This past summer I had two cherry tomato plants that popped up (unannounced) in my flower bed. They produced a lot of delicious tomatoes. Today I picked a tiny ripe tomato from one of them, about the size of a good sized round bean. I’d like to know if the seeds from this tiny tomato will eventually produce more of the same. It could revolutionize salads.
The size of marbles? Had them in a salad in a restau. I’ve also seen them in tomato plants stunted by lack of water (or lack of care in your case I think.) But not as an entire harvest.
A quarter the size of a marble. The rest of the tomatos were normal cherry size, and I tended these plants like a mother would to her babies.
The seeds from the tiny tomato are no more nor less likely to breed further tiny tomatoes than are any other fruits from the same plant. The size of all of the fruits are determined by the same genetics, so if the plant could produce normal cherry-sized fruits, its daughter can too.
^^
Not meaning to rib. I just assumed you treated it as a weed as it sprang unintentionally.
No offense taken. Between the trees in my and my neighbors yards there is little sunlight to have a proper vegetable garden. These plants were a gift.
I read once that the apples we have today are the result of bears in Asia choosing the sweetest and biggest fruits from crab-apple trees, thereby spreading those seeds (along with fertilizer), and so on.
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Thank you Clee for your post. Saved me twenty years of inbreeding tomatos to accomplish what already exists. Now I can turn my energies towards a bite-sized watermelon.
Please provide a cite for that, I want to read that paper and how it was figured out.
I find that very interesting. Zero snark.
Capt
I hate to break it to you but: http://www.pepquinomelons.com
But hey, maybe you could breed tiny farm animals for smaller, more healthful proportions!
Not practical. Tiny cows would escape and wreak havoc. I’ll stick to vegetables.
It’s my understanding that many farm animals are already smaller than their wild counterparts. Not by that much, mind you, but enough to make them easier to wrangle.
Here’s an example of a “wild” cherry tomato touted for flavor (I grew it once and was not overly impressed).
Volunteer cherry tomato plants that produce very small fruits are likely from hybrids with characteristics showing reversion to a wild-type form. Maybe the OP has lucked onto a type that is actually superior to what’s on the market. A fortune could still be made. 
Just to expand on what Chronos said, one tomato plant is one organism, and all the cells of a single organism are the same, genetically. If you take two tomatoes from one plant, they’re going to be genetically identical. Any difference in size between two fruits on one plant is most likely environmental - not enough sun, too many other nearby fruits soaking up the nutrients, etc.
It is not entirely impossible that a new mutation happened in a cell that gave rise to the tiny tomato that caused its odd size, but it is extremely unlikely.
Now, that said, if you took all the seeds from a given plant, they would not be identical, thanks to independent assortment in meiosis and recombination and whatnot. But barring that unlikely mutation, as Chronos said, plants grown from seeds from the small tomato are most likely going to look just the same as plants grown from seeds from other tomatoes from the same plant.
Choosing fruit from the trees with sweeter apples, perhaps, but not choosing the sweetest apples on a given tree.
There are several types of currant tomatoes available to grow, all of which are likley to be the smallest tomatoes you’ve ever seen. They are all very prolific and lot of fun to use in salads.
The X factor here is whether your tiny tomato’s mommy and daddy were open pollinated or hybrids. The offspring of crossed hybrids generally do not breed true. If you save the seed, you’ll probably get a mix. Some of the plants will produce tiny tomatoes. Some won’t. I say save the seed and give it a try. You’ll be no worse off than if you hadn’t saved the seed.
Right, the seeds will in general be different. But they won’t correlate with the size of the fruit they come from. All we really know is that you have a plant capable of producing at least some tiny fruit. Some of the seeds from that plant might have the gene for that trait, and some might even have it stronger than the original, but those tiny-fruit-seeds could be in any of the fruits.