A fruit that electrically shocks you

Question

I want my world to contain a fruit that electrically shocks you to the point where it's painful, whenever you bite into it. Now, there are many organisms in nature that produce sensations similar to electricity (jellyfish, electric daisy, etc.) but I want my fruit to actually shock you. What would have to happen for this to be possible, and what might be different in a world where such a fruit exists? Some ideas:

• The fruit could have evolved electrocution as a defense mechanism, similar to how cacti are prickly or peppers are spicy.
• Could this fruit be used culinarily? Maybe you can make a dish with this fruit in small quantities to have a tingly effect.
• If this fruit is essentially a natural battery, you could produce fires much easier than by rubbing sticks together. How might this impact society? Could this fruit start fires spontaneously?
• Would this fruit have lead to earlier development of electricity and related technologies?

Answer 1

How it would produce electricity? Most likely, the same way electrical eels do, I suppose - a mesh of long cells, that get electric potential due to work of ion channels. They would be activated by some activator being released in fruit when it is damaged, the same way damage of the endothelium causes coagulation.

About evolution of such plant - it could start from plant signalling to insects via electric field(many insects react to them) and later signalling cells would change the purpose the same way nerves of electrical eel became weapon(it kills its victims with thought :) ). Another interesting way of using electricity - electrolysis of hydrogen for flying seeds(though hydrogen can be more efficiently generated via usual organic reactions).

// fruit is simply a means of attracting animals to disperse those seeds. having vectors chased off by electric shocks is not a positive evolutionary trait.

One animal may eat the plum, swallows the seed, and excrete it far away later, surrounded in fertilizer. Another one may eat the juicy part and spit out the seed nearby. Obviously, plant would prefer the first one. So if fruit is swallowed and slowly digested it would not produce electric shock, if it is eaten by parts, it would shock the animal.

Answer 2

Building off of ash, which is a nice idea, the charge is what draws the 'animals' to the fruit. They have a corresponding organ to harvest that energy. They use the charge, just as we use the sugar in our fruits.

Answer 3

"Electrocution" means "electrifying something until it dies".

So, why would a plant do this? Because it's a carnivorous plant that feeds on them. The fruit are just a lure. As for how, well, I think you hit on it when you mentioned the electrical eel.

Answer 4

Fruit is designed to attract not repel predation, as such an electric charge is generally counterproductive.

There may however be a reasonable explanation for an electric "fruit" of sorts; consider that the "fruit" is not a sweet fruit that we would tend to think of when we hear the word but rather a body containing seeds like a pine cone that is sealed against the elements until such time as the weather is right to disperse the seeds and have them germinate. Such cones often rely on fire in the modern world but an electric charge could serve a similar purpose or could in fact be an ignition source for a fire dependent species. Cones could build up a friction charge from the wind and/or the rubbing of cones against each other, you would not want to touch a charged cone. This is not a "fruit" that would not be used for food nor, at least in my opinion, would another example of biological electricity advance the development of the science any. I in fact would expect that this would have little overall impact on the world we know since such trees would live within existing burn dependent forest ecosystems.

Answer 5

Here is how the fruit could do it:

A charge is gradually accumulated on the inside (via ion channels in the usual method). An insulating layer of avocado-like fat wraps this inner pulp. The thin outside layer accumulates the opposite charge.

On biting into this fruit, the biting apparatus of the eater completes the circuit. The outer and inner layers equilibrate, with charge coursing along the mandible or mouthparts of the fruigvore.

One fruit could deliver one shock. That might be enough to kill an insect or small animal. After the frugivore ceases its effort (and falls off). the fruit might be able to heal and regenerate charge, just as a fruit which is pecked or otherwise cut while still on the tree can sometimes repair the damage given time.

Fruits dissuade frugivores all the time. Especially to be dissuaded are insect frugivores, who spoil the fruit and are too small to disperse seeds. If the fruit is eaten before the seed is ready then the whole seed dispersal scheme is kaput. Unripe fruits are bitter tasting to us or unpalatably sour, and contain proteases and other enzymes intended to disrupt the digestion of fruigvores intended to eat them before they are ripe. These substances are why one must cook green tomatoes. Fruits also want to dissuade the wrong types of frugivores - hot peppers being a prime example. Peppers do want to be eaten, but by birds, not mice. Mice will chew up the seeds but birds will pass them.

A fruit like this will maintain a charge only while on the tree. Just as a ripe fruit will turn off proteases and other antifrugivore mechanisms, when it wants to be eaten this electric fruit will cease to maintain its charge. Once off the plant, the energy source (from the leaves) used to maintain the charge differential is gone, and the charge difference will slowly wane. An electric fruit might use a shock like this to make sure it is eaten only after falling on the ground (by something like a coati who will disperse the seeds).

