomposition research also investigates the effects of cremation). But the overwhelming majority of bones become available for accession into study collections at these forensic anthropology research centers.
The skeletal material from the University of Tennessee forensic research unit constitutes the single most important collection for understanding variation within the skeletons of living Americans. Most collections of human skeletal material in museums and universities were acquired early in the twentieth century, or represent archaeological remains. Those are important collections, but do not represent today's biology -- people today are much heavier, live longer, suffer fewer ill health episodes early in their lives, and often survive surgeries and skeletal implants when they reach advanced ages. To understand how human biology affects bone today, and to understand the variation in bones of living people, new collections are incredibly important. They are literally priceless, because collections of this kind cannot be bought. They result only from the generosity and interest of donors who leave their remains for this purpose.
John Ioannidis is well known as a critic of the way science has usually been practiced. I've linked to his work before ("Link: John Ioannidis and the scientific workforce core", "Conference criticisms"), although I haven't written directly about his most famous work on the reasons why most scientific findings go unreplicated.
Ioannidis has a recent article in PLoS Medicine that discusses ways to change the scientific research enterprise. He focuses on two criticisms of the present scientific research practice: Most published articles are based on samples that lack sufficient power to justify the claimed associations or effects, and a large majority of resources (he cites 85% as an estimate) are "wasted". Based on these considerations, he writes about several ways that scientific research could be changed to increase the pace of genuine discovery and reduce the rate of spurious results.
The current system values publications, grants, academic titles, and previously accumulated power. Researchers at higher ranks have more papers and more grants. However, scholars at the very top of the ladder (e.g., university presidents) have modest, mediocre, or weak publication and citation records . This might be because their lobbying dexterity compensates for their lack of such credentials, and their success comes at the expense of other worthier candidates who would bring more intellectual rigor and value to senior decision making; equally, it could be because they excel at the bureaucratic work necessary to keep the mind-boggling academic machine going, and their skills enable more scientifically gifted colleagues to concentrate on research. The current system does not reward replication—it often even penalizes people who want to rigorously replicate previous work, and it pushes investigators to claim that their work is highly novel and significant . Sharing (data, protocols, analysis codes, etc.) is not incentivized or requested, with some notable exceptions –. With lack of supportive resources and with competition (“competitors will steal my data, my ideas, and eventually my funding”), sharing becomes even disincentivized. Other aspects of scientific citizenship, such as high-quality peer review, are not valued. Peer review can be a beneficial process, acting as a safety net and a mechanism for augmenting quality. It can also be superficial, lead to only modest improvements of the reviewed work, and allow for the acceptance of blatantly wrong papers ,. That it is so little valued and rewarded is not calculated to encourage its benefits and minimize its harms.
I don't endorse all of his arguments, which are heavily skewed toward the biomedical research fields. These areas are after all his specialty, and more "pure science" areas of research such as paleontology and astronomy are not his aim. On the other hand, physics and genetics share a great deal in the way they approach new scientific research projects today: Both fields have come to rely more strongly upon large-scale collaborations, both have begun to institute more quality assurance in their software and tool development, and both have adopted more open access protocols toward data collection. Both also have recognized that very stringent standards on statistical significance are necessary to reduce the reporting of results that will almost certainly fail to be replicated in larger-scale studies.
Paleoanthropology has begun to embrace a scientific approach with wider-scale collaboration and data sharing. I think we are fortunate in being a relatively small field in which the contributions of peer reviewers and editors are much more recognized than in many fields. I think this recognition would be even greater if the reviews were less anonymous, and I have encountered an increasing number of reviewers who have refused anonymity (often including myself). But even more important than peer review is a greater discussion and conversation about research directions and priorities. If we can get students and professionals collaborating with each other on larger-scale research datasets instead of working alone in isolation, we'll increase the replicability of results and improve the significance of everyone's work.
