How bad images rob science (and good ones don’t)
Paleontologists: honk if this has happened to you. A one-of-a-kind fossil is discovered in “Eastern Mozamberia.” Rumors fly at conferences about its importance and everyone eagerly awaits the publication that will introduce it to the world. Years pass. Still waiting. The scientist who is sitting on the data is notoriously tight-lipped and won’t let anyone see the raw material. Then a paper is published with tantalizingly scant imagery. Crude line drawings are all that are shown. And that is how the literature stands for decades. In one scenario, no one is allowed to see the specimen in person and no further papers are released. In another, the specimen is actually lost and the only record of it is the few pages of published analysis, which sadly raises more questions than it puts to rest. Including it in your analyses is mandatory because of the significance of the fossil, but the data provided – a line-drawing or two – is just not sufficient to make heads or tails of what’s going on in the fossil. So their reconstruction sits awkwardly in your cladogram and clouds discussions. Frustrating!!!
On the other end of the spectrum is a situation like that surrounding Darren Naish’s interesting post on Tetrapod Zoology titled You Have Your Giant Fossil Rabbit Neck All Wrong. In it, he’s responding to the Quintana et al. paper (ref below) on Nuralagus rex, a giant fossil rabbit from the island of Minorca (Spain).
I had a sneaking suspicion that it was the illustration that initially caught Naish’s eye and alerted him to the funny neck posture, so I asked him. And? You betchya, it was. As beautifully as the illustration conveyed the size and skeletal reconstruction of the beast, something didn’t sit well with him in the way they positioned the rabbit’s neck. Naish and colleagues have done a fair amount of work on neck posturing (see Taylor et. al, 2009 or his accompanying TetZoo post) and he theorizes that rather than having a straight neck as shown in Köhler’s reconstruction, Nuralagus would more likely have had an s-shaped neck.
To further illustrate the point, he includes two x-rays of extant rabbits to show the extreme curve their necks make. I cannot weigh in on the veracity of either position, but the visual argument Naish makes is compelling.
But more important than who is right and who is wrong in this situation is the clear fact that this conversation could never have happened without the impeccably clear images that Quintana et al. included in their paper on the giant bunnies. Perhaps they were actively postulating that Nuralagus indeed had a straight neck. Or, perhaps the straight neck represented an assumption held by Köhler that she and her colleagues did not explore (I’ve mentioned before that every illustrator brings a set of assumptions to each drawing they start – it’s impossible not to). In either case, the clear presentation made it possible for an expert in neck posture to come forward and present a compelling argument for a curved neck. An insecure person might shy away from this response and take it as unwelcomed criticism of their work. But I would argue that this is science at it’s best. It’s a collaborative, ever-changing conversation aimed at constantly improving our knowledge.
Quintana, J., Köhler, M. & Moyà-Solà, S. (2011). Nuralagus rex, gen. et sp. nov., an endemic insular giant rabbit from the Neogene of Minorca (Balearic Islands, Spain) Journal of Vertebrate Paleontology , 31, 231-240
Taylor, M., Wedel, M., & Naish, D. (2009). Head and Neck Posture in Sauropod Dinosaurs Inferred from Extant Animals Acta Palaeontologica Polonica, 54 (2), 213-220 DOI: 10.4202/app.2009.0007
Vidal, P., Graf, W., & Berthoz, A. (1986). The orientation of the cervical vertebral column in unrestrained awake animals Experimental Brain Research, 61 (3) DOI: 10.1007/BF00237580