simian

AAARRRRRGGGGG!!!!!

Yes, transgenic crops use genes not in the plant "naturally". It can be arrived at by "conventional" means as well, but with much, much less precision.

Case in point: soybeans that are resistant to Roundup herbicide. Yes, Monsanto transferred a gene to soy that allows resistance to Roundup. GMO, labeled as a bad food. What was done? Insert 1 known gene.

Alternative: clearfield soy. (I have not checked up on this particular plant, but have heard some info on it). Take a lot of soy seeds. Put them into a vessel where they are exposed to radiation. Test for any resistant to Roundup. "Traditional" crop, labeled as good food. What was done? Mutation of at least one gene, as well as an unknown number of others.

Canola is the result of mutagenic chemicals and radiation to knock out "bad" genes. But it is a "good" food, and can be labeled organic.

Clearfield sunflowers - result of poor crop management practices. Now there are IMI herbicide resistant wild sunflower (not there in the "native" population, novel mutation) that can be bred into domestic sunflowers. "Good" food, can be labeled organic.

As for the idea that older varieties of plants have no pesticides in them, why do you think the world is not overrun with insects - something is keeping them from eating all the fruits/vegetables. It may not be an extremely effective pesticide, but it is a pesticide never the less.

Simain

NialScorva

How about the Gila monster, who has venom that it delivers by meerly chewing? You don't need to evolve a delivery mechanism first, there are many viable pathways. Get a large herd of cattle, check to see which cough up the most stomach acid when they chew cud. Select for that for a couple thousand generations. Then start selecting for those that are likely to bite. Do that for a couple thousand generations (probably switching back and forth between the two). Now you have a population of cattle that bite and tend to have stomach acid in their mouth. I think you can fill in the rest.

Sure they are. You don't *rely* on them, normally, but they are without a doubt part of the process. If something comes up in your favor, you select for it. If something comes up to your disadvanage, you select against it. If it neither helps nor hinders, then you don't worry about it. That's part of what selection is.


Now the real question of GE is "can we engineer people to subsist entirely upon crow within your lifetime?"

Corwin

Actually gila monsters do nothing of the sort. Do the research next time.

Gila monsters have no direct injection method for their venom. They DO however, have venom glands.... same as any venomous creature. They rely on gravity to effectively dribble the venom into the wound. To put it simply, they bite, then flip over.

Simply regurgitating stomach acid into your mouth and biting isn't going to deliver anywhere near enough toxin to actually kill something. In addition, by attempting this you're breeding an animal that will injure itself every time it tries to bite.... (stomach acid is nasty stuff) and most likely won't have enough acid to digest its food after it's used enough to kill it's prey. Not exactly the most successful species in the world.

The example you're looking for, or at least the one that's closest to what you're looking for, are komodo dragons. They aren't actually venomous, but their mouths have enough bacteria in them that any serious bite is just about gauranteed to get infected and kill its prey.

In addition, once you get into 'thousands of generations...' guess what? You're well outside the realm of 'selective breeding.' You've just crossed over into there being effectively no difference between what YOU are calling 'selective breeding' and natrual evolution. At that point of COURSE random mutation is going to play a role.... and if you're extremely lucky.... (and pray hard enough!!! Never forget that one!!! ) you MIGHT get the result you're looking for. Pigs might suddenly sprout wings and flap off too. Neither one is terribly likely.

You're making the mistake of assuming that because mutation can cause changes in a species over time, that it can cause specific and desired changes. This is not the case. Mutations don't care. They just happen. The odds of you getting the one you specifically WANT is billions to one against. (This is the core mistake of many creationist arguments actually.... ironically enough. Like you, they assume that selective breeding is the same thing as natrual evolution.)

By the way..... crow, like most birds, is quite edible. Doesn't happen to be on my menu today tho.

NialScorva

First, I am aware that the Gila Monster has venom glands. You brought up delivery mechanisms as a *seperate* issue from the poison source, and I provided the delivery mechanism.

