> Although the mechanism has yet to be explained by science, many believe there is some kind of natural “alarm clock” in the plant’s cells causing the behavior.
That is amazing. I'm having a hard time imagining how that could even be possible, for DNA to have an "absolute" sense of time. Some kind of day/night/time of year "counting" mechanism?
Counters in biology are also a thing, for example Hayflick limit [2] which is a number of times a single cell can divide before it dies (partially explained by telomere shortening due to particularities of replication of the lagging DNA strand 3). What is interesting here is that plants from the same clone grown in different climates likely grow at different rates so the counter must be decoupled from cell division. Perhaps accumulation of some metabolite that adds up every season triggers it at some threshold?
[1] https://en.wikipedia.org/wiki/Periodical_cicadas [2] https://en.wikipedia.org/wiki/Hayflick_limit [3] https://en.wikipedia.org/wiki/Telomere#Shortening
+-------+---+---+---+---+
| Cycle | A | B | C | D |
+-------+---+---+---+---+
| 1 | 1 | 0 | 0 | 0 |
+-------+---+---+---+---+
| 2 | 0 | 1 | 0 | 0 |
+-------+---+---+---+---+
| 3 | 1 | 0 | 1 | 0 |
+-------+---+---+---+---+
| 4 | 1 | 1 | 1 | 0 |
+-------+---+---+---+---+
| 5 | 0 | 0 | 0 | 1 |
+-------+---+---+---+---+
And then if gene D triggers flowering: Tada! you would get one flowering every 5 cycles. In practice things are never this simple. The gene expression rules are not that straightforward, the genes do not all express in the same cycles, you need some mechanism to keep things in sync between cells and plants etc. But the simplified model shows how powerful oscillator genes with expression switches can be.
"According to their ‘delta T’ (ΔT) model, the likelihood of masts by several species, including beech and tussocks, is positively correlated with the difference between average summer temperatures in successive years: a high positive value of ΔT (i.e. last summer warmer than the preceding summer) corresponds to a high likelihood of a mast in the coming year."
I'd always imagined that these types of events involved pheromone-type signaling, but this is kind of a cool way to do distributed consensus based on external signaling.
Here's my recollection:
Essentially a single bacteria can't make you sick, and if it tried, it's so small that it would have no effect. Triggering a collective effect becomes critical for them to cause disease. Disrupting quorum sensing might be a way to fight otherwise resistant bacteria.
In principle Yes but is an extreme example. Is possible also that the plant just will die before if roots are damaged in the process and their reserves are depleted.
There was/were some species of bamboo used by craftsman that bloomed and then failed to reproduce due to weather changes. You've been working with a species of bamboo for five generations and it's just completely gone in under a year.
I thought it's a well-studied fact that humans settle on a 30 hours sleep-wake cycle in constant light conditions?
The Circadian Clock is essential for coordinating metabolism, growth, and reproduction, vernalization, etc. Most plants can be considered either short-day or long-day flowering, where highly-sensitive response to the delta in day-length is tracked to coordinate flowering. Nearly all plants anticipate events like sun-rise and sun-set with precision to coordinate (expensive!) photosynthetic expression, open/close stomata, alter xylem and phloem, etc.
Applying this to longer time-scales should not be terribly surprising for such sophisticated time-keepers.
Here's some information about in-vitro induction of flowering, induced with the sorts of chemicals you might expect (e.g. cytokinin promoting, auxin repressing):
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5603696/
As for the particular regulatory network that accomplishes this, it's very difficult to study an event that occurs so seldom. Even annual breeding cycles can make detailed genetic investigations take decades.
What we can infer from homology is that there's likely some kind of feedback and balance of hormones that 'count' the time. There is nothing "in the DNA" that tracks time, but the genes that DNA encodes can provide this clock function.
> For example, devastating consequences occur when the Melocanna bambusoides population flowers and fruits once every 30–35 years[6] around the Bay of Bengal. The death of the bamboo plants following their fruiting means the local people lose their building material, and the large increase in bamboo fruit leads to a rapid increase in rodent populations. As the number of rodents increases, they consume all available food, including grain fields and stored food, sometimes leading to famine.[7] These rats can also carry dangerous diseases, such as typhus, typhoid, and bubonic plague, which can reach epidemic proportions as the rodents increase in number.
https://en.wikipedia.org/wiki/Mautam
Causes famine. The Northeastern Indian states of Mizoram and Manipur are somewhat near the Bay of Bengal.
This would fit very well with the notion that starting a new era also means a new start. (It might make people a little eager to overreport I suspect.)
(Before Meiji era, Japanese emperors used to routinely proclaim new eras when some notable event happened or they just felt change was needed. Common reasons are big earthquakes and other natural desasters, for example, but there also eras that were started over the sighting of a white or red bird or the find of a gold mining spot (it actually turned out not to be). (The mean era length is something like 5 years.))
But my clones are taken from a variety that flowered in the 90's, IIRC, so there's some confidence they won't all flower (and immediately die) for another ~70 years.
The variety they're talking about here is a mild running type (most runners are very rampant, and not recommended unless you've got containment systems in place).
