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Get me a government grant of 200 billion and I will research it. :)

Greg Baumann


This would prove free will, would it not?


It's theoretically possible and extremely difficult to prove (given accepted rates of change you'd expect it to happen very infrequently) The trick is that it wouldn't happen until animals had evolved a will, which is fairly late in the game.


I don't think you are right (even though i've got about zero evidence to back it up), but I applaud the fact that you've proposed a hypothesis that is falsificatable (can be proven to be wrong).
Prehaps someone should run the test to see wether you are right.

Jason Dumler

Does it still count if the rats choose mates that will generally create offspring with longer snouts? Would they have to kill the ones with shorter snouts...or otherwise deprive them of food?

Courtney B

Gustaf Sjoblom

One could try to rework your hypothesis to "it would be an evolutionary benefit to be able to get offspring that matches your desires". This is 100% correct, it would be a HUGE advantage. So big an advantage in fact that if it had ever happened the species able to do it would utterly dominate earth. I think we can therefor relatively safely conclude that it has never happened.

Kevin Kunreuther

1.)Invite Ben Stein to present the next topic concerning evolution, intelligent design, free will, etc. I'm sure that'll be a very busy day on the blog.
2.)PDB posted:"The rat experiment sounds good, but you'd have to do it for centuries if not millennia to get some results."
Boy, did you get that wrong. First rats, breed year round. Two, one pair of rats can produce up to 14,000 babies a year. Three, it wouldn't even take decades, probably three to seven years when meaningful measurable, and most important, repeatable results can be produced.


Those of you suggesting that Scott's proposal is similar to sexual selection are confused. Sexual selection leads to traits - possibly even otherwise maladaptive traits - because those traits are selected for, not because 'desire' for those traits (fancier tail, for example) results in increased tail fanciness in offspring.

The difference between sexual and natural selection is really just a level of indirection: reproductive success and the heritability of traits depends on increasing the liklihood or frequency of sexual encounters, rather than on surviving long enough to have offspring.

It is acceptable to use the teleological view of organisms 'desiring' those traits in their mates (and offspring), but only if you don't take it literally, but use it as a euphamism for reproductive success. The traits themselves might be a kind of expression of fitness, as some people here have said (only a really first rate peacock can survive despite the enormous tail he carts about) or they might be arbitrary. All that's needed is for the genes coding for the trait in one sex are coupled with the genes coding for desiring that trait in the other, so they are both inherited.

Simon Jester

Occam's razor says "no" is the most likely answer.


"Ooh, look at that long-nosed fella over there Mildrid, he can reach the cheese. I think I'll have his babies".



I don't think you can possibly have thought deeply about the mechanism you propose. It seems orders of magnitude more complex than anything else we have seen in biology. You are suggesting that all kinds of environmental stress is translated into a specific response within the body, specifically denoting that type of stress and that this response is then translated into specific adaptations in offspring, which happen to code for the very thing that would reduce that stress in the offspring, presumably either by modifying sex cells or some jiggery pokery with the developmental environment in the womb, without also leading to any other undesirable changes.

This would be quite a feat. As many have pointed out, 'desires' are highly abstract things. If the mouse can't reach the cheese, in what sense does it 'desire' to have a longer nose so that it can? In other words, where does the information that a longer nose would help get more cheese come from? It seems unlikely that the mouse could draw this conclusion, let alone its genes.

Even if every type of desire could be codified by some set of body responses, where would the information about how to attain those desires come from? Wouldn't it be highly context dependent? If the cheese is up high, might not longer legs or neck be an equally valid solution?

The mechainism is an unfathomably complex one with enormous engineering difficulties, but this doesn't necessarily rule it out as a possible mechanism of evolution.

However, it is also necessary to ask how such a mechanism might evolve by natural selection. The problem is that the mechanism is not directly exposed to natural selection. Although we can see with hindsight that such a mechanism might be useful for survival, natural selection doesn't work like that. In other words, the ability to flexibly respond to an environment through directed changes in the next generation does not seem like something that could be selected for, except possibly under very contrived circumstances.

For this reason, I suspect it is impossible (or at least vanishingly unlikely) for this type of mechanism to evolve by natural selection.

Alex Andronov

The problem with this is simply that it ignores why evolution occurs at the microscopic level. I mean in traditional evolution bactiria and humans evolve in the same way. But unless bacteria have brains I've missed you'll need a theory for that too.

Brendan Mackie

Isn't the giraffe's long neck a product of sexual selection? Male giraffes compete for females by neck-butting each other. Those with longer necks are better at it. Which is why the females have shorter necks. The feeding habits have pretty much nothing to do about it.

