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100

Plants already communicate, we simply ignore or are just now starting to discover most of the mechanisms they use. An African tree has been found capable of communicating with its neighbors to warn them about excessive consumption from antelopes, so that they can secrete more tannine. (paper cited below) Tomatoes communicate using roots: plants growing ...


100

Underneath the outer cork-like layer of bark, the trees have a second foam-like layer. The cells of this layer are filled with a volatile liquid (in the chemistry sense - meaning it evaporates easily) which the tree uses to help boost water and nutrients up to the crown. Unfortunately for your would-be loggers, this liquid, once it evaporates into a gas, ...


72

First off let me say yuck!, that is a series of Google searches I can never take back. But as to your question, apparently plants often germinate inside the human body, specifically inside the lungs, as the warm moist environment is good for sprouting a seed. There are multiple reports of this happening with a variety of plants, this was widely covered ...


71

The tree was never supposed to be a tree, it was supposed to be a natural boost to the air quality and be a feature of the building. The architect had a great idea for a natural air circulation and freshening system. You plant this tree up the centre of the building, it acts as a visual feature through the middle of the tower up a central transparent air ...


68

We're boned. You described a virus that is... air, fresh, and saltwater borne destroys plants and their seeds in two days can survive in all terrestrial environments can go dormant, presumably in some sort of spore does not affect anything but plants has been in the wild for a few months Normally a virus which kills its host in just two days would burn ...


66

The most likely reason would be that they simply don't have anything that can cut them in your scenario. You say that the trees are highly valuable, so there's a high motivation to cut them down. This suggests that no matter how difficult it is, the reward is worth it. So, the only other possible reason to not be able to cut them down is going to be ...


63

It's more likely there could exist a plant which has a flying phase of its life-cycle. Does it really fly? It might be more appropriate to call it floating, since the energy required for what is more traditionally thought of as flying, would be too much for a plant. Blimp plants/animals have long been imagined in science fiction, called living gasbags. It'...


61

If you allow the third kingdom (after plants and animals), namely fungi (mushrooms and their many, many cousins), then yes. Fungi will take care of the oxygen surplus, using it up and releasing CO2 for the plants to breathe. For pollenation: There are plants that use the wind for this, and other plants reproduce through non-sexual reproduction - strawberry ...


55

Plants give off CO2 at night, when they start to respirate using the 'fuel' (glucose) synthesised by photosynthesis in the day. Check out the Calvin-Benson cycle


50

A plant could produce a diamond chemically by laying down carbon atoms in the right crystalline formation. Heat and pressure are for geological diamonds, they aren't relevant when you're dealing with atoms at a time. There is no reason for them to do this, evolution-wise, but since you're talking about genetic engineering that doesn't matter. Forming ...


47

13 square meters BIOS-3, a sealed, underground compound designed to mimic a spacecraft, managed to generate oxygen for humans using algae. Its specifics are outlined in an article by Salisbury et al.: A crew of up to three people 315 cubic meters of living space (14 m by 9 m by 2.5 m) 3 phytotrons, or algal cultivators, covering 63 square meters Originally,...


46

Plants existed before animals ever evolved, and if all animals were to disappear, plants would continue to exist a million years from now. Just mostly different species. Respiration. Plants produce both CO2 and O2. Without animals, there would be a higher concentration of O2. If you wanted, you could easily evolve plants that have internal processes that ...


45

I know this is a slightly short answer, but it applies to most European trees (not all I admit) at least: if you hammer a copper stake into the tree low down, close to the roots, it will poison the tree and it will die. This does take a few months, but it is possible. However in real life this only works on a living tree, cutting it down kills them, but in ...


45

You don't have to speculate very far at all; it's a widely accepted notion, since Prof. Suzanne W. Simard's 1997 research paper, "Reciprocal transfer of carbon isotopes between ectomycorrhizal Betula papyrifera and Pseudotsuga menziesii" that plants communicate using chemical secretions, primarily through their root systems. Her team proved this by ...


45

There are trees which are capable of killing large animals, in fact, only they don't eat them afterwards. But it's a start. Pisonia brunoniana is known as the birdcatcher tree for a reason. The seed pods of this tree are coated with a mucus which traps insects - even this alone could evolve into carnivory, but wait till you hear what happens next. These ...


