An ID hypothesis: Front-loaded Evolution

"Course" is singular, "trajectories" is plural.

This is not a mere grammatical quibble, I think there's a point that needs addressing here by you or by anyone else with a system of orthogenesis. If the course of evolution is preprogrammed into the first species, then how did its descendants evolve into a lobster and a giraffe? It can be preprogrammed to do one or the other, but how both? How do the same set of genetic instructions tell identical organisms: "Now, you evolve this way but you evolve that way"?

What are your thoughts on this?

So it might be optimal ... based on criteria that we haven't discovered yet?

Well yes, and the aliens might descend in their spaceship and say: "Yeah, you got us, we bukkaked your planet with directed panspermia". But maybe we should confine ourselves to the evidence we have now rather than evidence we might discover in the future.

Given that local optimization is exactly what evolution does, no it doesn't, particularly.

Could have, perhaps. But unless you can say would have, which you can't, that's not much of a point.

According to your own scheme the LUCA could also have had a thoroughly sub-optimal genetic code, programmed to get better and better in its descendants as time progressed. Why not? So apparently even being able to look at LUCA would not distinguish between the two hypotheses. Perhaps you should think of something that would.

One usual case made against front-loading is that while a gene was waiting to become useful, it would be turned into nonsense by genetic drift. I note with pleasure that you have proposed that these genes would be doing something else useful until they were converted to different genes by some pre-programmed process.

But then what about the genes that pre-program the process? To take a concrete instance, the genes that say what genetic changes must be made to turn a land animal into a whale.

Now, these genes themselves must have been doing something else all the time before whales evolved; for two reasons. First, if they'd been saying all along: "Now evolve into whales" then we'd have got whales much sooner. Second, because if they hadn't been doing something, then they themselves would have been turned into nonsense by genetic drift.

But then we need a third set of genes to tell these genes to turn into genes telling other genes to turn into whale genes. And these genes must have had a function other than that, for the same reason that the turn-into-whale genes must have had another function.

Which means that there must have been a fourth set of genes affecting the third set of genes ...

And so on and so forth.

Timing

And then there's the question of timing. How do the genes know: "OK, now it's whale time!" Whatever the genes were for making whales evolve, they were, by your hypothesis, always present from LUCA on down. How do they know when to spring into action? Must there not have been a causal factor external to the genome, causing changes in the genome, to make it start producing whales?

Branching

You haven't answered my question about this, so let me ask it again. According to your hypothesis, LUCA must have had genes to turn it into a whale, and a spider, and an oak tree, and a camel. So what decides which it will actually do?

Ultra-Lamarckism

The only way out that I can see for you is a sort of ultra-Lamarckism. The genes should be able to look around themselves and say: "Hey, I'm in a desert. Better turn into a camel!"; or "Hey, the dinosaurs have gone extinct. It's time for adaptive radiation of mammals!" or "OK, lobsters have been done, so I'd better turn into a tree instead" and change accordingly.

But we have no evidence that genes can respond to environmental feedback in this way. Indeed, where would be the feedback? How could the prospective ancestor of trees know about the existence of lobsters?

Meanwhile we do have known mechanisms that explain ordinary Darwinian evolution.

Edited by Dr Adequate, : No reason given.

Well, speaking for myself, I would especially like you to respond to my points.

But it doesn't really matter. So long as eventually you get round to explaining your ideas by and by, that's fine. So long as you keep on trying to get round to this or that explanation of your idea, no-one really cares if you'll produce the explanation right now, right away, or later. Do it in your own time.

We evolutionists may be a bit mean in some ways (I know I am) but I think we'll all give you as much time as you like to think of your own hypothesis.

Wait ... scientists are disagreeing about something? This has hardly ever happened before.

Seriously, you wish to turn biology on its head and show that our most fundamental ideas about it are wrong. I admire your ambition. But you cannot achieve this with reference to evidence that is itself speculative and unproven. According to your hypothesis (if you fudge it a bit) it would be jolly nice if the genetic code was globally optimal. But no-one has proved this to be the case. The fact that some people have speculated that this is the case is not a reason to throw over Darwinism and start believing in front-loaded evolution instead.

