2630: Shuttle Skeleton

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Shuttle Skeleton
It's believed to be related to the Stellar Sea Cow.
Title text: It's believed to be related to the Stellar Sea Cow.


The Space Shuttle was a reusable spacecraft system used by NASA from 1981 to 2011, after which it was decommissioned. In this comic, Randall suggests that the nature of the shuttle was in doubt or misunderstood until either an intact 'specimen' (of which there are four) had been dissected, or possibly the remains were reassembled from the two that were lost in accidents.

With its shape, shown in the small image, and the tail fin, it looks a bit like a bony fish or ray. The joke is that after the shuttle was taken out of use, its skeleton was analyzed, and as shown in the comic, was found to have a skeleton typical of a mammal, with details such as the pentadactyl quadripedal bodyform hidden beneath its aerodynamic sweep, as well as having bones (i.e., not primarily cartilage). This morphology is similar to that possessed by a whale. However, it should be noted that the skeleton has several features not found in mammals, e.g. the ribcages extending all the way to the pelivs and past the shoulder these features are more reminiscent of snakes. Of course, the skeleton of a spacecraft is not made of bones, but rather of metal and other manufactured materials.[citation needed]

As the understanding of the natural world developed, many taxonomic misconceptions were overturned, or at least the scientific terminology was tightened. For instance, it was found that dolphins and whales were mammals, not fish.[cetacean needed] Because of convergent evolution – the tendency for distantly-related species to adapt similarly to a given environment – it is often not easy to properly classify organisms merely by observing their exterior. For example, whales and fish have very similar body shapes, as did the extinct plesiosaurs, because life as a swimming vertebrate favors the same adaptations. In lieu of genetic analysis, or even of sufficient observation of them in the wild, the main progress in understanding differences among marine animals was often in dissecting the corpses of creatures found stranded or caught in nets, or reconstructing them from skeletal remains. Together with fossil evidence, insights were developed about their origins and differences from others' origins.

The title text conflates the now-extinct Steller's sea cow, an aquatic mammal related to manatees and named after explorer/zoologist Georg Steller (also extinct), with the adjective "stellar", which means being of a star or stars, such as inter-stellar space or stellar masses. While this conflation is often done accidentally, due to the name Steller being much rarer than the adjective "stellar," in this case it is probably an intentional pun.

One might expect that the idea for this comic may have come from the recent California Appeals Court ruling that bumblebees are considered fish under a law which categorized several other invertebrates as part of a broad colloquial category of fish (as in "Fish and Game Department" designations.) However, given the short time between the ruling and the comic's release, it is likely that this was a coincidence.

The comic also prominently conflates biology with artifice, a budding and controversial concept in these times of rapid AI use and research.


[In the upper right part of the panel there is a small drawing of the Space Shuttle as seen from above. Beneath it, and to its left, is a much larger drawing with the same outline as the Shuttle. But this time the outer layers have been removed to reveal the inside. This has revealed a skeleton taking up the entire space inside. The head is in the front, and legs and tail at the rear, with arms and fingers in the wings, looking somewhat like a bat's "hand/wings". The bones are white with the frame of the shuttle gray or black. Some of the lines outlining the design of the shuttle are both on the small and the large drawing, along the wings and rear engines. Both feet and arms have five fingers/toes. There seem to be 24 ribs in the very long rib-cage.]
[Caption beneath the panel:]
The Space Shuttle was long assumed to be a type of fish or shark, but after it was decommissioned in 2011, analysis of its skeleton determined that it was actually a mammal.

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Well, I know what "paint job" I'm putting on the pirate shuttle, in my next TTRPG session.
ProphetZarquon (talk) 13:12, 8 June 2022 (UTC)


The joke here is about a recent California court case (https://www.cnn.com/2022/06/06/us/california-bees-fish-court-ruling-scn-trnd/index.html) which declared bumblebees to be considered fish under the California Endangered Species Act. The definition of "fish" listed in the act included invertebrates, which is why skeletons are relevant. Clam (talk) 14:36, 8 June 2022 (UTC)

I don't know if this comic is related to the bee/fish ruling or not. There have been many earlier works where the skeleton of a fictional person or creature has been shown (the Simpsons, Lego man, etc). SDSpivey (talk) 17:14, 8 June 2022 (UTC)

Could someone explain why this is a mammal skeleton and not say, something related to a crocodile or a bird? Currently there's only a hint what makes it look like one. Which doesn't say that much to someone who doesn't know mammal skeletons too well. TIA! Chichak (talk) 17:09, 8 June 2022 (UTC)