And yeah, anything is possible. But... do you have proof? I reckon natural selection has more explanatory power than aspirational selection. Is there evidence of this happening? A mechanism?

Dinky mcbutthose

I might agree with ou except then i would go to hell. God made long necks and anteater snouts and small penised cartoon monkies.

debate over.

frances a.

I'm no sociologist but it seems to me you could test your hypothesis on humans, albeit with a strictly observational study. Have a group of pregnant women document their personal situations, dreams, aspirations, goals, intentions, wishes, desires, et cetera throughout their pregnancy, then observe their off-spring throughout their respective lives to see how they turn out and whether any of their mothers' aspirations, wishes, desires, et cetera manifest, while allowing for parenting techniques, environment, and all that jazz. No idea about a control group, though, unless you used test tube babies. Can we even grow human babies in a lab without a borrowing a womb for ~9 months yet? (Or perhaps you could swap a few infants in the baby room at the hospital. Ethics regulations would probably get in the way there, though.)

Granted, this would take several decades for a big enough picture, but that's a great deal shorter than the millennia previous posters have suggested.


Your rat experiment is flawed. There is an evolutionary explanation for the behaviour that you say would prove your theory: Rats who mutated longer snouts could get the cheese and have more spare time to have babies that would have long snouts.


This would be really hard to test, much less prevent unintended consequences. Take the gender issue. Diet might help you have one gender, but if the mother is really stressed, she's more likely to have a girl or a miscarriage.

Or take your long neck theory. We'd be talking about not only a longer neck, but also internal changes that would have to occur simotaniously. (I butchered that one) In order to get his neck that high, he'd also have to have the heart and blood vessals as well. Likewise it'd have to occur slowly where the animals needed to have longer necks for some reason and not too fast where a sudden lack of necklength is going to kill you.

The trick to it would have to be is if the males (or any female animal that can produce new eggs on demand, something human females can't do) had some way of recording their current events in their reproductive materials such that their genetic info would tend to carry the best codes for the situation.

I think it would be a great way to change your genetic code on demand, however gender tendancies of birth are another matter. In several species, enviromental changes effect gender. In humans this works by in which the female's body is producing conditions more or less favorable to one gender of sperm or embryo.


I like your theory Scott, but have 1 question.( & then other, subsequent questions)

How did this theory apply before animals had evolved brains? Did they aspire to grow brains and therefore get them? Indeed, can creatures without brains aspire to be anything?


Ignorance is not bliss.

The Teaching Company has an awesome biology course. There are 72 thirty minute lectures but lectures 4 through 11 will teach you what you need to know about microbiology so you won't be embarrassing yourself by making wild ass guesses. Why go through life stupid when the cure is so easy.


Of course it does because aspirations will influence the social groups you mix with and what kind of mate you choose.

Most mammals are probably smart enough that this could apply to them to a small but statistically significant degree with out needing to evolve a new mate selection strategy. But of course anything non-mammalian wouldn't be smart enough so we could rule out the influence of aspiration.

Dom P

Giraffes have long necks because they have long legs. Their necks are proportional.

If you have long legs, you need a long neck (or a trunk) so that you can drink without kneeling.

Baby giraffes would be in trouble if they needed to access high-up food. Hardly an evolutionary advantage.


I've theorised myself a version of this that happens in- utero, after reading an article that describes the synapse-pruning in the brain of a foetus in the few months before birth.
As far as I know, little is known about what causes particular synapses to be pruned, as within a womb evironmental conditions would assumingly be of little influence.
Clearly we're getting beyond current scientific theory if we are going to talk about 'desires' or 'energies' of the mother influencing the development of the foetus..but it doesn't seem that much of a stretch in my mind, at least anything over 'chance' should be explored.
I am particularly interested in how the synaptic connections are formed in the first place - does a foetus have a physical 'memory' of sorts that develops in the early months, only to get 'fixed'or 'formed' through the will of the mother?



People who study the natural history of giraffes have observed that they don't really eat from just high up in the trees. More often, rather, they eat from the lower limbs.

So why the long necks? They're actually secondary sex traits (e.g., tails of male peackocks, antlers/horns, male lion manes, and German cars).

Females giraffes choose mates with long necks for the same reason female birds choose males with pretty colors - these animals can survive, are tough, and good providers, because they can take care of themselves AND avoid death due to bad camouflage or pretentiousness (German cars).

Male giraffes even use their necks to wrestle one another in direct competition to mate with females. This also explains why females have shorter necks, similar to female birds having drab colors, and female lions lacking manes (females don't compete for the attention of males, rather choose the biggest, fastest, best singers, or ones with the most endurance). If only we could get German car drivers to smash into one another like big horn rams to gain the acceptance of the opposite sex. I'd pay to watch that.

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