Ioannidis JPA (2014) How to Make More Published Research True. PLoS Med 11(10): e1001747. doi:10.1371/journal.pmed.1001747
Notable paper: Kopp GH, Roos C, Butynski TM, Wildman DE, Alagaili AN, Groeneveld LF, Zinner D. (2014). Out of Africa, but how and when? The case of hamadryas baboons (Papio hamadryas). Journal of Human Evolution (in press) doi:10.1016/j.jhevol.2014.08.003
Synopsis: Humans are not the only primate to have dispersed from Africa during the Pleistocene. Savanna baboons, widespread across eastern Africa, established a population on the Arabian peninsula during the last 150,000 years. Gisela Kopp and colleagues show that the diversity of baboons increases from north to south along the Red Sea coast in Arabia, and suggest that the baboons may have crossed the Strait of Bab-el-Mandab during the low water period of the Late Pleistocene, more than 70,000 years ago.
Important because: Archaeologists and geneticists have recurrently suggested that humans may have made a Bab-el-Mandab crossing via a "southern route", instead of coming across land via the Sinai peninsula. The interest in a southern route for humans has most recently been spurred by archaeological similarties between Arabian and African Middle Paleolithic-era assemblages. Those similarities date to the same general time period that baboons were establishing this Arabian population.
But... The genetic data here don't exclude an overland or mixed source for the Arabian baboon population. And of course, the dispersal abilities of baboons are probably not the same as humans, so the baboon analogy may not be relevant to us. Still, along with other African fauna like cheetahs and striped hyenas, the baboons help to show that Arabia was repeatedly colonized by African forms.
The historian of science Lydia Pyne has published a couple of recent articles that detail interesting aspects of the history human evolution. The first is about science's changing perspective on Neandertals, "Our Neanderthal complex", which appears in the most recent issue of Nautilus.
I must say my favorite part is how she traces Boule's concept of stupid and inferior Neandertals up through the years: Instead of describing these ideas as simply outmoded, she recognizes how they contributed to the work of recent anthropologists, with Richard Klein as a visible manifestation.
Even the language of extinction imbued Neanderthals with an aura of evolutionary fatalism: “demise,” “fate,” and “loss” helped us cast our interspecies interaction as a relationship between winners and losers. “It is not difficult to understand why the Neanderthals failed to survive,” noted Richard Klein in the third edition of his seminal textbook, The Human Career, in 2009. “The archaeological record shows that in virtually every detectable aspect—artifacts, site modification, ability to adapt to extreme environments, subsistence, and so forth—the Neanderthals lagged their modern successors, and their more primitive behavior limited their ability to compete for game and other shared resources.”
Pyne comes at the end to an essential point about Neandertals: We long defined ourselves as whatever the Neandertals are not. Now we have begun to explore the implications of defining them as part of our family.
The Chicago Tribune sent reporter Christopher Borrelli to the Field Museum to see how bodies are reduced to skeletons: "Inside the Field Museum's hidden flesh-eating beetle room".
There are nine beetle cages, each roughly the size of a home aquarium, each topped with mesh lids, each layered with a sedimentary bedrock of exoskeleton, excrement and freshly dead flesh-eating beetles. As Goldman lifted the lid of a cage and sifted around the white ribs and skull of a raven, she considered how many beetles were in this room.
She decided she didn't know — millions? Occupancy rates are unknown.
Now, to shiver your spines: The flesh-eating beetles of the Field Museum are a bit of a mystery. A stray dead chipmunk or two aside, "everything in this museum is documented, even the most mundane objects," Goldman said. "Yet these beetles: It's completely unknown how we got them. When I came here I was curious (about where they came from). This colony is a black hole.
It's a great story for Halloween week, complete with creepy slideshow.
Qiaomei Fu and colleagues from Svante Pääbo's lab have reported on a genome from northern Siberia that dates to 45,000 years ago. The genome comes from a human femur that was eroding out of a bank of the river Irtysh, which is in the Siberian plain near Omsk. The specimen is the shaft of a femur lacking its ends, and has no special similarities to archaic humans such as the Neandertals. It would certainly be unsurprising for a modern human to have this anatomy, and would likely be categorized as a modern human femur even without the genome. But the genome is the earliest ever recovered from a modern human individual, and therefore gives us some very useful information that we could not get in any other way.
Another mystery population?
