The importance of neutral null for understanding evolution
ncbi.nlm.nih.gov
ncbi.nlm.nih.gov
It means something like "That which is now in a way consistent with that which has been and will be". To me, that's evolution.
This is a reconciliation of philosophy and spirituality that I have found deep joy and peace in. I was raised Christian, and while I was never pressured to be creationist, neo-Darwinism left such a bad taste in my mouth that at a young, naive age, I embraced creationism as a way to rationalize things that my heart knew to be true.
But by the end of high school, I had come to terms with the beauty and depth of evolutionary theory. Thanks to more ecological versions of evolutionary theory, such as symbiogenesis, evolutionary understanding has since then become a cornerstone of my spirituality.
As an artist and musician, I also appreciate the 'creativity' embedded in the process of evolution. Evolution says "give it a try". If it doesn't work, it tries something new. Once in a while, something sticks; it survives its own context some way or another. Other forms die out, like snapshots of some greater metamorphosis. We are lucky to witness them!
However, I might not be getting your point.
> However, I might not be getting your point.
If you weren't, it wasn't your fault, it's more because I was being a little too tacit.
The reason for my comment was to point out a remarkable similarity between two spiritual/philosophical frameworks that have been painted as diametrically opposed, and whose adherents are often cast as irreconcilable enemies. I grew up with both of these influences each in their own strong ways, and struggled to integrate them within myself. I'm grateful that I've been able to at all. Some people end up feeling spit out and bitter.
My point is that the Hebrew word for god is essentially "I am cause I can be". Which is pretty close to "it is what it is". It's a very existential kind of character, but pretty simple. It's kinda like that question recently posted on hacker news, why does anything exist? The answer here being "because it can, that's why".
I'm not advocating that you or anyone adopt my spiritual worldview, just sharing my perspective. Actually, my journey has been to let go of the baggage of institutionalized Christianity. But I've chosen not to 'throw the baby out with the bathwater'. I still believe that traditional myths and stories, including my own, are beautiful and interesting.
As far as the article goes, I actually take issue with the presented dichotomy between "function" and "no function", because to me, every DNA sequence/expression, or lack-thereof, has some implication, however nuanced. Whether or not that implication counts as "functional" or not is often beyond the capabilities of our time machines and is philosophically up for discussion. As far as evolution is concerned, and here's where I agree with the article, whether or not something counts as "functional" is beside the point. The point is that if something survived, it did so because nothing was stopping it. Or as you say because "it just happened that way", kinda like those "extra" notes in a jazz solo.
https://en.wikipedia.org/wiki/Jordan_Peterson https://www.youtube.com/user/JordanPetersonVideos http://jordanbpeterson.com/2016/12/podcast/
Let me explain: evolution is a massive, groping search in the ultrahigh dimensional space of possible organisms, one that is solving for fitness by literally obliterating less fit entities from existence. So fitness is actually just "what is good at existing", which, given enough iterations, will determine what actually exists anyway.
So now we can simply substitute in the answer to the question "why do we exist?": We exist because we evolved, which is like saying, we exist because we are fit, which is like saying, we exist because we exist. And that explanational ouroboros sort of levitates before us, a silent, immutable feature of the universe: we are here because we exist, because we exist, because...
And it's so easy for us to make that small, seductive step to saying that our existence is therefore inevitable. But I think that's a mistake. The tautology doesn't answer the why question; it annihilates it, dissolving the teleological question into its mechanistic refutation: WE. ARE. HERE.
It's not a search. There is no goal, no searcher, and nothing to find. The word evolution was chosen deliberately in its meaning of a dynamical system moving through state space. Not searching: just evolving.
Evolution only makes sense if we think of it as as some kind of massively parallel Monte Carlo that's weighted to explore regions of the state space with high fitness. So it's perfectly valid to talk, as biologist do, of selection pressures and directional selection, because- and here we've come full circle- there is a goal to evolution: to exist.
Kind of like the space program, where everything is made by the lowest bidder.
Could you elaborate on why you see that as reflecting evolution? To me, being consistent with past and future means stasis and would preclude the evolution of such diverse lifeforms as we see today.
$living_thing with $property (wing coloration) is dead before reproduction happens, $property may not be transmitted to the offsprings.
It's a simple enough concept at its core. Then comes the complications of mutations, random this and that.
what is your evidence for this claim?
when you say "how can we account for butterflies that mimic wing coloration Of toxic counterparts to ward off birds" there's no reason to suppose the development of that would need to be directed.
This is news?
And I claim precedence on the phrase "just so story" for those things biologists have been spouting for decades.
The article does give the background here - there are multiple positions within evolutionary biology. All accept natural selection, of course, but the fine details matter too. In particular here the question is a decades long debate that Gould&Lewontin headed, saying that not all apparently-useful adaptations evolved, some are "spandrels" that arose for other reasons.
The article mentions other reasons to suspect that things that seem useful did not evolve, such as the surprising effect of drift in multicellular organisms (us) vs single-celled organisms. In the latter, selection affects each nucleotide of DNA. In the former, selection must be powerful enough to overcome noise, otherwise it is ineffective - which seems surprising, as this is averaged over many individuals over much time. The surprising thing is that this effect is, it turns out, non-linear.
Junk DNA is real, although it also serves as a broad canvas on which selection can subsequently act. Pervasive transcription doesn't mean pervasive genomic adaptation.
A significant number (perhaps even a majority) of biologists seem to hold views akin to a naive adaptationist outlook, which demonstrably leads them astray in their interpretation of data. The proportion of the educated public holding these views is even higher. Richard Dawkins has a lot to answer for.
Above all, a simplistic adaptationist view of evolution is not only inaccurate, ignoring the last half-century of developments in the field of population genetics, but also misses a lot of the (often subtle) detail that makes evolutionary biology so interesting.
The idea is basically that junk DNA contains a memory in shape of a distributed representation of the past of the organism and its environment, akin to how neural networks encode information. It basically provides a basis for fast adaptability by introducing noise into the gene expression and morphogenesis process so as to have more versatility and robustness to explore alternatives (very similar to dropout in neural networks).
90% of our genome is unconserved, meaning that it is not under selection. Most of this consists of dead viruses and mobile elements. Such DNA was present for its own purposes while it was active but is long since dead. A tiny proportion of this junk is later co-opted by the host organism.
The null hypothesis is that junk DNA is junk. It survives in the genomes of species with small effective population size because its selection coefficient is too small for it to be purged.
The alternative hypothesis you gave would need evidence to support it, otherwise it's another 'just so' story. Ask yourself, if this junk is beneficial for adaptation as you hypothesize, why don't bacteria have any? More broadly, why is the amount of junk DNA indirectly proportional to the effective population size (as the null hypothesis predicts)?
Based on what you've done here there is a some unnecessary.