Thailand famously had a big flowering event in the late 1980's that killed off vast tracts of plantations.
I may be wrong. The previous owner of my neighbor's house had a bamboo garden... the current owner was not aware of how to maintain it. The previous owner of my house had a rose garden. I am not a particularly clever gardener, and having grown up in Minnesota, was not familiar with the habits of bamboo. The bamboo ran under the fence, and attacked the roses in our yard before I noticed it. The bamboo identified rose bush root clumps, attacked, surrounded, and choked them.
So in the aftermath, I ripped out dead roses and built a play structure for my offspring, my neighbor ripped out the bamboo jungle and created a nice patio, so we both netted out OK. Our research led us to determine that a trenched solid barrier should have been put in place originally, but we weren't going to test the theory.
As noted by dbcurtis, you need to have a physical barrier -- either metal (but that'll eventually corrode) or some very thick rubber (ditto), or concrete - to about 60cm depth, depending on variety. Alternatively they are typically stopped by roads and permanently running creek beds.
My clumpers (Bambusa oldhamii, B.multiplex, B. ventricosa, and B. gracilis) vary in height, but after 15 years the largest is, albeit a very dense, 1.5m diameter clump.
> Some cicada species have much longer life cycles, such as the North American genus, Magicicada, which has a number of distinct "broods" that go through either a 17-year or, in some parts of the region, a 13-year life cycle. The long life cycles may have developed as a response to predators, such as the cicada killer wasp and praying mantis. A specialist predator with a shorter life cycle of at least two years could not reliably prey upon the cicadas.
There's also an evolutionary theory behind why these are prime numbers: https://www.newyorker.com/tech/annals-of-technology/the-cica...
It's wonderful to learn of something so 'purely' interesting, and (now I've dived a little down the rabbit hole) shared amongst other species like Cicada.
What?
I thought bamboo is a fast growing thing, and it's easy to grow bamboo. Just stick it into the soil in the right conditions and it'll sprout roots and grow. (It can even be grown from seeds.)
As the article mentions, some types of bamboo will flower only once every 100 odd years. When they do, they pollenate each-other and grow fruits and die.
In some parts of the world rats will feasts on these fruits, and rodent populations will explode, contributing to the "Bad Omen".
> Just stick it into the soil in the right conditions
When all the bamboo decides to flower and die at the same time, what exactly are you planning to stick in the ground?
Presumably, the seeds from the fruits from the last generation. Though they would certainly take a bit of time.
The seeds from the flowers?
Hm, maybe keep saplings inside when you see the flowers growing?
Or try to cut off the flowers to prevent the die-off?
Okay, maybe that's a lot of work, and no one prepared for that?
One theory I was researching was the grand solar minimum.
In the 21 century finding some glass jars or metallic recipients with a solid cover lid shouldn't be a great problem. If you can find a beer or a cocacola in your village you have yet a rat-proof recipient for safely storing seeds. Rodents are edible also if not other food is available
Is also interesting to notice that this bamboo ecology fact, seen as a symbol of bad luck, gave us an unexpected and priceless gift: chicken eggs. Domestic hens are able to lay 12 months a year because red jungle fowl and bamboo forests are linked and evolved to get advantage of years of bamboo flowering
Unless you are highly adept at making rat jerky you are going to be in trouble when winter comes.
Why would the response of cats, dogs, and foxes be different now than in the past?
Why don't link the complete article instead of the japan-forward one?
However, your confusion is understandable.
Nathaniel Kleitman spent a month in a cave in 1938 studying sleep/wake cycles, and found that he could maintain a 28 hour cycle. He did this deliberately, however, and this does not reflect the circadian rhythm. Rather, this wake/sleep cycle depends on C (the circadian rhythm) and S, homeostatic effects that reflect the previous period of wakefullness. It's also entirely possible to sleep at any point in the circadian rhythm (as anyone who has napped will know), so the circadian rhythm can simply decouple in extreme wake/sleep cycles (e.g. 20h or 28h).
http://www.chronobiology.ch/wp-content/uploads/publications/...
Also, even with the circadian rhythm not being preciesly 24 hours, it's still 24 hours with entertainment. That's the standard physiological condition; it really is a 24-hour cycle. Free-running is like removing a component of the clock, seeing that it doesn't keep 24-hour time, and calling it broken. That's not the case; entrainment is part of the process and how the body keeps coordinated with its environment.
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If I have a cell with 5 "beans" (hypothetical counting organelle) in it. And the cell will die if it does not have at least one bean. These beans stack on top of each other like Legos, and "float" inside the cell so that the top bean is at the surface of the cell, exposed to the weather. Every winter the exposed bean dies, so that each year there is one less bean - and the next highest bean is now "floating" at the top. After 5 years there will be no beans left and the cell will die.
Now try to do that by counting up. How does it work?
OTOH, the author seems distinctly... less scientifically inclined than the bulk of commenters here. They may have simply meant "of the same genus".
But they’re not the same:
https://zippyfacts.com/what-is-the-difference-between-katydi...