To me, the most interesting part of the paper is the D-statistic comparison with other ancient and modern genomes. The D-statistic is basically a measure of genome-wide similarity, considering only those alleles derived relative to some outgroup. The results are useful for assessing mixture between ancient populations. For example, people who have ancestry within sub-Saharan Africa have fewer derived alleles in common with Neandertals than people who lack recent sub-Saharan ancestry. The D-statistic in a comparison of a non-African and a sub-Saharan African genome with Neandertals will show a skew toward Neandertal similarity in the non-African genome. That is one way of assessing Neandertal ancestry of living people.
The Ust'-Ishim genome seems to be ancestral to nobody. Consider the result of D-statistic comparisons with living Asians, Native Americans and Europeans, and two ancient genomes from Eurasia -- the Mal'ta and La Braña specimens. Here is the figure showing the D-statistics as compared with other specimens:
In that figure, the value of zero (with a vertical line across comparisons) indicates that the genomes listed on left and right sides of the figure have the same proportion of derived similarities with the index genome (in all cases, the Ust'-Ishim genome). A positive value skews toward the right genome; a negative value toward the left. The top panel shows that Ust'-Ishim is more similar to genomes of non-Africans than it is to sub-Saharan African genomes.
The case of Mal'ta is most interesting as a comparison. This individual from eastern Siberia near Lake Baikal dates to around 24,000 years ago. Its genome was described earlier this year by Raghavan and colleagues (2014), and one of their major conclusions was that the similarity of this genome with Europeans on the one hand, and Native Americans on the other, probably shows a common source population in Siberia that had contributed to the rise of both these living populations. That is not to say that both these populations derive fully from ancient Siberians, but that some ancient Siberians related to Mal'ta later became part of the population that entered the Americans, and that some other ancient Siberians related to Mal'ta would ultimately migrate into Europe.
Ust'-Ishim shows no such pattern. It is not more like the Mal'ta genome than it is like any other genomes of Asians or Native Americans. It is not like any living population of Asians or Native Americans more than any other.
At the same time, Ust'-Ishim is less like living Europeans than it is like any of these Asian populations, and less like living Europeans than it is like the Mesolithic-era La Braña individual, even though that individual lived in Iberia. Fu and colleagues suggest that the recent population of Europe must have gotten some of its ancestry from other populations that were not part of the initial out-of-Africa spread represented by the Ust'-Ishim individual. That could mean later Africans, or it could mean one or more West Asian populations that contributed neither to the later dispersal of humans into the rest of Eurasia and the New World nor to the Mesolithic occupation of Europe by modern humans. I wrote "Mesolithic" there very consciously, because it seems plausible until demonstrated otherwise that earlier Upper Paleolithic Europeans might represent yet some other population.
Considering the fact that Ust'-Ishim is equally similar to all Asian and Native American populations and equally similar to the two ancient genomes, Fu and colleagues write this:
This suggests that the population to which the Ust’- Ishim individual belonged diverged from the ancestors of present-day West Eurasian and East Eurasian populations before—or simultaneously with—their divergence from each other.
I would give a strong interpretation to this. It seems unlikely that Chinese (Han) and Andaman Island (Onge) populations could be uniquely descended from this ancient Siberian individual, so Ust'-Ishim is not at the stem of the later diversification of Eurasian people. That means that these later people derive from a different group than that represented by Ust'-Ishim. The initial dispersal of humans into Eurasia contained at least one dead-end population that contributed at most some very small amount of ancestry to living people.
This is not an isolated case, it is another example of what we see throughout the world: Ancient people represented by DNA that seem to have very little to do with the people who live in the same areas today. We're not finding the ancestors of living populations so much as we are finding branches of populations we did not know existed.
I've written about the human mutation rate many times here, and in print (Hawks 2012). The new paper is interesting because it is the first modern human we have at high coverage, where the age is sufficient to estimate the number of missing mutations that would be expected in a descendant living today. Even though Ust'-Ishim may have no living descendants, this is a measure of how short his DNA branches are compared to the branches connecting living humans to their common ancestors.
Given that, the authors find that the mutation rate would need to be fairly low, on the order of 1 times 10-8 mutations per site per generation, to account for the Ust'-Ishim data. That low rate is more or less the same as estimated from looking at parents and offspring living today, which is a good piece of evidence that the per-generation rate we measure in living people is not different from the per-generation rate averaged over longer periods of time. As the authors point out, this means that a lot of ancient events estimated from DNA only must have happened longer ago than was claimed prior to a couple of years ago.
