Biological limits on pepper arms race?

In summary, the pepper pod contains the seeds that contain the hottest part of the pepper, and the seeds must be viable in order for the pepper to be hot. The seeds are also the part of the pepper that tend to be destroyed by mammals, which allows the peppers to be dispersed more easily.
  • #1
PAllen
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In the last year or so, there has been a breeder arms race to produce the hottest pepper. The peak has gone up a little over 1 million scoville to over 1.5 million scoville in a short time. Since pure capsaicin is 16 million scoville, there is a well defined upper limit. I don't know the biological function of the pepper pod (as opposed to the seeds). The seeds obviously have to function as seeds, yet are often the hottest part of the pepper. So, to all the Biology specialists here, I invite speculation on what would set the limit on capsaicin percentage? [ Assuming the plant must be viable and able to be cultivated from seed.]
 
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  • #2
[According to http://en.wikipedia.org/wiki/Capsaicin, the actual seeds don't contain any capsaicin. Also capsaicin has no effect on birds, which have different biology from mammals.

Since mammalian teeth tend to destroy the seeds (again unlike toothless birds) all this may be a mechanism that hinders mammals from chewing up the seeds, while letting birds disperse them.
 
  • #3
It's hard to know, really. There are a lot of variables. My habaneros (Red Savinas) did poorly last summer because of the combination of too much water, then drought. As a result, I got almost entirely green (immature) peppers and the heat of the resultant chili relish was on a par with that made of mature jalapeno peppers in previous years. Chilies love lots of sun and heat (warm soil) and not too much nitrogen in their soil. Cloudy, wet days can kill their capsaicin content in short order.

If Rhody keeps tinkering with growing conditions, he can probably give you some feedback on relative heats. I think you'd need a really nice greenhouse set-up and lab to explore the upper limits.
 
  • #4
AlephZero said:
[According to http://en.wikipedia.org/wiki/Capsaicin, the actual seeds don't contain any capsaicin. Also capsaicin has no effect on birds, which have different biology from mammals.

Since mammalian teeth tend to destroy the seeds (again unlike toothless birds) all this may be a mechanism that hinders mammals from chewing up the seeds, while letting birds disperse them.

I recall reading that capsaicin affects only mammals, and the same hypothesis.

Birds get about and cover more area then most mammals. As seed dispersion is important to the plant, a deterrent to mammals, yet not affecting birds, allows the seeds to be carried further.
 
  • #5
BTW, the Chemical Injury specialist (MD teaching at Dartmouth-Hitchcock) treating me for MCS suggested that since I really love peppers, I should try to desensitize my mucous membranes with capsaicin in a controlled way over time. I thoroughly pulped a bunch of whole habanero chilies, soaked them in Bacardi 181 for days then extracted the resultant juice. Every day, I would gargle with that juice several times, gradually (or not so gradually, at times) increasing the heat by increasing the amount of extract or decreasing the dilution of the dose. It didn't help my MCS one little bit, but I got a good shot of "cap" several times a day for weeks, just trying it out.
 
  • #6
I have some vodka in which I soaked a habanero and a serrano, it is quite powerful.
 
  • #7
Insanity said:
I recall reading that capsaicin affects only mammals, and the same hypothesis.

Birds get about and cover more area then most mammals. As seed dispersion is important to the plant, a deterrent to mammals, yet not affecting birds, allows the seeds to be carried further.
I had a conure that absolutely loved chili peppers. When I would put treats in the "treat-dish" on the perch I had made for her, she would immediately pick out and eat all the chilies. Seeds, dried nuts, etc could wait - she had to have the peppers.
 
  • #8
PAllen said:
The seeds obviously have to function as seeds, yet are often the hottest part of the pepper. So, to all the Biology specialists here, I invite speculation on what would set the limit on capsaicin percentage? [ Assuming the plant must be viable and able to be cultivated from seed.]
Been bitten by the hot pepper wars, eh ? Asking logical questions as to the upper limits on capsaicin content and potency are logical questions to pose. My best understanding to date, I don't have links to support it with at the moment, is that the progenitor (tendency to differentiate) into a different type of cell led to the hot varieties of peppers (bhut jolokia, trinindad scorpions, etc...). I have read that the genetic mutation that occurred sometime in the middle to late 1800's was responsible. If you want a substance that is close to capsaicin, but is exponentially hotter than it, have a look here: resiniferatoxin (ultra potent capsaicin analog). I posted on it in Turbo's Hot Stuff thread. If you look at it's chemical composition, you can see how the molecule is similar to capsaicin. resiniferatoxin (mixed with other chemicals) is being tested as an end of life pain treatment for people in severe pain because of cancer (this is covered in the link). I am not a biologist or chemist but I believe the physical composition of the capsaicin molecule, as you mentioned at 16 million scoville dictates this.

Turbo claims and I buy it, that the majority of the heat comes from the placenta (membrane that holds the seeds), more membrane, more capsaicin, more heat ? Lastly, I have reported that low lying peppers on the branches which have been stressed due to heat, lack of watering, followed by sufficient watering to allow for recovery creates peppers that have more heat. I have never tested this theory, but believe someone with sufficient resources easily could, if they chose to do so. I have seen video's where you can see the oil from the capsaicin glistening on the inside of the plant as well. I have to believe these peppers are hotter than those that have less dense placenta's and no excess oil on the inside of the pepper.

Rhody...
 
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What is the "pepper arms race" in terms of biological limits?

The "pepper arms race" refers to the evolutionary competition between plants and herbivores, specifically in the case of pepper plants and their ability to produce spicy compounds as a defense mechanism against herbivores.

What are some examples of biological limits in the pepper arms race?

Examples of biological limits in the pepper arms race include the maximum amount of spicy compounds a pepper plant can produce without negatively impacting its own growth and reproduction, as well as the maximum level of spiciness that herbivores can tolerate before avoiding the plant altogether.

How do these biological limits impact the pepper arms race?

The biological limits in the pepper arms race create a delicate balance between the defensive capabilities of the plant and the tolerance level of herbivores. If the plant produces too much spiciness, it may harm its own survival, but if it doesn't produce enough, it may become an easy target for herbivores.

What factors influence the biological limits on pepper plants?

The biological limits on pepper plants are influenced by a variety of factors, including genetic variation, environmental conditions, and interactions with other species. These factors can impact the plant's ability to produce spicy compounds and the effectiveness of those compounds in deterring herbivores.

Can the biological limits on pepper plants change over time?

Yes, the biological limits on pepper plants can change over time due to evolutionary processes. As herbivores adapt to tolerate spiciness, pepper plants may also evolve to produce stronger or different spicy compounds, leading to a never-ending arms race between the two species.

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