Answer 6

I'm seeing a lot of people saying that the point of a fruit is to attract animals to eat it... but, all the plant really needs is for at least one animal to be able to eat it. Take a look at the manchineel tree. It's one of the deadliest plants alive, with sap that can damage the paint on cars. Standing under it during a rain will cause your skin to blister, and burning the tree causes smoke that can burn your eyes... so, needless to say, ingesting its apples is a pretty bad idea.

Unless you're a black-spined iguana, which eats the apples and lives in the boughs.

It's a tenuous relationship, of course--if anything happens to the iguana, the tree is done for--but as long as it holds, the machineel tree is nearly invincible to attack from herbivores and parasites, and the iguana has a reliable food source with no competition and a safe place to live.

All you need is at least one animal with a mouth that conducts electricity poorly (or perhaps is smart enough to coat its mouth in something that is first), and voila, you've got your seed dispersal!

Answer 7

It wouldn't be an edible fruit, so it would use another form of seed dispersal. I am thinking a fruit that when it pops either because it matured or because something bit it shoots a multitude of small seeds at significant force. The seeds will when be carried by the wind. So I am guessing the normal trigger would be wind making the plant and the fruit sway.

How is this related to electricity?

Triboelectric effect creates voltage on separating surfaces. When the seeds are shot from the fruit they are obviously separating from it. If the connecting surfaces of the seeds and the fruit are in the opposite ends of the triboelectric series, both will acquire electric charge. On the fruit this would likely be irrelevant, but on the seeds the acquired charge would force the seeds apart from each other and spread the long fibers on their surface for maximal surface area. Both of which the plant wants.

I doubt this is exactly what you want, but eating a fruit like this would hurt and if the seeds have high ratio of surface area to mass, as they reasonably would, much of the pain would be from electric shock inside your moist and sensitive mouth.

Answer 8

You could easily have a scenario where the plant and some animal evolved together such that only this particular animal can safely consume the fruit. This facilitates dispersal of the seeds by a specific animal. The term is coevolution, and is fairly common in nature. In terms of a mechanism by which the electricity is generated, you could look to something like an electric eel, but I would consider instead lemon batteries for inspiration, where there's a chemical reaction between the juice of the fruit and electrodes. In your case, you could have some compound in the juice of your fruit that reacts with something commonly found in mouths of most species species. Perhaps a compound in saliva. Then, the animal that coevolved with the plant can have something different about it's saliva that inhibits the reaction, keeping it from getting shocked.

In terms of culinary uses, the intensity of the shock can be based on how much you dilute the juice you extract from the fruit. Dilute the juice enough, you just get a tingly sensation.

Answer 9

Re: the first part of Ash's answer (that I can't reply to) "Fruit is designed to attract not repel predation, as such an electric charge is generally counterproductive."

Capsaicin-containing fruits are an adaptation that repels mammals, who feel its effects and are less capable of spreading seeds after consumption, but not birds, who don't feel its effects and are more capable of properly spreading the seeds (wikipedia). If your world also features a species or taxon that is both better adapted to spreading your fruit's seeds and also somehow less vulnerable to being electrocuted while eating it, that would make evolutionary sense.

Answer 10

Many have pointed out that evolving electrocution powers on a fruit is counterproductive. So instead, what if...

The delicious but dangerous growth isn't a fruit

From its formation, this world has had terrible weather conditions. Sunlight is very limited in large parts of the world, and as such, the few lifeforms that have managed to evolve have done so by inventing methods for dealing with the lack of sunlight. Some did so by storing energy gained from the sun, perhaps by raising load-bearing branches on the uncommon clear day and lowering them to release that energy for survival the rest of the time, or by storing the energy mechanically or chemically.

This organism's solution was different.

Some plants are rich in zinc, and some plants are rich in copper. These are provided by the soil, which is in turn fertilized by dead organic matter. Your plant in question gathers both and applies them to an electrolyte-rich growth, just like a lemon battery.

This electrolyte-rich growth differs from a fruit in that it does not contain seeds. The growth is divided into chambers by organically-produced wax, which serves as an insulator and allows the chambers to be combined in series to produce a greater voltage. Biting into the growth provides a conductive connection between two chambers at differing potentials, resulting in electric current passing through the victim's body. Probably not enough to be fatal to any but the weakest of species, but likely enough to cause noticeable discomfort.

Answer 11

I can think of why the tree would do this, consider the chili pepper, the capsasin discourages large mammals that can digest their seeds so only birds (who are not affected) will eat them and spread their seeds. Now imagine your tree produces a strong charge in its fruit, birds would be unaffected but and large animal standing on the ground that tried to eat the fruit would get a shock because it completes a circuit with the ground. Now we have a reason your plant has such weird fruit it wants birds to eat it but not large animals becasue they can break down their seeds and birds can't.