44

There's a reason why "salting the earth" is an expression. Excessive salt will suck out the water in plants and kill them, leaving the skeletons behind. you will need to ensure the salt can't have washed away since. This salt could be suddenly supplied by a volcano by having the volcanic ash containing a large amount of salt. Otherwise some evil conquerers ...


42

A plant chasing humans would be unrealistic, but I think a plant generating a trap for human-sized animals could be possible in principle, given the right circumstances (maybe it evolved from one eating smaller animals, but those got extinct, and the trap size grew to capture ever larger animals). The most obvious way would IMHO be if the plant managed to ...


41

A multi-pronged strategy. First, simple chemical tests would be performed for heavy metals and strong acids/alkalis and to give a general profile of the plant or animal's chemical composition. Gas chromatography should throw-up a number of interesting results and help identify known poisons. This, whilst being careful to identify any specific part of the ...


40

Evolution and benefits It is easy to think of evolution as only being about benefits, but in order for something beneficial to be naturally selected it must first arise spontaneously. The fact that plants have not so far evolved bioluminescence does not indicate a lack of benefit. It simply means that they have not stumbled upon a way of doing so. Some ...


40

Humans have a built-in ability to learn languages. While this ability is greatest in young children, it never goes away. What you are looking for is called learning a language by immersion. It has been practiced in all times and in all places by very many (millions of) people, in most cases because they had to. Think of the countless language shifts which ...


38

Prototaxites! Fossil mushrooms are rarities. Mushrooms are the fungal equivalent of flowers - spongy, ephemeral, disposable bodies generated to serve a reproductive need. You could not use mushrooms for wood. The prototaxites were not mushrooms. They were large and substantial; up to 7 meters high. https://www.smithsonianmag.com/smart-news/long-...


36

Diseases or toxins Maybe the forest is a hazardous place due to various diseases thriving in local flora or fauna for example Malaria mosquitos. Bandits would not be immune, but well maybe they have little other choice than to soldier on. Or the trees are dangerous. Perhaps there's no problem if you leave the trees alone, but if you start chopping them ...


36

People get the wood. The trees are cut. They are just not cut down. There is no need to cut them down. Your forest is a pollard forest. https://en.wikipedia.org/wiki/Pollarding Pollarding, a pruning system involving the removal of the upper branches of a tree, promotes a dense head of foliage and branches. In ancient Rome, Propertius mentioned ...


35

Well, it all depends! :) There are tumbleweeds which grow, produce seeds, then die, break off and the whole plant moves by the wind, depositing its seeds in different ways, it's sort of like flying. Of course seeds fly all the time, dandelions and other similar flowers, Maples have their little helicopters. However, for plants to fly, first they need ...


34

Plants would be blue if their photosynthesis were based on phycocyanin instead of chlorophyll. Since there are organisms on earth that use this, it's not entirely implausible that it could be used also by higher plants in an alternate world. So what environmental effects could cause phycocyanin instead of chlorophyll to be the dominant photosynthesis ...


34

Take a look at this description of how DNA sequencing works, both today and 30 years ago. Basically, 30-odd years ago we did sequencing manually with a whole bunch of scientists (and/or interns) chugging through line after line of DNA molecules. It was an incredibly tedious process, which is why we've since passed it off to computers. However, while ...


33

If you want a carnivorous plant to eat large animal it needs a quick way to disable and kill them. The venus flytrap relies of it being structurally stronger than the insects, the pitcher plants just outright try to drown the insect to get it to stop escaping along with the slippery walls of the pitcher. So how could a plant quickly disable a large animal? ...


32

From the plant's point of view the herbivore is a predator. The only thing that matters as far as that goes is that more plants grow than the herbivores can eat, otherwise they will run out of food and die. You have the same problem in your case, with one additional problem: the cycle of energy. Basically, plants capture and use solar energy to grow. When ...


32

Reasons for plant coloration Plants would develop pigments that let them absorb the parts of the spectrum that are most valuable to them. Here are the absorption spectra for the two types of chlorphyll in plants: As you can see, plants absorb almost nothing in the green range, so green light is reflected; thus plants look green. Red algae, on the other ...


32

You need to have direct sunlight that can be dispersed to see a rainbow. If you have only already dispersed light, no rainbow can occur. If you have a permanently cloudy atmosphere (like it is the case on Venus), there never will be direct sunlight, and thus no rainbows. If you need a solid physical explanation for it rather than a handwaving "different ...


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