There were two details that you left out that bothered me. At first I felt like I was nitpicking, but then they two coalesced and I felt better describing them.
You say that animals have coevolved with plants, but you I think you should have spelled this out more. You say that the plant puts more energy around the seed, but you don’t say that this is a fruit. The point of a fruit is not to be higher energy to than a seed, just so that it is more likely to be eaten (Are there any examples of this, outside of agriculture?). The point of a fruit is to separate out the fruit which is to be digested by the animal from the seed which the plant does not want to be digested. Fruits are wet sugar, the easiest thing to digest. An animal that eats a seed is competing for the same energy as the plant, whereas an animal that specializes in eating fruit may not be very efficient at digesting the inner seed. This isn’t relevant to the coevolution of wheat, which benefits from humans planting seed corn, not from humans failing to digest the wheat.
You mention two methods of making bread without industrial yeast. One is to just leave out porridge, harvesting yeast from the air or the wheat. Another is to get starter from your neighbor. But I think that the most common method, at least historically, is to put fruit in the porridge. Since fruit is easier to digest than seeds, yeast is more common on fruit than on seeds.
The second point seems like an important omission if true. Not having known that originally, I notice that based on the model in this post, it seems like the sort of thing that could likely be true. I don’t think I explicitly mentioned the neighbor method either, though I think it’s another reasonable inference from what I did say.
On your second point, it seems like while fruits often store food packages outside the seeds, grains grow a bunch of similar modules with uncertainty about whether they’ll be used as the reproductive payload or the calorie surplus that persuades the symbiote to spread the reproductive payload. My guess would be that before explicit agriculture, some grasses did well around humans because there would be the occasional undigested or otherwise scattered seed by accident.
Overall it seems like you’re pointing at something important on the object level here, and I appreciate the engagement with the *kind* of explanation I was trying to give.
I’m not a biologist, but I think it would be pretty difficult to tell whether fruits are intended to encourage animals to eat them or to protect the inner seed. But the energy in an avocado is primarily stored as fats, and it’s generally thought that they were eaten by now-extinct Central American megafauna. (And it’s common to stick avocado seeds with toothpicks to get them to sprout...)
There’s also the chili pepper, but I don’t know if anyone’s studied digestion of pepper seeds in birds (which aren’t sensitive to capsaicin) vs. mammals (which are). It may be that chili peppers evolved to deter mammalian but not avian consumption because the mammalian digestive tract is more likely to digest the seeds, rather than (as the common explanation has it) because birds disperse the seeds more widely.
For chili peppers, I, too, prefer the second explanation. I think that is the more popular one, eg, appearing in wikipedia. More specific than digestion, is the theory that it is to avoid the grinding teeth of mammals. I don’t know if the specific case has been studied, but the general topic of how much various fruit-eaters digest seeds has been studied. Presumably there is study of how to select cooperative fruit-eaters over defective fruit-eaters.
I am confused by your first sentence. What are the alternative hypotheses? Protect the seed from what? Fruit are certainly lousy at protecting the seed from yeast. I claim that they protect the seed from specialized seed-eaters by encouraging consumption by specialized fruit-eaters. Yes, the avocado is a pretty weird fruit, but it’s still a soft, wet, easily digestible outer coating around a hard, difficult to digest seed. What light does it shine on the question? Your use of the word “but” suggests that it addresses the first question, but I don’t see it, perhaps because I don’t know what the first question is.
I find the adding fruit method interesting, as I had not heard of it before. I had understood the exposure-to-air method to be both the earliest and the most common, which matches my expectation as all the environments people are in have naturally occurring yeast, but not all of them have fruit to add. For example, traditional sourdough explicitly has just water, flour, and salt.
I’m pretty sure the methods of bread making at least in Morocco and Iraq don’t involve adding fruit, which I sort of mentally extend across the Arab-speaking world. Because of its similarity I assume the same of naan. Interestingly Iraq (at least the Baghdad area where I have been) is an easy-access fruit environment courtesy of citrus trees.
On the flip side, I have seen recipes for different sourdoughs that involve adding grapefruit juice to accelerate the process, but in the context I saw it was just for speeding things up. There is also the habit of adding various leftovers, including fruits, nuts, and vegetables to bread, which would probably have a similar effect.