Several notable aspects of this genome can tell us more about Neandertal ancestry than we knew before.
The genome has no greater Neandertal ancestry than in living non-Africans. At least in this part of Asia, there was no greater opportunity to interbreed with Neandertals than elsewhere for ancient people.
Shared alleles with Neandertals are co-inherited across longer distances in the Ust'-Ishim genome than in living people. That is, there is greater linkage disequilibrium between Neandertal-derived alleles in the Ust'-Ishim genome. That indicates that Ust'-Ishim lived much sooner after its Neandertal ancestors than we do.
The pattern of linkage disequilibrium indicated by the Neandertal segments of his genome allows us to estimate the time that the Ust'-Ishim individual had Neandertal ancestors. This time seems to have been between 50,000 and 60,000 years ago.
Here's an excerpt from the section of the paper where they describe the identification of Neandertal-derived segments:
To test if this is indeed the case, we identified putative Neanderthal DNA segments in the Ust’-Ishim and present- day genomes based on derived alleles shared with the Neanderthal ge- nome at positions where Africans are fixed for ancestral alleles. Figure 5 shows that fragments of putative Neanderthal origin in the Ust’-Ishim individual are substantially longer than those in present-day humans. We use the covariance in such derived alleles of putative Neanderthal origin across the Ust’-Ishim genome to infer that mean fragment sizes in the Ust’-Ishim genome are in the order of 1.8–4.2 times longer than in present-day genomes and that the Neanderthal gene flow occurred 232–430 generations before the Ust’-Ishim individual lived (Supplementary Information section 18; Fig. 6). Under the simplifying assumption that the gene flow occurred as a single event, and assuming a generation time of 29 years, we estimate that the admixture between the ancestors of the Ust’-Ishim individual and Neanderthals occurred approximately 50,000 to 60,000 years BP, which is close to the time of the major expansion of modern humans out of Africa and the Middle East. How- ever, we also note that the presence of some longer fragments (Fig. 5) may indicate that additional admixture occurred even later. Nevertheless, these results suggest that the bulk of the Neanderthal contribution to present-day people outside Africa does not go back to mixture between Neanderthals and the anatomically modern humans who lived in the Middle East at earlier times; for example, the modern humans whose remains have been found at Skhul and Qafzeh
As usual, we should be cautious about assumptions. In particular, the assumption that admixture happened at a single time is almost certainly wrong. This amounts to the idea that the last Neandertal ancestors of Ust'-Ishim were his only Neandertal ancestors. As the paper suggests, there may have been more recent ancestors. I would point out that a small amount of Neandertal ancestry going further back in time would be indistinguishable from this pattern. If we imagine that Neandertal mixture into Eurasian modern human populations may have happened over some range of times, these data show that the modal time was probably in the time range from 50,000 to 60,000 years ago but do not exclude tails going further back in time or closer to the present.
That being said, it is pretty important that this genome adds resolution to the timing of Neandertal ancestry. We are not looking at a situation in which the bulk of mixture happened earlier than 100,000 years ago. We're looking at mixture that happened not too long before humans reached China, Australia, and obviously Arctic Siberia.
In contrast to its Neandertal DNA heritage, the Ust'-Ishim genome has no evidence of ancestry from the Denisovan population. That may or may not be surprising -- the genome may be from the same time zone but that doesn't make it especially close to Denisova; we don't know when the Denisovans lived there or where other modern humans may have mixed with them. But it is at least unfortunate, as it deprives us of the opportunity to examine the date of Denisovan ancestry with the same method as Fu and colleagues used for Neandertal ancestry.
