2847: Dendrochronology

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These anomalies are known as Miyake events, named for the pioneering scientist who discovered them and was tragically devoured by a carnivorous tree.
Title text: These anomalies are known as Miyake events, named for the pioneering scientist who discovered them and was tragically devoured by a carnivorous tree.


Dendrochronology is a scientific method of using tree rings to tell the age of a tree and learn about historical climate from features found in each ring. It's based on the fact that trees add a new ring each year, so counting the rings will tell a tree's age in years. Additionally, climate and ecology affect the size and composition of each year's ring, so scientists can use rings to estimate what conditions were like each year. They can cross-compare tree-ring samples from overlapping date ranges, of comparable trees grown and felled at different times, to build up and confirm a useful ring history well beyond that of a single tree.

In some cases, tree rings contain remnants of specific events, such as forest fires, large volcano eruptions, atomic tests or droughts. Extremely disparate years can often be seen represented by a clear visual change in the usual subtle variation of ring-growth. The comic posits that, in 1635, trees somehow became carnivorous. The ring for that year contains indications of the bones of the creatures that they ate. This was just a temporary condition, since the rings after this have no bones, but clearly was a coordinated event among different trees to have caused this to be a comparable marker. Events such as this may have reoccurred at other times, just not again/before within the lifetime of the particular tree illustrated.

The title text says that anomalous years like this are called 'Miyake events', after a scientist named Miyake who discovered them (and was subsequently eaten by the trees, similar to the origin of Thagomizer). In actual fact, a Miyake event is a period when a larger-than-normal quantity of certain isotopes are created by cosmic rays, possibly due to extreme solar flares. Evidence of these events can often be found in ancient tree rings, as physicist Fusa Miyake discovered when investigating tree rings from years 774-775. However, she wasn't then devoured by the trees – certainly not in 1635, which is centuries prior to her 2012-13 publications.

A surprising number of things can be actually found within the 'flesh' of trees, though mostly inorganic items (e.g., metal tools) that are placed and abandoned there long enough for the tree to expand its bark and woody trunk around them. Skeletal remains are more often found in the roots of fallen trees. They are mostly[actual citation needed] from bodies that were there before the tree started to germinate, or perhaps even were buried and then a tree deliberately planted to either mark or obscure the burial site. It is even possible that the young tree significantly benefits from nutrients derived from the presence of the cadaver, as certain actual carnivorous plants have evolved to do, allowing it to thrive more than other saplings, but in this case it would not be through the plant itself pursuing a 'deliberately' carnivorous behaviour.


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[A round cross section of a tree in beige, with a brown bark around the outside and approximately 35 narrow rings, along with one very wide ring that contains various white bones, including limb bones, vertebrae, and jaw bones.]
[Caption below the panel:]
Dendrochronologists can date wood samples by identifying growth ring anomalies that correspond to specific events. For example, it's often possible to spot the horrible summer of 1635 when trees turned carnivorous.

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Hello wonderful person. IYKYK

Is the set of bones supposed to signify something? Human perhaps? I see vertebrae. 13:27, 28 October 2023 (UTC)