That's a good question, since there are lots of skeletal analogues among all the vertebrates. Crocodiles and birds only have 4 toes on their rear legs, so that could be part of it. It may just be an overall resemblance to whales, which we already know are mammals. Barmar (talk) 18:06, 8 June 2022 (UTC)
Well it definitely wouldn't be fish. -- Hkmaly (talk) 18:36, 8 June 2022 (UTC)
I'm actually confused about this. Mammals do not have ribs going all the way to the hips. Those look more like reptile ribs. 23:30, 8 June 2022 (UTC)
The head of this shuttle looks a lot more like a whale's head, specifically a toothed whale like a sperm whale. The arms are closer to the paddle-like structure of whale arms, but much longer, to be able to form the wings and control surfaces at the back. Having the ribs continue all the way to the pelvis, like a snake, would be an adaptation to give structure to the cargo doors, but that would likely impede their ability to open. Also, I do not know of any mammal that have ribs above the shoulder blades. The clavicles should be there Nutster (talk) 16:28, 9 June 2022 (UTC)
Those are extended transverse processes of the cervical ribs, or at least that's how I interpreted them. Note that the transverse processes are evolutionary descendants of what were ribs in an ancestor. Nitpicking (talk) 17:51, 9 June 2022 (UTC)
To me, there's definite impression of a bat skeleton, most notably that the fingers are hugely elongated to become the formers for the wings and the legs/feet are small enough to be nearly useless for anything more than basic gripping. 16:08, 11 June 2022 (UTC)

These "citation needed" tags are getting ridiculous, but I do wonder about whether any space craft had plastic parts. Metal, yes. Carbon fiber, yes. Plastic? I doubt it. SDSpivey (talk) 17:14, 8 June 2022 (UTC)

They SHOULD be ridiculous, so good job. Regarding the question, I guess space craft may have plastic cup holder for example. The plastic parts are unlikely to be on outside, but inside, why not? In Apollo 13, they were using plastic bags for something at least. -- Hkmaly (talk) 18:36, 8 June 2022 (UTC)
I was just thinking about the skeleton, you're right. SDSpivey (talk) 22:08, 8 June 2022 (UTC)

This comic was unexpectedly terrifying. Not sure what I expected, but it wasn't this. 20:43, 8 June 2022 (UTC)

I was just reading D'Arcy Thompson's "On Growth and Form". (John Tyler Bonner's 1969 abridgement of the 1942 edition.) At the end of the book, Thompson draws skulls on a grid, such as an early ancestor of the horse, Hyracotherium, and then distorts the grid in a uniform way to produce a new sketch that resembles a related species. He then used the same technique to demonstrate that other species were not "missing links" between those two species, because he could not distort the grid to make them fit. Tanana (talk) 02:41, 9 June 2022 (UTC)

I'd be very wary of someone using a form of personal incredulity to demonstrate something (c.f. the "junkyard+tornado->jumbo jet" 'counter-'argument). I'm not aware of the book, but it sounds like it's anti-evolution, by your telling of it, and picking a case where you can 'find' a simple distortion that works across two examples doesn't then invalidate the intermediate stages for which there's no reason to believe a consistent evolutionary pressure would create similarly smooth transitions at all stages you get to observe. It's observing the end-points of a random-walk and then being surprised at where the walker has managed to visit along the way. The term "missing link" is also outdated (those who use it these days tend to then require additional missing links be found betwixt any now-found 'links' and their neighbours, rather than ever be usefully satisfied) but I suppose might have still been a bit more mainstream back in 1942.
So sounds like a fun book to read (I like a good cryptozoology/gods-were-aliens book, too!) but I'd be wary about it not having aged well (as I would with bits of the Origin Of Species, though it has held up surpisingly well), and I hope you're also reading it in a suitable frame of mind and not taking it (or passing it on) at face-value. 09:04, 9 June 2022 (UTC)

Yes, the book (On Growth and Form) is certainly dated in places (first edition was in 1917). But I wouldn't characterize his arguments as being completely anti-evolutionary. It's just that he notices many instances where the physical forces on organisms seem to be directing the form of the organisms. He doesn't explain the exact mechanism of change. (At least in the abridged edition.) He's pretty searchable with Google Images. Tanana (talk) 20:36, 9 June 2022 (UTC)

Maybe search when I can spare time. Sounds a bit Lamarckian, too... ;) 23:04, 9 June 2022 (UTC)