Secondly, I do not rely on random mutations, as Patrick mentioned, you can select for a trait that falls on a continuum, in this case the amount and frequency of stomach acid regurgitated. Novel mutations to the goal would just be a bonus.

VonEvilstein

Biological food always makes me laugh! The only non-biological food I ever recall buying is salt.

Dr Rick

Foods produced using recombinant techniques usually differ from their conventional counterparts only in respect to one or a few genes, as opposed to the use of traditional breeding methods which mix thousands of genes. The food safety considerations for GM crops are not much different from conventionally bred crops, and very few of the latter have been subject to any safety testing though the former always are before release. There have literally been trillions of GM plants grown and consumed worldwide, and despite the many commentaries and opinion pieces appearing in the lay-press touting the "potential" dangers of GM, there is not one unique adverse affect reported anywhere in the medical literature from any of them.

Rick

Mageth

You're making the mistake of assuming that because mutation can cause changes in a species over time, that it can cause specific and desired changes. This is not the case. Mutations don't care. They just happen.

No one has made the specific argument you're arguing against. However, mutations can cause desirable changes, e.g. resistance to pests, larger fruit, more fruit, drought tolerance, color, taste, etc. The wise farmer is obviously looking for any such desirable mutations; in other words, a farmer is looking for desirable changes in general, not for any specific change. (note: here I'm talking more about "primitive" farmers, who did most of the work in developing most of the crops we have today, and not modern industrial farming, where individual plants in the field are rarely viewed individually, though I would assume if a desirable mutation is detected, it would still be exploited).

The odds of you getting the one you specifically WANT is billions to one against.

Perhaps, but the "odds" of desirable mutations occurring, over a large population of cultivated plants, is much, much higher, to the point where they can and do happen quite often. And again, "the one you specifically want" is not what's being looked for; it's desirable changes in general.

(This is the core mistake of many creationist arguments actually.... ironically enough. Like you, they assume that selective breeding is the same thing as natrual evolution.)

Huh? I thought creationist generally discounted "evolution" in general, sometimes supporting "microevolution", and claimed selective breeding is merely selecting for traits already there. (Hmm, wasn't it you making that argument?)

IMO, your argument are the ones that have been bordering on creationist arguments, e.g. the "rarity" of mutation argument, the "just as likely to be detrimental as beneficial" argument, and the "merely selecting for traits already there, mutation plays no part" argument.

Corwin

That's the core argument isn't it?

In selective breeding, you have a specific goal. Evolution doesn't.

'Desireable' alone is insufficient with selective breeding. Evolution doesn't care about specific traits. In that case, 'whatever works' is sufficient, and you have time to wait around for random mutations. Not so with selective breeding where you're working toward a desired result OTHER than simple survival and procreation.

Mageth

Again, no one had to "wait around" for random mutations, no one is looking for a particular mutation. You cultivate what you have, and select for beneficial traits (whether the "traits" are "already there" (which gets you only so far) or occur by random mutation (which takes you farther)). The desired result is a better crop, not a particular mutation, and any number of changes (mutations) can lead to better crops.

A trivial example is rose cultivation (not food-related, I know, but allow me the analogy; I think it's valid). Many of the exotic roses we have today are the result of naturally-occurring mutations (induced mutations are also used), artificially selected for when they occur. There's an area of rose breeding referred to as "mutation breeding." Rose breeders are not generally looking for any particular mutation (with the possible exception of the legendary "black rose"); the mutations are recognized as "desirable" when they occur.

Here's another parallel from the world of bird (finch) breeders.

And more directly to the subject, there's this interesting article about a graduate student's (in plant biology) project studying naturally-occurring mutations in corn, in which she says:

NialScorva

The core is how selective is "selective" in "selective breeding" with respect to the target areas of the genome that you're trying to affect. With the stuff Mageth posted, it seems that the answer is that it's not very selective at all for most traits.