The bones depicted appear to represent a subset of "generalized vertebrate animal", including arm, leg, and jaw bones in addition to the vertebrae. Humans are cited as prey species, but the bones in this specimen are far too small to be human. If a typical tree ring is 2 mm wide, the 1635 CE ring would have to be 40 mm wide to accommodate a 20 mm diameter human femur with free space, as shown. The ring is ca. 12 mm wide. This tree ate smaller vertebrates. Of course, different tree species likely had different prey ranges, as with carnivorous animals. 16:15, 28 October 2023 (UTC)
Yes, that's what he means by "carnivorous", he's claiming that one year this tree was eating humans, those bones are the remains of those humans. :) NiceGuy1 (talk) 06:01, 29 October 2023 (UTC)
"Carnivorous" doesn't necessarily mean "man-eater". It's eating creatures (and generally you'd go for "insectivorous" for certain eater-of-invertibrate diets, but it'll probably cover consuming anything in the Animal Kingdom, fish, fowl, etc). He actually only claims one human was eaten (the eponymous researcher of the phenomenon), even if it was possible that others also got fatally surprised by it. But it could be any arboreal creature (and maybe some unwise unarboreal but tree-adjacent ones). 18:05, 29 October 2023 (UTC)
"Carnivore" can indeed apply to creatures that aren't herbivores (animal vs plant consumption), although a common connotation is "a consumer of vertebrate animals, especially mammals, captured live." Subsets exist, for instance piscivores (fish eaters) and insectivores. The caption's "horrible summer of 1635" implies widespread predation of trees on humans, even if only one such human is (facetiously) named, and the specimen shown is too small (or the wrong tree species) to attack H. sapiens. The proximity of the date of publication of this comic to 31 October is perhaps not to be neglected. 04:34, 30 October 2023 (UTC)
True, carnivorous doesn't MEAN humans, just means "meat-eater", but that seems to be the implication here. :) The fact that he calls it "horrible" means he was talking about humans (people wouldn't be THAT concerned over animals being eaten, animals eat each other all the time). Obviously if this were to happen, wildlife would certainly be included among the victims, they roam the woods more, LOL! But the tone of "There was that ONE horrible summer..." (just picturing a faraway haunted look in their eyes), yeah, he's referring to humans. :) NiceGuy1 (talk) 06:37, 4 November 2023 (UTC)
Nevertheless, the sample of bones there cannot be IDed as human. The skull (extrapolating from the jawbone) is not, and perhaps some positive scale inference can be made, but even that enlarged ring doesn't seem right for the long-bones (if that's what they are) or vertebrae being human. The question being if "seeing vertebrae" meant human, and yet the direct answer depended only upon the interpreted use of that word, thus a non-sequitur and not actually related. Yes, there were man-eating-trees (or at least a tree eating one man/woman/child who was both insightful and yet blind to xanger), but probably not directly illustrated. 12:46, 4 November 2023 (UTC)
The jawbone DOES appear to be human, actually. :) He drew it a shade long, but it does have the "layout" of a human jawbone. I estimate that Randall actually intended them ALL to be human bones and didn't account for the fact that a carnivorous tree would logically also eat wild animals. :) I think he just roughly indicated a very large tree where all of these bones would be human-sized, I don't think he bothered trying to match scale. NiceGuy1 (talk) 05:46, 19 November 2023 (UTC)

So this tree was cut down in late 1642? 13:37, 28 October 2023 (UTC)

Its year of death was indeed 1642 CE per dendrochronology. As for being cut down ... given the dense layer of calcium phosphate in the sapwood, and the saws available in the mid-1600s, the question "how?" is nontrivial. 16:15, 28 October 2023 (UTC)
Wouldn't the bark make it 1643? Isn't a ring a complete year, the bark is the current year's ring forming? NiceGuy1 (talk) 06:05, 29 October 2023 (UTC)
The bark is on the other side of the vascular cambium from the xylem tissue, so it isn't part of a tree ring and doesn't count as a year, as I understand the matter. However, the drawing does permit the interpretation that a ring is forming under the bark. Since the bulk of a tree ring normally forms at the beginning of a growing season, this would indicate that the tree died in the first couple of months of the local growing season in 1643 CE. 08:09, 29 October 2023 (UTC)

So is the year 1635 a reference to some real event, or just totally random? 17:57, 28 October 2023 (UTC)

If it was totally random it would have been 4AD! 18:23, 28 October 2023 (UTC)
at first I thought maybe the Carrington Event (similar but smaller EM storm as Miyake events), but that was 1859. The only vaguely related thing I saw for 1635 was the first recorded US hurricane... you might say I'm Stumped (and if that's the meta joke here, insert Capt Kirk "Khan!" clip here, with the subtitle "Monroe!") - 19:41, 28 October 2023 (UTC)

Actually, the carnivorous trees aren't true trees. They are part of the same species as broccoli and kale. 22:37, 29 October 2023 (UTC)

Sorry, that hypothesis has been falsified. Despite Randall's best efforts. (Sly of you.) 04:45, 30 October 2023 (UTC)