1749: Mushrooms

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Evolutionarily speaking, mushrooms are technically a type of ghost.
Title text: Evolutionarily speaking, mushrooms are technically a type of ghost.


Cueball is looking at a mushroom, contemplating how weird they are, when Megan adds another layer to their weirdness by supplying the trivia that evolutionarily, mushrooms (which are basidiomycete fungi) are closer to the animal kingdom than to plants on the tree of life. (Note that, technically, mushrooms themselves are only the fruiting bodies of the fungi. A mushroom is only part of a fungus, in the same way an apple is only part of a tree. The majority of the fungus grows beneath the soil, in a part of the fungus called the mycelium, which is composed of root-like structures called hyphae.)

Both animals and fungi are part of the opisthokont group of eukaryotic organisms, while plants are in the archaeplastida group of eukaryotic organisms with the green and red algae. This surprises Cueball, as he, like many people, is likely to think of mushrooms as plants, as they are "grown" just like other crops. Even scientists, before the 1960s, considered fungi to be 'plants'; it took DNA-based studies in the 1990s and 2000s to 'seal the deal' and place the fungi with the animals, and not the plants. But fungi do not perform photosynthesis, and therefore do not need sunlight to grow. Instead, they get their energy from other living matter, either live (parasitic mushrooms) or dead (e.g. manure; saprobic mushrooms). Edible mushrooms like Agaricus bisporus (or white mushroom) are saprobes, farmed in caves. The body plans of fungi are also utterly unlike those of plants. There are a few plants that don't do photosynthesis, such as the parasitic flowering plant Monotropa uniflora. But these plants otherwise look like, and are built like, plants, and don't look or grow at all like fungi. Ironically, many plants, both photosynthetic and nonphotosynthetic, depend on root-associated (mycorrhizal) fungi for their survival and growth.

Megan then walks away, and Cueball, after pondering the mushroom a while further, gets up and walks away too. But as soon as Cueball has his back turned the mushroom growls after him. Cueball spins around to look back at the now again silent mushroom. This is a bit of absurdist humor; while mushrooms are technically more animal-like than plant-like, they are still so far removed from animals they wouldn't have any of the body parts needed to growl. For that matter, most animals lack the parts needed to growl. Cueball's shock and astonishment is quite justified, and maybe it was just his imagination running wild after Megan's trivia. The reader is left to wonder what Cueball's next move will be - especially, those readers who have ever felt, or indulged, the urge to stomp mushrooms.

Another interpretation of the mushroom's growling is that mushrooms might be "fake" animals disguising as plants. The mushroom seems to be a plant, and acts very plantlike until Cueball looks away. The mushroom might have growled because it was planning on killing Cueball in a sort of "kill the witnesses" action. This comic might be hinting that mushrooms are evil and plotting the downfall of humanity under the disguise of "harmless" plants.

The title text takes this further, by stating that mushrooms are technically a type of ghost. Maybe because they arise from decaying remains. The title text may also refer to 1240: Quantum Mechanics or 1475: Technically, suggesting caution when dealing with a statement preceded by "technically." It may also refer to the other name of Monotropa uniflora, "ghost plant" which hosts are certain fungi.

The title text might also refer to the behavior of ghosts (called Boos) in the Super Mario series, in that they only act or move when the player is facing away, as does the growling mushroom.


[Cueball is squatting in front of a group of four mushrooms (two tiny, one small and one large), touching the top of the nearest and largest mushroom with a finger. This mushroom has several small dots, which becomes more visible in later panels. The other three mushrooms do not appear to have these dots. Megan is standing behind him looking on.]
Cueball: Mushrooms are so weird.
Megan: You know, evolutionarily, they're closer to being animals than to plants.
[Megan starts walking away as Cueball now leans on the ground with the hand he touched the mushroom with. Only the large mushroom is visible in this and the rest of the panels.]
Cueball: ...Really?
Megan: Yup!
[In a frame-less panel Cueball still squats in front of the mushroom, now resting his hand on his knees.]
[Cueball stands up looking down at the mushroom.]
[Cueball is walking away as the mushroom makes a sound indicated with several small lines emanating from the top of the mushroom along with a regular speech line.]
Mushroom: Grrrr
[Cueball snaps around to look at the mushroom again, standing in a prepared state arms slightly out and legs spread out as well.]

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Meaning of the title text?

The way I'm reading this comic, there are several possible meanings to the title text. One definition of "ghost" is "a faint trace of something" - it's possible that mushrooms are a faint trace of whatever other species bridged the gap between plants and animals.

