Comparing astronomy to paleoanthropology

5 minute read

Both sciences study rare events that happened a long time ago. Both require interpretations of process, and rely on comparisons between different observed cases -- stars, supernovae, and the like for astronomy, fossils for paleoanthropology.

It would seem that observing astronomical objects and events ought to be freer -- anyone with a telescope can look up and see them, right? But of course, the very distant, very rare, and therefore very interesting events can't be observed with just any telescope; they require special instrumentation, fixed investment in large telescopes and processing computers, and arrangements to share time between different projects on said instruments.

It's sort of the same with humans lately. Anyone can sequence a gene these days, so evidence for human evolution is almost free to anyone. But the very rare, and therefore very interesting, human fossils are difficult to obtain, require specialized facilities and personnel to prepare, and of course require special arrangements to share access among researchers studying them.

So there are some broad similarities. But there are also differences. The comparison occurs to me because of a story from NASA today about the detection of a recent gamma ray burst.

Scientists using NASA's Swift satellite and several ground-based telescopes have detected the most distant explosion yet, a gamma-ray burst from the edge of the visible universe.
This powerful burst was detected September 4. It marks the death of a massive star and the birth of a black hole. It comes from an era soon after stars and galaxies first formed, about 500 million to 1 billion years after the Big Bang.
"We designed Swift to look for faint bursts coming from the edge of the Universe," said Swift principal investigator Dr. Neil Gehrels of NASA Goddard Space Flight Center in Greenbelt, Md. "Now we've got one and it's fascinating. For the first time we can learn about individual stars from near the beginning of time. There are surely many more out there," he added.

Here's the part that interested me the most:

Swift detected the burst and relayed its coordinates within minutes to scientists around the world. Reichart's team discovered the afterglow using the Southern Observatory for Astrophysical Research (SOAR) telescope atop Cerro Pachon, Chile. Over the next several nights, the UNC team used SOAR and the Gemini South telescope, also on Cerro Pachon, to calculate a redshift of greater than 6 using a light filtering technique. A team led by Nobuyuki Kawai of the Tokyo Institute of Technology used the Subaru Observatory on Mauna Kea, Hawaii, to confirm the distance and fine-tune the redshift measurement to 6.29, using a technique called spectroscopy.

So, after detecting the furthest gamma ray burst yet known, they immediately broadcast the news to colleagues around the world to make observations from other stations, depended on the special capabilities of other teams to supplement their observations and provide independent replicates, and integrated those observations into a single picture of the astronomical event.

Paleoanthropology is also collaborative in this way. Research teams are made up of people with many different specialties, and people from outside the team may be drawn in to address special aspects of anatomy, to apply special techniques, or to independently check conclusions. The process appears less public than in astronomy, and it has a much slower response time to new discoveries and events, but then it is also much more poorly funded. Even so, not just anybody is supposed to find out about new stuff, as witnessed by the recent premature announcement of the Kuiper belt objects in the face of internet cracking attacks.

The biggest difference I see between the fields is in the dissemination of results. New results in physics, including astronomical research, are disseminated through arXiv, on which new research preprints are freely available. This system encourages early comment on new research as well as openness about what conclusions are supported by data, and which are more speculative. As an ideal, it encourages a scientific hierarchy based on ideas rather than data access. This is because its entire existence is about communicating ideas more quickly to those equipped to evaluate them.

The arXiv does not replace traditional journal publication in physical sciences; instead, journal publication remains highly important for peer review, provision of an imprimatur of quality, and status. There are suggestions that arXiv should itself begin to incorporate peer review of high-traffic articles, as a step toward ensuring the long-lasting utility of certain papers. But even lacking this, the utility of the arXiv service is clear: ideas are available for scrutiny long before they appear in journals.

Without as strong a tradition of circulating results, paleoanthropology is at a comparable disadvantage when it comes to quality of science. We have a long history of retractions. This is not necessarily bad; indeed, I would say that our research results ultimately undergo a much higher degree of scrutiny than most in the physical sciences. It is the truly exceptional gamma ray burst that gains as much attention as a new hominid fossil. But this heightened scrutiny takes years, when the basic issues might be sketched out in weeks with a faster mode of communication.

Is it only a matter of time before paleoanthropology moves in this direction? That is difficult for me to say. There is no institutional incentive at present for people to share their research. The Paleoanthropology Society has already begun making dissertations available for download -- a sort of mini-arXiv for theses, with participation voluntary. Since 2003, there has been a section of arXiv devoted to quantitative biology, the intersection between mathematical sciences and biology. This includes research devoted to populations and evolution, and I have been following the submissions for some time. So the infrastructure for such a system is not far away -- it is well within the capabilities of a single university, department, or organization.

But without the social expectation of communicating results quickly, there is really no force that can drive people to change. Graduate students are enculturated into a cult of secrecy -- sometimes the hard way as someone else steals their results or yanks their access to specimens. Entire books are published with factually wrong information because no outside professionals read them in advance.And new ideas from cranks get just as much attention as new ideas from established scientists, because the press cycle gives too little time to distinguish the two.

The lesson I draw from astronomy is that these problems are not inherent to the study of rare events, expensive analysis, or historical phenomena. They are symptoms of a social disorder.

I increasingly find that openness works. I get far more insightful peer review on what I write for free here, than on anything I have ever submitted to a journal. And it's instantaneous. I don't write scholarly review articles here, and I don't give out any research results. There's no incentive for it, and there's a positive disincentive in the likelihood of a high-ranking journal turning down previously published material. But if an incentive were available -- with credit for a tenure record -- I would start.