Fu, Q. and many others. (2014). Genome sequence of a 45,000-year-old modern human from western Siberia. Nature, 514, 445-450. doi:10.1038/nature13810
Hawks, J. (2012). Longer time scale for human evolution. Proceedings of the National Academy of Sciences, 109(39), 15531-15532. doi:10.1073/pnas.1212718109
Raghavan, M., Skoglund, P., Graf, K. E., Metspalu, M., Albrechtsen, A., Moltke, I., ... & Willerslev, E. (2014). Upper Palaeolithic Siberian genome reveals dual ancestry of Native Americans. Nature, 505, 87–91. doi:10.1038/nature12736
Notable paper: Aubert M, Brumm A, Ramli M, Sutikna T, Saptomo EW, Hakim B, Morwood MJ, van den Burgh GD, Kinsley L, Dosseto A. (2014). Pleistocene cave art from Sulawesi, Indonesia. Nature 514:223-227. doi:10.1038/nature13422
Synopsis: The paper is mostly devoted to providing date estimates for the formation of speleothems, in this case "cave popcorn" deposits of calcite that have formed on surfaces that bear rock art. The authors show that many examples of rock art are Paleolithic in age, and paintings from at least three sites are more than 35,000 years old -- making these older than Chauvet Cave in France, the oldest example of figurative art in Europe. The oldest date for the Sulawesi rock art is 46,000 years ago, from Leang Barugayya 2.
Important because: The paper provides a second dot on the map of representational art before 30,000 years ago.The rock art from this area of Sulawesi was first noted by prehistorians more than 50 years ago. In southwestern Europe, rock art specialists have worked hard to develop a chronology of cave art based on chronology, but really that effort depends on assumptions about cultural groups that we cannot generally justify -- and rock art far from Europe could never fit into a European chronology. The appearance of new methods of dating the overlying speleothems has helped to open the science.
A clever article by Rose Eveleth for The Atlantic looks into a peculiar regularity in the history of art: "Nobody Knows What Running Looks Like". Eveleth reviews the findings of a recent paper by Julian Meltzer, which investigates representations of human gait throughout the history of art.
Normal human gait has the arms swinging opposite the legs. A step forward with the right leg is accompanied by a swing forward with the left arm. This arm swing facilitates a counter-rotation of the trunk and overall conservation of energy, and is natural for most people as soon as they learn to walk.
Strangely, most artists who depicted humans running or walking have gotten it backward: showing people swinging the same arm and leg forward, not opposites. Eveleth shows some great examples from ancient Egypt up to the present day.
When it comes to art, it’s possible that rather than being an error, the awkward, one sided lurch forward is an artistic choice. In Egyptian art, for example, artists followed strict rules about the position of the head and body. But as art evolved, and as accuracy of form become more and more important, it’s hard to imagine why someone like Da Vinci or Donatello would intentionally draw a person running in such an inaccurate pose. And modern “how to draw” guides are certainly not intentionally teaching someone the wrong posture.
A survey of people shows that they report this aspect of gait significantly worse than chance...
And when participants were asked to pose in mid-run, only 14 percent of them picked the pose that actually reflected running. The other 86 percent froze with the same sided arm and leg moving forward.
The investigation into this common error leads to some interesting conclusions about how we learn to move.
Meltzoff J. (2014). Errors in the making and perception of art images of human gait: Psychological explanations. Psychology of Aesthetics, Creativity, and the Arts 8(3):321-329. doi:10.1037/a0036669
The Mail and Guardian has a nice article about the work of John Gurche, written by Sarah Wild: "The next best thing to a time machine". Gurche is doing a guest lecture at the University of the Witwatersrand this week, and the article reviews his work and the importance of paleoartistic reconstruction to the science of paleontology:
“The world – worlds? – that science reveals is breathtaking, full of wonder. But the language of science is not accessible to many people. To convey that wonder, or even just to create an image that communicates what the scientific literature is saying, you need art,” he says, arguing that this is an example of science serving art. “Science can feel like a muse to the artist.”
But in this case, the muse is a collection of bones, painstakingly excavated from the ground over the course of years. In the coffee room in the Bernard Price Institute at Wits, the researchers have a puzzle on the table to help them to sharpen their visual abilities for piecing together ancient fossils.
When it comes to palaeoscience, these researchers have to put together a puzzle without knowing much of the picture in advance, and Gurche in effect has to colour it in.
I've seen skilled anatomists spend an awful lot of time with those jigsaw puzzles in the tea room.
The collaboration between artists and anatomists is so important to both fields of study. The best artists share with anatomists a skill of vision, developed over thousands of hours of close study, that is impossible to describe with words.
