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Comment by aroch | Hacker News Reader

What exactly is not natural about human-caused selection? As far as the banana is concerned, we're a "predator" that increasingly preys on banana plants which produce fewer seeds but bigger, sweeter ovary. It's a directed, inverse selection pressure. There is nothing "not natural" about human-directed selection for agriculture.

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Being an intelligent, highly adaptive, and prolific species means that we need to exercise a degree of self-restraint. In part because we are able to over-select through cultivation for genetically homogenous food sources, that are uniformly susceptible to even more adaptive microorganisms.

Yes, the increasing homogeneity of cash crops (ie. corn) is problematic but has nothing to do with my question.

I perceive certain cultivars as being less "natural" than harvested wild varieties. But you're right of course, that the selection process is in no way synthetic.

Bananas don't have any seeds - they're a sterile hybrid, and normally propagated via cuttings. http://www.damninteresting.com/the-unfortunate-sex-life-of-t...

Sterile hybrids are not a new thing nor are they something that only occurs with human intervention. Darwin's finches routinely mated in pairs that produced sterile hybrids. Vegetative reproduction (ie budding or from cuttings) is also quite common in plants -- there are several plants that vegetatively reproduce by only their leaves. Human aided vegetative propagation is no different from herbivore aided propagation caused by a herbivore burying part of a vegetatively reproducing plant

The several varieties of bananas that you'll see in the store are most definitely caused by human intervention (actively trying to cross slightly different plants to produce a new hybrid) and propagation. Normally hybrids die out in the wild.

Also, once you have a sterile hybrid, there's not much in the way of selection pressure. And since bananas are clones, there's nothing for the selection pressure to act on.

Not quite true, if I understand you correctly. Clones are a form of asexual reproduction, not that different in principle from what is observed in bacteria. So plant clones do undergo mutation and natural selection.

I don't know about bacteria, but a banana variety is all essentially the same plant, propagated from a central stock. Have a look at the controls around planting and growing your own bananas, it's all red tape, permits and extremely fascist:

http://www.backyardbananas.com.au/faq.html

http://www.daff.qld.gov.au/plants/fruit-and-vegetables/fruit...

And for very good reason: every banana of a variety is susceptible to (eg.) a virus outbreak - there won't be any pockets of genetic variability like you would get with potatoes or citrus. If anything that affects bananas becomes widespread - no more bananas.

I was replying specifically to "since bananas are clones, there's nothing for the selection pressure to act on." That's not correct reasoning, since the DNA in plant clones can mutate, and thus, plant clones are susceptible to selection pressure.

In theory, yes - but mutation rates of clones are going to be very, very low. Bananas are also grown from a central stock to control disease, so even if there were a mutation, all the bananas are going to mutate identically.

Bacteria reproduce in all sorts of bizarre ways, including swapping DNA from other bacteria, editing their DNA, etc., so it's not really related.

I think we can all agree that what's happening with bananas is not a healthy state of affairs. I was just trying to clarify that asexual reproduction doesn't exclude natural selection, and was using bacteria as an (admittedly not perfect) analogy.

I guess if you had simply said that there's virtually no selection pressure, you wouldn't have triggered my nitpick reaction. :)

> What exactly is not natural about human-caused selection?

It's, by definition, artificial selection.

With your "logic" everything is natural.

Nothing about artificial selection in this instance is unnatural.

Well, it's probably a little more complicated than that. Yes, if we define any actions taken by humans as "artificial", then it's "un-natural".

BUT, putting selective pressure on a plant to be more delicious and/or possibly nutritious is as natural with humans as it is with much of the animal kingdom. The edible fruit has an evolutionary incentive to taste better, and therefore produce more offspring.

Trying to assign a good or bad grade to this is exactly the naturalistic fallacy.

A name is not a definition. Artificial selection is a subset of natural selection. Humans are natural components of the environment for the thing being selected.

With no definition for "Not natural", you render the word "Natural" essentially meaningless- turning it into a "valid" adjective encompassing everything.

Which, for reasons that should be obvious, makes it problematic as a word for promoting certain types of food. Since humans are components of the ecosystem, twinkies are technically "natural", right?

"Natural" has more than one definition, dependent on its context. In some definitions of the word "natural", yes, twinkies are technically natural. In the more colloquial senses they are not. I prefer the more technical sense: since humans are derived from nature, they are natural, hence anything they do is natural. Unless you subscribe to some sort of man/nature metaphysical duality I don't see how you can argue that humans are not natural.

Twinkies are made from the same atoms as everything else. A glucose molecule assembled by a hypothetical atom arranger is indistinguishable from one synthesized in an organism. Twinkies are ultimately derived from nature, just as humans are ultimately derived from nature. Twinkies are a result of the congruence of multiple ideas that have evolved by natural selection. Among others, the ideas of refining and processing the chemical products of plants and animals, and how to make a twinkie-like baked good. Twinkies did not spontaneously appear in a vacuum.

Regardless of the words we use, the core idea of what we term "artificial selection" is a subset of the core idea of what we term "natural selection".

but the context is food labelling, not technical/philisophical argument!

Let's address THAT definition of "Natural" without getting sidetracked by irrelevancies.

Artificial is a subset, not the complement of natural.

I initially disagreed with your arbitrary cutoff point for what's natural, but your condescension and lack of explanation of your argument in this post really sold me.

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