No, no, you misunderstand me. Let's hypothesize that they're both front-loaded. Fine. But at some point branching has to take place. One lineage has to go one way and do photosynthesis, while the other goes the other way and does hemoglobin. Now this itself, on the face of it, cannot be preprogrammed. The reason why one lineage develops one way and another develops in another way cannot be the result of their common genetic heritage.

So what, in your scheme, does explain it?

Actually, I think it is.

Now, it is perfectly true that if someone claims that such-and-such a thing occurs, or has occurred, then it is not a conclusive argument against this claim to point out that they have no theory explaining how it occurred. To take a trivial example, I've seen Penn and Teller do their bullet-catching trick. I have no idea how they did it. I'm still certain that I've seen them do it.

But this is not like the situation that we are in. We agree on what happened: life evolved by radiation from a common ancestor. What you are trying to do is produce a theory explaining that fact. So it is actually a valid criticism of your theory to point out that it does not in fact explain the things that it's meant to explain. That's the whole point of a theory, that's what theories are meant to do. They're meant to explain the facts. If it doesn't do that, it's no good.

Well, this would be a bit of a climb-down. Are you going to give up on common ancestry?

But you're still not drawing a picture.

This "deletion event" happens to plants, but not animals. When they start off with the same genome. What causes this to happen?

If you want to stick with common ancestry, then there must be some causal factor other than the genome that makes the "deletion event" occur.

Well, what is it?

If you do wish to abandon common ancestry then we have a whole 'nother discussion on our hands.

Well, you know, if you want to develop the hypothesis, and you find you need another few years to get it right, then you go for it. As I said, I do admire your ambition. You're almost certainly wrong, but science would not progress unless people pursued seemingly crazy ideas. I've pursued a few of those myself.

But, you can't expect anyone to accept your ideas when they're in their present half-formed condition. All I can do is wish you the very best of luck. But if you can't explain the evolution of the eye, then presently we have to say that your hypothesis has failed to do what it is meant to do, namely explain evolution.

I didn't say that the causal factor needed to be "special". I just said that there has to be one. Two lineages evolve in different directions. This cannot be solely caused by the same gene passed down from the same common ancestor, or they'd both evolve in the same direction. There must be another causal factor.

Well no they wouldn't, 'cos of not having a common ancestor. They might be genetically similar, but they couldn't be genetically related.

He may have been succinct, but he was also wrong.

Something has to make the difference. This something, by your hypothesis, cannot lie in the genome. Where, then, does it lie?

I didn't say it wasn't. But if that's what Genomicus thinks, then he should say so. What I am trying to elicit from him is what he thinks this factor is. It cannot be the genome. It must be something else. I want to hear from him what he thinks it is. If he says "chance" then we can continue the discussion on that basis.

OK, that's a new factor in your hypothesis. Chance decides it.

But in that case, shouldn't we stop calling your hypothesis front-loaded evolution, when it is, according to you, just how the dice happened to fall? What I understood by "front-loaded evolution" is that the outcome was inevitable. If, instead, it is random, then perhaps you should think of another name for it.

Then you would have done well to mention this in your OP instead of waiting 'til now.

But if chance is a factor, then in what sense is evolution front-loaded? If it is purely a matter of chance that evolution produced humans and tigers rather than bumblegriffs and hippodores, then where is the front-loading?

If you wish to advocate for directed panspermia, then let's continue the discussion on these lines. But I don't see how you can argue for front-loaded evolution and also ascribe a highly significant role to mere chance.

Ah, I missed this until Percy replied to it.

I was being really really sarcastic. Really, really, really sarcastic.

My point remains. You want to turn all biology on its head. Again, I admire your ambition and wish you luck. But you can't do that with reference to evidence that people don't actually agree is evidence and that many scientists think is untrue. Maybe one day someone will prove that it's true. But until then you can't back up a speculative hypothesis with equally speculative evidence, 'cos that doesn't work.

Using the phrase: "Not meaning to quibble over semantics" does not in fact stop you from quibbling about semantics when that is in fact exactly what you're doing. When I am king, that phrase will be banned along with all sentences beginning with the words: "No offense, but ..." and "I'm not a racist, but ..."

Being king is awesome.