Gurche's recent book, Shaping Humanity: How Science, Art, and Imagination Help Us Understand Our Origins, provides a deep perspective on the creation of his distinct visions of ancient human ancestors.
ScienceOnline has now ended forever. Many people in the next several weeks will doubtless offer their perspective on why the organization failed. They will point to a series of poor decisions, a tone-deaf response to a sexual harassment scandal, and an organization's alienation of thoughtful community members.
I'd like to consider for a moment why it succeeded so brilliantly for more than five years. ScienceOnline represented a new wave of fusion between scientists and culture. That spirit has been taken outward into many directions by many of the participants, including me. The conferences provided a nexus for people from all walks of science to experience a changing landscape of sharing and doing science.
Here's a list of six things that I think helped to make ScienceOnline work.
Youth. The fascination of science is not obvious to everyone, and science has always relied on talented interlocutors to translate important results into popular culture. From the 1990s to the mid-2000s, many of the most widely influential science communicators -- journalists and high-ranking scientists -- were old, crusty, and hidebound. Online culture was new, young and full of revolutionary and romantic ideas. In science, where the most senior ranks are very white and very male, youth also brings diversity. The participants in ScienceOnline were well placed to write and speak about science in new ways, which was exciting to people.
Community. ScienceOnline created a forum in which online friends could meet. More important, the conference enabled people to meet who didn't know each other's online work. Many participants didn't even have online work, in the sense of a blog or other regular writing presence. The conference was built around their mutual interests in new forms of doing, publishing and communicating science. They already formed an informal network of people across institutions, disciplines, and professional callings -- from students to writers to full-time scientists. ScienceOnline helped to solidify this network and enable its members to call upon each other's skills outside of the usual professional silos.
Maker culture. People who engage with science and the internet are creators. They make things, grapple with new technology, hack the source. ScienceOnline gave these people a place to share what they were making. Artwork, ebooks, video, websites, software -- even new startups like Mendeley -- were all shared at ScienceOnline. The conference was full of "how-to" sessions, focusing on the practical side of making things. Some were beginner sessions that helped people learn how to blog, how to manage intellectual property, how to be a better writer. One year, I even organized a nuts-and-bolts workshop on how to migrate to a new server. Where else could one go from a session on documentary film techniques to a session on e-book platforms, and have both of them hit the right level? It is just fun to be around so many different people who are making different kinds of things.
Populism. Science is hierarchical. Senior scientists get the most resources and are allocated the most attention at conferences. At ScienceOnline, students, upcoming writers and journalists, and more established scientists and other academics all collaborated to present the program, all attended the same events and sessions, and most importantly all interacted on an equal footing. The conference encouraged sessions in which the attendees were active participants, not a passive audience. Much has been written about the deficiencies of the "unconference" format, in particular how relying on the crowd of attendees can miss valuable expert knowledge. But giving a broader sample of attendees a voice enabled them to help create knowledge instead of passively receiving it.
The Waiting List. Let's face it, nothing is cooler than the nightclub with a line out the door. At its peak, the tickets for the ScienceOnline conferences were snapped up within minutes of registration opening. In those years, more than a hundred potential attendees might get on a list to wait for cancellations. The organization did something very smart with this popularity: It gave away spaces to people who were willing to propose and organize great sessions. That idea fueled a diverse program with highly motivated presenters and facilitators. These people helped to minimize the inherent disadvantages of the "unconference" format, preparing and focusing material that would be engaging to the participants. As the organization started to falter, it neglected the value of session organizers increasingly discarded this strength, devaluing the contributions of session organizers.
The Backchannel. ScienceOnline was not the first conference with an active Twitter backchannel, nor was it the first to have livestreaming of sessions. But it was the conference that made offchannel more important than onchannel. What other conference had bandwidth demands on the scale of the Superbowl? The video streams enabled people offsite to participate virtually in the meeting through Twitter, reacting to sessions with their blogs, and thinking about how to organize similar sessions at other meetings.