By way of explanation, I think I thought of D'Arcy Thompson because of his strong emphasis on how physics and mechanics (could) contribute to biological forms. Mr. Munroe seems to be playing with some of the same ideas. Tanana (talk) 03:50, 10 June 2022 (UTC)

Well that's horrifying. TheLonelySandPerson (talk) 01:39, 9 June 2022 (UTC)

On a related note, the Apollo Lunar Module was a completely different design early on, but slowly evolved into its familiar crab-like shape through convergent evolution. 03:14, 9 June 2022 (UTC)

Carcinization strikes again. 07:25, 9 June 2022 (UTC)

What’s up with the “type of fish or shark”? Sharks are a type of fish, the “or shark” doesn’t make sense?

Presumably Randall was thinking "bony fish". Maybe that was too technical to be funny. Nitpicking (talk) 12:44, 9 June 2022 (UTC)
((Edit conflict, and I'm really just expanding upon Nit's summary, but having written it now, here you are...)) It's messy, but often sharks are (paraphyletically) kept out of the "fish" category. Similarly to how mammals, amphibians, etc of the tetrapoda are actually descended from the "fish" superclass (under its classical branch name, of course). Thus to separate from the bony-fish (and possibly other subtrees, across which the common term "fish" might alply), sharks may be deemed not-fish for classification purposes and it is often good practice to do so.
Common names confuse matters: a dogfish (shark) is very far related from a starfish, at least as much as a seahorse is more fish (very so, in fact!) than equine. 12:54, 9 June 2022 (UTC)
If bees can be classified as fish, then so can sharks! But wouldn't be easier to just expand the definition of endangered species to include invertebrates, rather than lumping things clearly where they do not belong? But, hey, what do I know? I am just a scientist, not a lawyer. Nutster (talk) 16:21, 9 June 2022 (UTC)

Just for clarification, a California court has not ruled that bees are a type of fish. They ruled that when a law specifically states "for the purposes of this law, X includes Y," it means that for the purposes of that law X includes Y. 16:58, 9 June 2022 (UTC)

It's very like the old "Beavers are fish, for the purpose of eating at Lent/etc" from the Catholic church. Except that I presume they aren't effectively encouraging the eating of bees/fish, in lieu of anything else... 18:53, 9 June 2022 (UTC)
Yep, Catholics can now eat beaver, capybara, or bees on Friday. But not Space Shuttles. 20:13, 9 June 2022 (UTC)

Hello, I've replaced the CNN video with an NBC archive video because the CNN video is georestricted to US only (You can check restrictions using https://polsy.org.uk/stuff/ytrestrict.cgi, checking https://www.youtube.com/watch?v=AfnvFnzs91s returns a nearly-red map except for the US). - 18:42, 9 June 2022 (UTC)

I've gotta say this is the most confusing skeleton I've seen. It's certainly a vertebrate (spine? check. skull? check), and it's certainly at least a tetrapod (girdles? check. 1 proximal limb bone, two distal limb bones per limbs? check.), and definitely at least a basal reptile. However, it is correct that mammals (modern synapsids) don't have ribs going down to their hips. Additionally, if those holes in the top of the skull are supposed to be the temporal fenestrae, those are the highest-placed temporal fenestrae I've seen on a synapsid. Usually they're much lower (as an example: in a human, our temporal fenestrae are the space under our zygomatic arch - our "cheekbone," though in all fairness humans are actually poor examples of many things in synapsids). Also, the lack of a third phalanx on any of the digits is throwing me for a loop; I'm sure there are mammals that lose some phalanges on all digits, but for the life of me I can't think of one (even a horse has all three phalanges on the one digit they keep). TL;DR: this skeleton looks more like that of a diapsid reptile than a mammal, in my opinion. (My only qualification is that I have a masters in biology, and, for a year or so, I studied under a paleontologist who specialized in the split between diapsids and synapsids) 18:45, 10 June 2022 (UTC)

I believe those are the eye sockets. The temporal fenestrae would have to be below them, and largely hidden from the top view. A side view would probably have made identification easier.DL Draco Rex (talk) 18:04, 12 June 2022 (UTC)

I provided the requested citation concerning Georg Steller's extinction, so I removed the "Citation Needed". These Are Not The Comments You Are Looking For (talk) 02:59, 12 June 2022 (UTC)

I would have linked to his Wikipedia page, myself, for general wikisolidarity/not-having-the-padlock-icon, but probably a matter of taste... ;) 10:46, 12 June 2022 (UTC)