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Talk:3204: Dinosaurs And Non-Dinosaurs

2026-02-12T11:07:48Z

82.132.238.7:

I don't think that's a stork. My guess would be that it's a heron.
The bird in the lower right also looks like some sort of shorebird, but I've got no clue. {{unsigned ip|99.26.146.61|19:45, 6 February 2026 (UTC)}}

:I changed egret to heron. If there is some distinguishing feature in the outline that makes it clear that this an egret, as compared to the more general heron, please document (either in explanation or comments). [[Special:Contributions/107.77.205.200|107.77.205.200]] 19:02, 7 February 2026 (UTC)

I feel like this comic should be in the explanation https://xkcd.com/1211/ [[Special:Contributions/2600:4041:2E5:B900:66D3:74AD:D92D:356B|2600:4041:2E5:B900:66D3:74AD:D92D:356B]] 20:36, 6 February 2026 (UTC)

Could it have a brief layman's explanation of how/why the top right *aren't* dinosaurs? Y'know beyond just "well, technically..." [[Special:Contributions/91.84.189.119|91.84.189.119]] 06:52, 7 February 2026 (UTC)
:They are not dinosaurs because dinosaurs are only a subgroup of prehistoric animals living on land. Others are flying or underwater reptiles (don’t know the real names of those), or just plain reptiles who have existed (as a group) for far longer. Dinos are technically named „land reptiles“, but are not reptiles. It’s a bit confusing and this is where my half knowledge ends [[Special:Contributions/2A00:1E:82C2:D401:F4A3:23F3:8A2D:63B1|2A00:1E:82C2:D401:F4A3:23F3:8A2D:63B1]] 09:33, 7 February 2026 (UTC)
::Saying “dinosaurs are not reptiles” isn’t true, but more importantly is a strange thing to say in a scientific context. If you are using “reptile” informally, then the definition of one is fuzzy anyways. If using it cladistically, then reptile pretty much means “sauropsid” which includes dinosaurs and thus birds, which are not informally/traditionally included, so you might as well use the less ambiguous term “sauropsid”. [[User:Terdragontra|Terdragontra]] ([[User talk:Terdragontra|talk]]) 15:46, 7 February 2026 (UTC)
:::Yeah, the common definition of reptiles doesn't match a single evolutionary group, as crocodiles are more closely related to dinosaurs, and thus birds, than they are to lizards. Turtles separated earlier, so are equally related to both of those groups. To answer the original point, dinosaurs are defined as all the animals descended from a certain common ancestor, which they only relatively recently realized includes birds, and not just some long extinct animals known only from fossils. There are aome other animals also known only from fossils in the same time period that the general public often mistakenly thinks are dinosaurs, but are not closely related to them, being closer to other groups of living animals.--[[Special:Contributions/2600:100A:B12D:723E:FCD9:2B70:1145:6A44|2600:100A:B12D:723E:FCD9:2B70:1145:6A44]] 07:26, 8 February 2026 (UTC)

Did anyone else think that "Pseudo-such" things were a made up thing for staplers? [[User:Kev|Kev]] ([[User talk:Kev|talk]]) 13:36, 7 February 2026 (UTC

I’m interested at the things somewhere on the boundaries. Some basal forms are sometimes included as dinosaurs and sometimes just outside the clade. And som nonbird dinosaurs are somewhat birdlike, and shoebills feel more dinosaury than the average bird (while hummingbirds feel less so). [[User:Terdragontra|Terdragontra]] ([[User talk:Terdragontra|talk]]) 15:48, 7 February 2026 (UTC)
: The bird which feels the most dinosaury to me is definitely the cassowary. I think Randall could have included it in the top-left quadrant. [[User:Martin|Martin]] ([[User talk:Martin|talk]]) 22:11, 8 February 2026 (UTC)

What bird is in the lower right of the Are dinosuars, but don't seem like dinousaurs box? Currently the explanation says "falcon" - not clear why somebody thought it was a falcon. Whatever ID we give, should have some explanation. The wings look not as long front to back as a falcon. It also lacks a falcons spread tail (which can be tucked in or course). Also lacks the hooked beak typical of a falcon.
The long narrow wings suggest a relatively long distance flyer. It lacks the split tail typical of a swallow or swift. The beak isn't long enough for an albatross or similar. Gulls typically have bigger beak and rounded head. A {{w|petrel}} is my current best guess. A tern, shearwater or skua also seem possible. [[Special:Contributions/107.77.205.200|107.77.205.200]] 19:36, 7 February 2026 (UTC)
:I would have gone with describing it as a generic gull. Which would be wrong, in its own way, but at least not as wrong as 'seagull' ;) [[Special:Contributions/81.179.199.253|81.179.199.253]] 20:46, 7 February 2026 (UTC)
: The short neck is falcony though. I just googled "birds of prey silhouettes" and falcon looks very plausible to me. [[User:Martin|Martin]] ([[User talk:Martin|talk]]) 22:16, 8 February 2026 (UTC)