Many of the great things about ScienceOnline have spread across the culture of scientific meetings. Those of us who tweet from scientific meetings have developed a backchannel bond, almost a shadow conference going on behind the scenes. Other meetings may not be egalitarian unconferences, but at least the senior scientists don't seem to grandstand during the question period quite so much as they used to. Some of today's best-known and most talented science journalists are people who met and learned from each other at ScienceOnline. Those relationships continue to shape the landscape of science communication.
Many of these changes may have been more or less inevitable, as a wave of technology enabled new forms of interaction among younger scientists and journalists. ScienceOnline rode this technology wave, capitalizing on the interests of people adopting new modes of writing and interacting. But it rode the wave in style, actively encouraging or driving some changes, with so many of its attendees involved across disciplines in other areas of science and culture.
The next ScienceOnline, whatever it may be called, will have to catch a different wave. The original never really evolved beyond the time when blogs were new. Blogs were quick and nimble mainly because they were small, with few layers of editorial decision-making. This gave them an unmatched power to respond to events, but has limited their reach. The leaders of online science have gone beyond the blog, exploring many other avenues of creativity. Already, online technologies are making an impact on documentary filmmaking, education, granting agencies, scientific publishing and field research. Interactive video, MOOCs, massive Facebook communities, and live-online hybrid events have pushed the boundaries of science communication in new ways. We are still making stuff -- even knocking on the door of that most hidebound mode of communication, the television news. With these successes, the makers have become leaders in their fields, spreading new approaches and techniques into more specialized communities. Tomorrow's online science conversations must look forward to this diverse future.
Nature last week carried a great article by Barbara Fraser about the growing research into the earliest peoples of South America: "The first South Americans: Extreme living". She followed researchers Kurt Rademaker and César Méndez on their respective fieldwork projects in Peru and Chile.
The landscape looks bleak, but Rademaker views it through the eyes of the people who built a fire in the rock shelter, named Cuncaicha, about 12,400 years ago. These hunter-gatherers were some of the earliest known residents of South America and they chose to live at this extreme altitude — higher than any Ice Age encampment found thus far in the New World. Despite the thin air and sub-freezing night-time temperatures, this plain would have seemed a hospitable neighbourhood to those people, says Rademaker, an archaeologist at the University of Maine in Orono.
“The basin has fresh water, camelids, stone for toolmaking, combustible fuel for fires and rock shelters for living in,” he says. “Basically, everything you need to live is here. This is one of the richest basins I've seen, and it probably was then, too.”
To me, the kind of work being done in South America and in Mexico upon early Americans is really inspiring. Archaeologists are finding many sites that document the human presence in the Americas before 10,000 years ago, including provocative skeletal remains from deep inside of Yucatan caves. The situation in the U.S. and Canada has also changed with the addition of new sites and methods (including paleogenetics). We are at the borderline of a revolution in our approach to the initial habitation of the Americas.
Gorham's Cave is on the eastern face of Gibraltar. It was carved by the sea, and now lies above sea level because of the upthrust of the Rock over hundreds of thousands of years.
I took this photo from a boat offshore, and the one thing it lacks is a convenient scale. The cave entrance soars more than forty meters high.
The Scientist has a nice article about the evolution of trichromatic vision in primates: "The Rainbow Connection". Trichromacy in anthropoid primates is a great example of many evolutionary mechanisms, and I discuss it every semester in my introductory course. New World monkeys have a different mechanism (allelic trichromacy) than catarrhines, and the appearance of the two kinds of trichromacy is a clear example of evolutionary convergence.
The linked article discusses some interesting consequences of allelic trichromacy, which leaves most New World monkey populations polymorphic for color vision -- a mix of heterozygous individuals who are trichromats with homozygous individuals who are dichromats:
Amanda Melin of Washington University in St. Louis has spent years traveling to the forests of Costa Rica to observe capuchin monkeys in their natural habitat. Like squirrel monkeys, these New World primates have dichromatic males and either dichromatic or trichromatic females. Melin spends days at a time watching the animals forage, walking kilometers through the forest as the monkeys move from tree to tree, and collecting DNA from fecal samples, in an effort to determine which colors each animal can see. Much to her surprise, she’s found that fruit feeding rates between dichromats and trichromats are the same, initially suggesting that color vision doesn’t offer an advantage for foraging.