As for how it does this this is not too hard cell membranes can make good capacitors, your plant just needs to stack an incredible amount of cell membranes together and build up a charge potential across them. Also consider that teeth are very electrosensitive (it has to do with how teeth first evolved), so this will work doubly well on most mammals, it may not even need that strong of a charge.

this also means that once the fruit has discharged it will take time to build up a charge again, so a clever human could figure out how to harvest them safely.

Answer 12

With some citrus fruits, such as a lemon, one can build a battery by inserting metal strips. The citric acid in the lemon causes corrosion of the metals, generating an electric current.

It is possible that a plant could extract the appropriate minerals from the soil, and transport them to the fruit, where they could be contained in some form of neutral fluid, until some creature bites into the fruit, bringing the acid into contact with the minerals, and electricity is generated.

With numerous containers of minerals, the fruit should be capable of producing several charges for multiple bites. It wouldn't take a lot of electricity to do the job - most animals have sensitive mouths, where even a mild electric charge will be extremely unpleasant.

Answer 13

It's not just the fruit itself, it's also the seed!

As the fruit decays, juice vesicles (like those in a citrus fruit) gradually release chemicals that produce a very mild chemo-electric current which triggers and supports the germination of the seed. When the fruit first falls, the impact with the ground releases a larger jolt needed to penetrate the somewhat-insulated seed coat. When the seed receives this jolt, not only does it start germinating, but it also releases it's own jolt to help break down the insulating seed coat, which also helps the fruit to produce more chemo-electricity, in a positive feedback loop.

Chomp

When an animal comes and takes an abrupt, huge bit out of the fruit (particularly if it's fresh fruit from a tree, which isn't yet triggered by a ground impact), it not only produces an abnormally large fruit-shock, but also triggers a similarly large response shock from the seed (which triggers more from the fruit, which triggers more from the seed, etc. etc. etc.). This results in the seed itself popping (like a cross between a popcorn kernel and a Galaxy Note 7's battery) and the crispification of a would-be frugivore.

FOOD

However, if the seed is carefully removed, the fruit itself can be used for rather stimulating cuisine! Electric fruit salads, "Jolt Juice", and many other novel dishes can be made. The intensity of a fresh fruit's current might be unappealing, but you can let it ripen a bit and lose some of its potential. Cultures that regularly eat it tend to have special baskets for carrying and storing them so they can be handled safely, and people with children or pets must be careful to keep the fruits out of reach.

Answer 14

Lots of people have addressed the thoughts on why a plant would want to do this. Lets look at a possibility of How it could be a bug zapper.

Design the Fruit to have some layers, much like a Leyden Jar. A Leyden Jar is essentially a primitive capacitor. Some of them can hold a respectable charge (I remember a high school physics teacher swear loudly and involuntarily drop one when it discharged into his hand)

A conductive outer skin, a layer of non-conductive pith and a conductive inner material and stem. Static would build up from the environment builds in the fruit. The undesirable bird or bug gets too close, landing on or near the stem. He provides a ground for the fruit to discharge into and zap, no more bug or bird.

The fruit will ground and discharge when the fall out of the trees, and then bears or whatever eat the fruit and spread the seeds around.

A totally organic bug zapper, I like it. I hate bugs

Answer 15

A good explanation is not FRUIT that electrocutes you, but some other part of the plant (stems?) that would. Their purpose is to keep the yummy fruit from being eaten before it was mature enough to propagate.

Answer 16

Well, in an imaginary world that you would like a "fruit" that electrify whoever bites it (whether you wanna use it as a bait for later eating or just some random ideas), would be fun to "model it" as:

• A plant that absorbs the electricity in the atmosphere and put it in its fruits to act as a bomb (electricity bomb) to stun their prey before eating it or w/e you want to do. You could check Wikipedia or Google Search in order to get more detailed data related to the behaviour or the "Electricity in the Air".

If you also say that the stun of the fruit, just like the spice, could be something that people will be looking for in order to get feel better or add different tastes to their foods, that could reinforce the argument.

Is interesting to remind you, guys, that when you eat spicy food, you are actually burning your tongue/mouth so the body produces endorphin to make you feel better. I quote this article, that backup that argument:

Chili peppers in particular contain high levels of the substance capsaicin, which causes the burning sensation in spicy food. The chemical has been proven before to work as a topical painkiller for arthritis, and also forces the brain to release endorphins. “The endorphins work to block the heat,” Paul Bosland, cofounder and director of New Mexico State University’s Chile Pepper Institute, told ABC News in 2012. “The body produces them in response to the heat, which it senses as pain.”

So, based on that, you could also say that eating this fruit would have the same effect in human/animal body.

I dont think that I need to reinforce the idea of the plant need to survive and that why it shouldn't hurt the human/animal just because there are so many carnivorous plants in the world that, one plant that actually can stun you before eating you doesn't look that scary or crazy.