There were two details that you left out that bothered me. At first I felt like I was nitpicking, but then they two coalesced and I felt better describing them.
You say that animals have coevolved with plants, but you I think you should have spelled this out more. You say that the plant puts more energy around the seed, but you don’t say that this is a fruit. The point of a fruit is not to be higher energy to than a seed, just so that it is more likely to be eaten (Are there any examples of this, outside of agriculture?). The point of a fruit is to separate out the fruit which is to be digested by the animal from the seed which the plant does not want to be digested. Fruits are wet sugar, the easiest thing to digest. An animal that eats a seed is competing for the same energy as the plant, whereas an animal that specializes in eating fruit may not be very efficient at digesting the inner seed. This isn’t relevant to the coevolution of wheat, which benefits from humans planting seed corn, not from humans failing to digest the wheat.
You mention two methods of making bread without industrial yeast. One is to just leave out porridge, harvesting yeast from the air or the wheat. Another is to get starter from your neighbor. But I think that the most common method, at least historically, is to put fruit in the porridge. Since fruit is easier to digest than seeds, yeast is more common on fruit than on seeds.
The second point seems like an important omission if true. Not having known that originally, I notice that based on the model in this post, it seems like the sort of thing that could likely be true. I don’t think I explicitly mentioned the neighbor method either, though I think it’s another reasonable inference from what I did say.
On your second point, it seems like while fruits often store food packages outside the seeds, grains grow a bunch of similar modules with uncertainty about whether they’ll be used as the reproductive payload or the calorie surplus that persuades the symbiote to spread the reproductive payload. My guess would be that before explicit agriculture, some grasses did well around humans because there would be the occasional undigested or otherwise scattered seed by accident.
Overall it seems like you’re pointing at something important on the object level here, and I appreciate the engagement with the *kind* of explanation I was trying to give.
I’m not a biologist, but I think it would be pretty difficult to tell whether fruits are intended to encourage animals to eat them or to protect the inner seed. But the energy in an avocado is primarily stored as fats, and it’s generally thought that they were eaten by now-extinct Central American megafauna. (And it’s common to stick avocado seeds with toothpicks to get them to sprout...)
There’s also the chili pepper, but I don’t know if anyone’s studied digestion of pepper seeds in birds (which aren’t sensitive to capsaicin) vs. mammals (which are). It may be that chili peppers evolved to deter mammalian but not avian consumption because the mammalian digestive tract is more likely to digest the seeds, rather than (as the common explanation has it) because birds disperse the seeds more widely.
For chili peppers, I, too, prefer the second explanation. I think that is the more popular one, eg, appearing in wikipedia. More specific than digestion, is the theory that it is to avoid the grinding teeth of mammals. I don’t know if the specific case has been studied, but the general topic of how much various fruit-eaters digest seeds has been studied. Presumably there is study of how to select cooperative fruit-eaters over defective fruit-eaters.
I am confused by your first sentence. What are the alternative hypotheses? Protect the seed from what? Fruit are certainly lousy at protecting the seed from yeast. I claim that they protect the seed from specialized seed-eaters by encouraging consumption by specialized fruit-eaters. Yes, the avocado is a pretty weird fruit, but it’s still a soft, wet, easily digestible outer coating around a hard, difficult to digest seed. What light does it shine on the question? Your use of the word “but” suggests that it addresses the first question, but I don’t see it, perhaps because I don’t know what the first question is.
I find the adding fruit method interesting, as I had not heard of it before. I had understood the exposure-to-air method to be both the earliest and the most common, which matches my expectation as all the environments people are in have naturally occurring yeast, but not all of them have fruit to add. For example, traditional sourdough explicitly has just water, flour, and salt.
I’m pretty sure the methods of bread making at least in Morocco and Iraq don’t involve adding fruit, which I sort of mentally extend across the Arab-speaking world. Because of its similarity I assume the same of naan. Interestingly Iraq (at least the Baghdad area where I have been) is an easy-access fruit environment courtesy of citrus trees.
On the flip side, I have seen recipes for different sourdoughs that involve adding grapefruit juice to accelerate the process, but in the context I saw it was just for speeding things up. There is also the habit of adding various leftovers, including fruits, nuts, and vegetables to bread, which would probably have a similar effect.