Digging deeper into the data, however, Melin uncovered a subtler effect. “Where we see the difference is in accuracy,” she says. “Trichromats are making way fewer mistakes, but foraging at a more leisurely pace.” Dichromats, on the other hand, appear more frantic, touching, sniffing, and biting more fruits, including unripe or inedible ones. The question Melin is trying to answer now is whether that sloppier foraging behavior has any nutritional impact on the animals.
I also love the accompanying infographic, which emphasizes that many kinds of vertebrates have even better vision than anthropoid primates. Everything from goldfish to chickens see four colors, with sensitivity into the ultraviolet!
The alumni magazine of the University of Wisconsin-Madison has done a great article about my recent massive open online course (MOOC), written by the science writer Jill Sakai: "Behind the Screens". The article introduces some of the team behind the creation of the course, and discusses how we made some of the course's more unique elements:
He assembled a portable video kit and carried it everywhere, recording interviews with experts and lectures at field sites all around the world. He caught colleagues at conferences and at digs, in labs and over beers, and he talked to them about what they do and why, what they’ve learned, and what it means. He sent small cameras into the field with UW students to capture the unique feel of an archaeological site — a mixture of tedium and toil punctuated by flashes of discovery.
Then, working with a team from the academic technology group of the university’s Division of Information Technology (DoIT), he edited dozens of hours of footage into eight units of five- to twenty-minute video segments that were posted on the Coursera site each week from mid-January through mid-March this year.
I have been following up the data we gathered during the course. We saw some remarkable outcomes -- including the global scope of the students, their willingness to assist in evaluating their own learning during the course, and their interactions with each other through discussion forums. I have been inspired by some of the stories students told about their experiences. The outcomes have deepened my commitment to bring the stories of human evolution research out to a global public.
The entire process was enormously time-intensive, and the graduate student TA's were incredibly important to the success of the project. I'm very pleased that Sakai was able to feature the work of the entire team:
In the sea of students, those forums served as a source of community, say graduate teaching assistants Sarah Traynor PhDx’15 and Alia Gurtov MS’13, PhDx’15, with posts ranging from the serious to the lighthearted. “They made a forum called The Pub, and people would go in and chat, [writing], ‘Welcome to the course, grab a beer, and sit down and talk!’ ” says Traynor.
Watching the videos is less like watching documentaries and more like sitting in on real conversations between people who happen to be world-class experts and professional colleagues. Their talks dig into the very roots of the human race.
As many readers have noticed, I have begun releasing some of the videos here on the weblog and through YouTube. I'll continue to premiere these during the next few months, particularly as I have been adding new interviews and films in anticipation of offering the course again sometime in 2015.
Notable paper: Shipton, Ceri, Ash Parton, Paul Breeze, Richard Jennings, Huw S. Groucutt, Tom S. White, Nicholas Drake, Remy Crassard, Abdullah Alsharekh, and Michael D. Petraglia (2014) Large Flake Acheulean in the Nefud Desert of Northern Arabia. PaleoAnthropology 2014:446-462. doi:10.4207/PA.2014.ART85
Synopsis: The authors are part of the University of Oxford Palaeodeserts Project, and they report on the results of survey work in the Nefud Desert of Northern Arabia. They located four sites with Acheulean bifaces, documenting human occupations during wetter climatic phases when large lakes formed in the northern part of the Arabian Peninsula.
Important because: Although later sites representing Middle Paleolithic industries are known from northern Arabia, the earlier time period has so far been represented mainly from the coastal fringe and the Hadramaut. Northern Arabia helps to fill a handax-sized hole between the well-known sites of the Levant and those of India.
But... It is misleading to cast the archaeological problem as one of routes of dispersal to India. There were hundreds of thousands of years at play, small hunter-gatherer bands fluctuating along with the local climates. The comparatively well-watered Levant and Mesopotamia were always connected through Syria and southern Turkey -- the "fertile crescent". That makes northern Arabia a similar case to much of the Sahara, an area that nearby human populations may have raced to exploit during the occasional time intervals when rainfall was higher. A serious area of pulsed exploitation outside of Africa may have figured into gene flow or dispersal through much of Asia, without being a "connection" between geographic regions.