There is a claim bicycles are not living creatures, but I think we may need a citation. Policeman MacCruiskeen. [[Special:Contributions/80.41.29.9|80.41.29.9]] 14:54, 8 February 2026 (UTC)

Continuing with the profile pedantry, in the objects which are neither dinosaurs nor look like dinosaurs, that is definitely not a pineapple. Pineapple leaves do not have a central stem, but rather all originate from the top of the pineapple. It more closely resembles a bonsai pine tree in a pot. {{unsigned ip|1.141.51.6|06:22, 9 February 2026 (UTC)}}
: It's a toilet brush put away the wrong way up. [[Special:Contributions/82.13.184.33|82.13.184.33]] 10:35, 9 February 2026 (UTC)
::I believe it is indeed a pineapple, but rather stylized. I searched up a large selection of silhouette and line-drawings of pineapples, and many of them looked much like this example. Randall may have cribbed a bit from the existing corpus of work, rather than a real-life fruit? I don't know. A pineapple seems like the zany kind of object that would land in one of these round-ups, rather than a bonsai or toilet-brush, don't you think? [[User:Elizium23|Elizium23]] ([[User talk:Elizium23|talk]]) 09:23, 10 February 2026 (UTC)
:::I'd say an upside-down toilet brush is a lot zanier than a pineapple. [[Special:Contributions/82.13.184.33|82.13.184.33]] 16:10, 10 February 2026 (UTC)

This comic is basically just one big set-up for Randall's amusement that a stapler looks a bit like a crocodile, isn't it?[[Special:Contributions/82.13.184.33|82.13.184.33]] 10:29, 9 February 2026 (UTC)
: Sounds legit...especially as I first thought it WERE a crocodile :-) {{unsigned ip|2a02:2455:1960:4000:9da4:59d7:1b5a:dcc3|12:37, 9 February 2026 (UTC)}}

The squirrel and stapler in the bottom right square reminded me of Squirrel Stapler lol [[User:Amateurautist|Amateurautist]] ([[User talk:Amateurautist|talk]]) 16:25, 9 February 2026 (UTC)
"Pot plant?" We can't see it well enough to be that specific, though I think it is shaped differently than a pot plant. "Potted."
Anyway, I saw a pineapple, not a pot(ted) plant. [[Special:Contributions/2607:FB91:5103:C3E:1873:B450:305A:44C9|2607:FB91:5103:C3E:1873:B450:305A:44C9]] 18:08, 9 February 2026 (UTC)
:In some parts of the English speaking world they call plants in pots "a pot plant" rather than using the term to refer to the reefer.[[Special:Contributions/57.140.28.52|57.140.28.52]] 17:42, 11 February 2026 (UTC)

If we are going to be pedantic, the flightless bird silhouette is of a false penguin, not a penguin, although admittedly today people call false penguins “penguins” because all the true penguins were exterminated about 180 years ago. [[User:John|John]] ([[User talk:John|talk]]) 04:46, 10 February 2026 (UTC)

We've linked to ''{{w|Jurassic Park}}'' as one of Randall's favorite films, but since it was first a most excellent Crichton novel, and then an entire media franchise, isn't it fair to say that Randall is a fan of the whole thing, rather than just the one film? Do we have an actual citation where he mentions it? [[User:Elizium23|Elizium23]] ([[User talk:Elizium23|talk]]) 09:20, 10 February 2026 (UTC)

I don't think the category titles in the description should say "creatures". Nothing in the comic specifically claims these are groups of creatures, and the items in Quadrant IV include a bicycle, a stapler, and a plant or pineapple, which are clearly not creatures. [[Special:Contributions/136.226.19.189|136.226.19.189]] 17:57, 10 February 2026 (UTC)
:If you'd kindly consult a dictionary, you would see that this definition of "creature" is perfectly normal and understandable. While Randall doesn't use it directly, it may be too archaic for the audience here to understand. I wouldn't oppose changing our wording, but I just wanted to point out that it is, pedantically correct usage after all. [[User:Elizium23|Elizium23]] ([[User talk:Elizium23|talk]]) 00:54, 11 February 2026 (UTC)
::I highly doubt that his intention was an ''archaic'' definition that has fallen out of favor. The more correct term in the present day would be "objects", not "creature". I say that we change it to objects. [[User:42.book.addict|tori :3]][[User talk:42.book.addict|talk to me!]] 00:58, 11 February 2026 (UTC)
:::I object. "Objects" objectively gives a sense of "non-creature", so "object" not "creature" would project a reach in itself.
:::There's 16 (or 17) drawings of truly "creatures", and 2 (or 3) drawings of truly "objects", depending upon what the maybe-pineapple is and whether you want to class the person by one of the words or not. Either of those words is going to be awkward (one less overhelmingly than the other), and neither is really the kind of common-parlance hypernym that wouldn't go without complaint. You need something like "entities", really.
:::So... we could always go for the even more descriptive (and suitably inclusive, in-context) "''silhouettes'' that [don't] seem like dinosaurs" and that "are [not]"? Even Cueball is a silhouette of a regular (circle-outline for head) Cueball. As a suggestion. [[Special:Contributions/81.179.199.253|81.179.199.253]] 01:29, 11 February 2026 (UTC)