Alternately, it could just be Randall's way of saying not to trust any sentence beginning with the phrase "Evolutionarily speaking" (see comics 1240, 1475). 13:55, 21 October 2016 (UTC)

C-C-C-Combo Breaker! PeanutVendor (talk) 14:08, 21 October 2016 (UTC)

Disagree with stated meaning. Yes, fungi consume dead matter but that would relate them to zombies not ghosts. Suggest that its a reference to asexual reproduction in fungi, that new fungi are born from the broken bodies of its parents. Kev (talk) 17:05, 21 October 2016 (UTC)

I think it is mostly just poking fun at the "X is actually a kind of Y" facts. The specific choice of "ghost" may be completely random, or may have some internal logic, but it's not the main point even if it does. I remember reading a similar joke in a Discworld novel (The Last Continent I believe), where it is said that banana is not a fruit, but a species of fish. Randall references DW from time to time, so it is likely he has read this joke and consciously or unconsciously copied it. Jaalenja (talk) 12:34, 24 October 2016 (UTC)

Some mushrooms are more or less ghost-shaped. Omphalotus nidiformis is a glow-in-the-dark mushroom that is also called ghost fungus (https://en.wikipedia.org/wiki/Omphalotus_nidiformis). 12:49, 24 October 2016 (UTC)

Since this cartoon came out in October, ghost may also be a seasonal choice, related to fall and Halloween. Mushrooms are sometimes associated with fall and graveyards. Dead Man's Fingers is a kind of mushroom. 00:37, 1 November 2016 (UTC)

I took the reference to evolution and Ghosts as a reference to Pokemon. In this case though a mushroom looks like a grass type (plant) it is actually closer to a ghost type. Davem33 (talk) 01:16, 14 December 2016 (UTC)


Not sure I agree with the explanation of the growl. In the first frame cueball insults the mushroom as Megan explains they are more like animals; the casual/layperson implication there is that, while not necessarily sentient, they are more able to respond to surrounding stimuli (like being aware of being called weird.) So the punchline in the penultimate frame has this not-vegetable more-like-animal mushroom "animate" ... growl IronyChef (talk) 15:03, 21 October 2016 (UTC)

You can also look at the growl from a much simpler viewpoint, especially if you have a pet at home: It could be that the mushroom (which you have just found out is closer to an animal than a plant), enjoyed being touched by cueball - almost like a dog likes to be petted. When cueball stopped and walked away, the mushroom got upset and growled at him, much like a dog would get upset if it was enjoying the petting and you stopped! -edit: oops forgot to sign! Bon (talk) 08:17, 24 October 2016 (UTC)

(wild guess) The growl could also be related to predation. As is stated in the explanation, mushrooms can get their sustenance from living matter. Maybe cueball turning his back causes the mushroom to prepare to pounce on him from behind. 14:16, 24 October 2016 (UTC)

Differences mushroom/plants

Just for a quick overview:

  • cell walls in mushrooms consist of chitin (like the exoskeletons of insects) and polysaccharids. Plants have cells walls made from cellulose, animals have cell walls made of protein.
  • mushrooms are heterotrophic (they need to take up chemical energy from outside of the body) like animals; while plants use sunlight. Though, some fungi have turned to sunlight or gamma rays (https://en.wikipedia.org/wiki/Radiotrophic_fungus).
  • each fungal cell is simple in structure and function, unlike plants which have much more specialized "organs" (leaves, flowers, roots)

-- 16:16, 21 October 2016 (UTC)

Animals do not have cell walls. All cells (including Plant, fungi and animals) have cell membranes made of lipids with embedded proteins. As above, plants and fungi have cell walls in addition to a cell membrane. Some other things such as bacteria (which are not animals) also have cell walls made of various substances.-- 16:55, 21 October 2016 (UTC)

Also note plants are eukaryotic so it's not fair to say "(eukaryotic organisms do not use photosynthesis)". The definition of a eukaryote is the presence of a nucleus not anything to do with heterotrophs (eat others for food) vs. autotrophs (produce their own food). 21:35, 21 October 2016 (UTC)

Actually some plants can grow without light, which is parasitic and can't photosythesize at all. Also Rhubarb is grown in the dark (using prestored energy) https://en.wikipedia.org/wiki/Rhubarb_Triangle Halfhat (talk) 22:04, 21 October 2016 (UTC)

Thinking on a tangent, is Cueball on shrooms? -- Vnagpal (talk) (please sign your comments with ~~~~)

Thinking on a cotangent, is Cueball under shrooms? -- int (talk) (please sign your comments with ~~~~)