Cheetah anatomy: going digital is not enough

In their comments to a previous post, a couple of friends called my attention to an illustration of cheetah anatomy published in the November issue of NG magazine. I had missed that issue when it appeared, but have caught up now. These friends point to some anatomical errors in that representation, including among the most serious the following: 1) the lumbar vertebrae are in reverse (front side pointing backwards); and 2) the humerus (arm bone) is also reversed. I have found other equally alarming errors, for instance: the animal has 5 instead of 7 cervical (neck) vertebrae, with the last 3 reversed; and the shoulder blades have the wrong morphology, and they either belong to a different species or to a badly pathological individual. These mistakes go against the very anatomical adaptations that the figure captions are highlighting (an animal whose bones were assembled like this would not be able to walk, not to mention run at high speed!!), and one wonders how such errors could happen. I have read the account by NG staff of how the image was created, in an extensive blog post which you can check here:

Now this is an interesting story because it points to the huge potential of 3D imaging technologies but also to the dangers if one puts too much faith in them!

As you can gather from the NG blog post, they scanned all the bones of a cheetah skeleton, making clear their intentions to use all the necessary resources. Great!. Then they put an intern in charge of assembling the whole skeleton in 3D in the computer, and here is where the problems started. The intern got most bones roughly in their right place, but for an illustration like this one, where anatomical accuracy is the whole purpose of the thing, “most of them roughly in place” is clearly not enough.

A nice mount of a cheetah skeleton is exhibited in the Natural History museum in Paris, and it is almost exactly in the same pose as the NG illustration. This one has the bones in the proper anatomical positions, and it is a good model against which to check the  accuracy of the digital image. You can check it in this link (actually a review of the beautiful book “Evolution”, where a photo of the mount was published):

The fact that the bones were scanned and not drawn or modelled by an artist probably gave the editors a sense of confidence about the accuracy of the result, and that is justified as long as the morphology of the individual bones is concerned (assuming that every bone that is in the box belongs to the same animal, which some times is not the case: curatorial errors also occur!). Such overconfidence in the results may lead to undue relaxation of the reviewing process. It is wrong to just sit back and relax, trusting that the machine has done everything right for us. We still need someone with a real knowledge of carnivore osteology checking, bone by bone, the anatomical position and accuracy of each element. It is all right to have clever machines working for us but we should remember that they are and will remain just that –machines!

For me as a cat enthusiast and a passionate student of felid adaptations for many years, the painful side of all this is that I get the impression that too little attention is paid to the real animal in the whole process of creating an image with a huge potential to disseminate the anatomy of this beautiful cat. An enviable amount of resources have been used, but I miss more real passion for the cats themselves!

Finally, a picture:  a comparison between the gallop of a zebra and that of a cheetah, in a nice photo taken by my son Miguel last year in Kenya. You can be sure that the bones that support this amazing cheetah from inside were not assembled like those in the digital image commented above!!!



Posted on 04/02/2013, in Uncategorized. Bookmark the permalink. 2 Comments.

  1. Here Here!

    As a scientific illustrator myself, I get upset with publications like NG that seem to be dropping the ball with their illustration work. Instead of hiring qualified individuals at the prices they deserve, they are tossing jobs to underpaid interns who don’t have the knowledge to do the job right. And its seems like computers are the excuse.

    I work digitally for the most part and I don’t see why working digitally has become and excuse for hastily executed work. Of course, there is an art director at NG who gave the green light to that illustration…. so the poor intern isn’t completely to blame.

    If I had a job within NG, even an internship, I’d work my ass off to ensure the greatest possible accuracy and integrity. It’s national geographic! everyone knows you look at the illustrations first before you read the articles. And it is perhaps the highest profile gig that a science illustrator can get these days when considering exposure to the general population.

    What happened to the days of John Dawson, Dugald Stermer, Barron Storey, and Kazu Sano? MASTERS of their craft, all.

    P.S I’m Huge fan of your work!

  2. Thank you very much for your comments Ben!. My impression is that the intern in charge of assembling the cheetah skeleton was not working directly for NGM, but for the company that was hired to do the graphics. I am not even sure that this graphic has been less expensive than if they hired a specialist to do it, for one thing the company doesn’t look cheap to me judging by their internet profile. Wat I do see is a lack of passion or real interest on the subject matter. For me this is a general problem of the industry that creates graphics for educational science, the job is seen as just business by many of the professionals involved, and the scientists who have to review the results often do it half-heartedly because they don’t care too much about popular science -it is actually seen as an inferior activity from some academic circles. So, in the end it is up to some inndividuals to fight an uphill struggle to keep the standards high. Or so it seems to me.

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