So Linnaeus had information animal, vegetable, and mineral? [[User:Chrullrich|Chrullrich]] ([[User talk:Chrullrich|talk]]) 10:57, 12 February 2026 (UTC)
:He was very well acquainted, too, with matters mathematical. [[Special:Contributions/82.132.238.7|82.132.238.7]] 11:07, 12 February 2026 (UTC)

3205: Carbon Dating

2026-02-12T10:58:17Z

82.132.238.7: /* Explanation */

{{comic
| number = 3205
| date = February 9, 2026
| title = Carbon Dating
| image = carbon_dating_2x.png
| imagesize = 250x348px
| noexpand = true
| titletext = This dating is corroborated by the presence of stone tools at the site, rather than earlier and less effective helium ones.
}}

==Explanation==
{{incomplete|This page was created recently by a SPEAR MADE OF FREE ELECTRONS. Don't remove this notice too soon.}}
{{w|Carbon dating}} is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of {{w|carbon}}. This method is commonly used by {{w|archaeology|archaeologists}} and is invaluable in terms of estimating the point in time a piece of organic matter (such as a fossil) died. It uses the fact that carbon in Earth's biosphere maintains a known ratio between the isotopes 12C, 13C (irrelevant for carbon dating) and 14C. Its intake by living organisms (by photosynthesis, in the case of plants, or by consumption in the case of non-plants, accounting for known {{w|Fractionation of carbon isotopes in oxygenic photosynthesis|fractionation}} differences) is also relatively stable, until the organism dies and stops taking in carbon compounds. From that point on, its relative concentration in the dead organism can only decrease through radioactive decay. By measuring the relative amount of 14C left in the organism's remains, archaeologists can determine how long ago that organism last actively replenished its carbon, and thus how long ago it died.

Here, however, [[Ponytail]], in the role of a {{w|cosmology|cosmologist}}, takes a rather different perspective on using carbon for dating. She is interested only in the mere ''presence'' of carbon, which tells her that the skeleton being studied was formed after the first carbon in the universe was created in the first round of stars fusing elements, 13.6 billion years ago. This is not useful information for differentiating artifacts originating on {{w|Earth}}, which is itself less than ''5'' billion years old, since it would apply to all of them.

The title text looks like the kind of statement that would provide corroborative dating evidence for an archaeological site. The type and composition of tools can help to place a site, relative to others, on a {{w|Tool#History|developmental timeline}}. Here, however, they claim that the presence of stone tools dates the site as later than a non-existent age of helium tools. Tools made out of stone, usually dating from the {{w|Stone Age}}, are often solid and durable, making them great choices for heavy duty tasks, and well-preserved in the archaeological record. {{w|Helium}} is a gas and is difficult to shape into a solid mass for use as a tool.{{Citation needed}} It would also be near impossible to identify such tools if they had existed, since they would tend to disperse easily. Helium was produced in great quantities after the {{w|Big Bang}}, accounting for about ~25% of the mass of atoms produced by the early universe, so would have been available before stone was, but there were no people around at the time to fashion tools from it.

14C is generated in the atmosphere by interactions between nitrogen and cosmic rays, and it is radioactive with a half-life of approximately 5,730 years. It decays over time even as it is replenished, leaving its relative concentration in the environment a matter of the balance between its creation (by cosmic rays, which vary slightly over time, but in a way that can be enumerated) and decay (a constant proportion). Carbon dating is a useful method only so long as the remaining concentration of 14C can be measured accurately, which extends to approximately 9 or 10 half-lives (50,000 to 60,000 years) until the continued halving of the remaining isotope becomes statistically or physically difficult to accurately determine, as well as for lengths of time that are significantly ''less'' than this isotope's half-life. Other forms of {{w|radiometric dating}}, based on other elements and isotopes, are used for different lengths of time, as well as situations where such carbon-chemistry is not a reliable component of a sample, or may further validate the result in situations where their respective useful scenarios overlap. Even the ratios between abundances of stable isotopes can vary, providing historical information about things such as temperatures and atmospheric mixing, via {{w|isotope geochemistry}}, as well as in a wider form of {{w|radiometric dating}} for which the presence of stable decay products in a sample can be used to show the original concentrations of subsequently decayed atoms for even better cross-comparison of how much samples such as this will have aged.

The themes of the comic are similar to [[2723]], which imagines a periodic table published just after the Big Bang, when most elements did not yet exist.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[Ponytail, standing, is pointing at a blackboard containing a drawing of a skull and some bones/bone fragments, as well as a graph and some lines of text. She is speaking to Cueball and Megan, who are standing beside her.]
:Ponytail: The high carbon content of the skeleton indicates that the individual lived less than 13.6 billion years ago, after the first round of stellar nucleosynthesis.
:[Caption below the panel:]
:Cosmologist carbon dating

{{comic discussion}}<noinclude>

[[Category:Cosmology]]
[[Category:Biology]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]