2418: Metacarcinization

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Scientists still don't know how marine biologists manage to so consistently bring up whalefall ecosystems, when relevant conversational openings are so few and far between.
Title text: Scientists still don't know how marine biologists manage to so consistently bring up whalefall ecosystems, when relevant conversational openings are so few and far between.


The comic strip opens with a conversation between White Hat and Cueball as they are walking together. White Hat asks Cueball if he has seen a video of a crow sledding on a roof — presumably this one, or one of its later viral reposts. (Animals sledding seems to be a thing lately). In this case, the crow is a Hooded Crow. Cueball remarks that it's a cool example of tool use by animals, a sign of intelligence (which corvids [Corvidae; the crow family], including crows, ravens, and jackdaws, are famous for). He then points out that sea otters use tools too, namely using stones to crack open crab shells.

This in turn leads him to bring up the fact that the 'crab' body plan has evolved multiple times, a phenomenon known as carcinization, previously discussed in 2314: Carcinization. In that strip, Cueball turned into a crab shortly after hearing about carcinization, so perhaps White Hat will likewise be transformed momentarily.

The conversation serves as an example of a wiki walk, where a conversation naturally diverts from the original topic into a seemingly unrelated topic through a series of logical associations. Although a sledding crow has little to do with carcinization in and of itself, the conversation has managed to bridge the two topics through intermediary steps (crow using a sled, animals using tools in general, otters using stones to open crabs, crab evolutionary process).

The title and caption is a joke that, much like natural life-forms have evolved into crab-like forms multiple independent times, so too do all of Cueball's (or Randall's) conversations wiki-walk into a discussion of that evolutionary process.

In the title text, Randall jokes that marine biologists have a similar tendency to bring up whalefall (or "whale fall") ecosystems, which arise whenever a whale's carcass falls onto the deep ocean floor and are thought to provide "stepping stones" for species migration across the generally barren seafloor. Such occurrences are relatively rare, perhaps occurring once every few miles on whale migration routes, but they happen anyway, much like conversations about them. Another example of scientists tending to bring up facts from their field of study can be found at 1610: Fire Ants, and Randall often brings up the fact that birds evolved from dinosaurs.


[White Hat and Cueball are walking together. White Hat has his smartphone out in his hand.
White Hat: Have you seen this video of a crow sledding on a roof?
Cueball: Yeah! It's always cool to see animals using tools.
Cueball: Like how sea otters use rocks to open crab shells.
Cueball: Hey, did you know the "crab" body plan has evolved multiple times?
[Caption below the panel:]
Regardless of the starting topic, any conversation with me eventually converges to carcinization.
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Up until the moment I opened the video, I read every instance of "crow" in the comic and explanation as "cow"... Was a bit disappointed by the video! 19:39, 29 January 2021 (UTC)

I think the crow in the video is actually a hooded crow (Corvus cornix) rather than a jackdaw... 20:39, 29 January 2021 (UTC)

Good catch. 20:58, 29 January 2021 (UTC)

I think the crow in the video needs more training. Seems she's not really sure how the sledding works. -- Hkmaly (talk) 01:04, 30 January 2021 (UTC)

Coincidentally, I just heard about a pet/tame duck (called 'Duck') who is regularly bodysurfing with their human in Australia. No idea where crabs come into that. They've probably been eaten by the sharks, or poisoned/envenomated by almost every other creature in and around Australia. 04:34, 30 January 2021 (UTC)

hey! some of the sheep aren't! Helpimstuckinahole smith (talk) 05:47, 31 January 2021 (UTC)

Tool use is another trait that has independently evolved multiple times, in insects, cephalopods, fish, reptiles, birds, and mammals, presumably because it’s so useful. 06:36, 30 January 2021 (UTC)

Have a read of "Are we smart enough to know how smart animals are?" by Fran de Waal (W.W. Norton)

I too independently evolved into talking about carcinisation constantly. Hm. 00:12, 31 January 2021 (UTC)

Speaking of carcinisation, did you know that Squat Lobsters are a thing? These Are Not The Comments You Are Looking For (talk) 23:52, 31 January 2021 (UTC)