I say no but why do evolutionists?
This is a sly way to demonstrate how unlikely evolutionism is on a probability curve.when on thinks of the millions (billions?) of segregated populations in biology(species) then it should be a high, or respectable percentage, are evolving as we speak to create new populations with new bodyplans to survive in some niche. By high I mean millions, with a allowance for mere hundreds of thousands. YET I am confident there is none evolving today. further i suspect evolutionists would say there is none evolving today. WHY? If not today what about yesterday or 300 years ago? Why couldn’t creationists say its not happening today because it never happened? Its accurate sampling of todays non evolution for predicting none in the past!
i think the only hope (hope?) is if evolutionism said , under pE influence, that all biology today is in the stasis stage and just waiting for a sudden need to change, qickly done, then stasis again. Yet why would it be that stasis has been reached so perfectly today relative to the enormous claim of the need in the past for evolutionism?
Anyways i think creationists have a good point here but willing to be corrected.
Okay, so you don’t appreciate my jokes 🙁
Not that I am aware of. Could you name one example?
Good, let’s return to transposable elements. They are “selfish” genomic parasites, right?
JMac fails to recognize statements without !!!!lol!!!smiley!! as humorous.
How different is a one-week old human baby from a one-week old chimpanzee baby?
How much of the difference at 1 year, 10 years and 25 years is due to genes, and how much is due to the human absorbing the collective fruits of thousands of years of human development?
You might want to check up on feral children to get a feel for this.
What else is left when someone spends a large chunk of his career trying turn Drosophila into something else, fails miserably, and yet believes sheer dumb luck would have done better?
Do you see my point? Nuh, eh?
You. You’re good, you!!! (No emoji allowed sry…)
Quite so — I mean, I think that these are the right questions.
However, my understanding is that none of the literature on feral children is useful. There are anecdotes and stories that aren’t well confirmed, and the most extensively studied “feral child” — Genie — could have suffered from abuse, neglect, mental disability — plus (I very vaguely recall) there were questions about the research ethics of those who studied her. Between confounding variables and questionable methods, it’s a real mess!
Can you also say nice things? I don’t think I have seen a single comment from you that wasn’t an insult or a childish taunt since you returned.
I reckon you are right about that, but it is still interesting to note that as far as we can tell feral children appear to develop behaviour and traits much more akin to the animals in whose company they grow up, than akin to other humans. It would appear that individual humans generally do not have innate capabilities that are all that far removed from those of other primates, and that the lofty intellectual and artistic achievements of human culture are very much a result of aggregating millions of tiny steps over time.
Someone said it: I stand on the shoulders of giants. In fact it is giants all the way down 🙂
I can also imagine that which went before existing as a process which is aiming at a specific future state. Eyeballs are a good example. The developing eyes of the foetus are forming and being positioned so as to allow for the binocular vision yet to come. The future is determining the path of that which went before.
Supersensible, not mystical. In the same way that light is supersensible, vacuum energy is supersensible, gaseous oxygen is supersensible. There is nothing mystical about these entities.
If we think of the archetype as the source of all possible living forms, then all living forms are limited expressions of the archetypal form. (Our language is designed to communicate within our dimensions of space and time experienced through the senses and so my use of the word “source” conjures up a point in space. And so to avoid misunderstanding, by source I mean something that encompasses and pervades all of space from the infinitely concentrated point to the infinitely extended plane). We cannot judge its presence or absence on the grounds that we cannot perceive it with any of our five physical senses.
Its effects are there for us to see. See the article Ancestor of the new archetypal biology: Goethe’s dynamic typology as a model for contemporary evolutionary developmental biology by Mark F. Riegner for a more complete discussion about this with various examples to consider.
The abundance of convergent evolution such as the shared developmental pathway of the different eye types of a wide variety of animals is better explained by the archetype model than speculations about the retention of an ancient plan.
Why would I be trying to educate you on biology? I’m sure that it is not just you reading these posts. My aim is not to educate but to perhaps stir the interest of those who haven’t previously had the inclination to look at the latest research on cellular processes. With all the information now generally available it has never been easier for individuals to educate themselves.
What is your best example or examples of nucleic acids performing work?
Venter could not have succeeded without using protein complexes to manipulate his “synthetic” chromosome. He would have used vectors and I know he needed to make epigenetic alterations to the DNA he was using. In order for the cell to remain viable the DNA had to have very precise external manipulation. It could be said that as Venters team used the DNA available to them, in like manner the cell then used the genes that were available to it.
Yes, there would have needed to be intricate directed processes in operation right from the beginning of cellular life.
Here is an interesting piece of information. They write:
Only those who were overconfident in their knowledge would be surprised by this lack of knowledge. It is always a case of, “more complex than we thought”. To be totally surprised and shocked by this reveals a preconception that life at its most basic level is simple. Who would think such a thing?
I can still remember my first encounter with fly agaric. It was in the days when a nine or ten year old boy could wander about in the countryside without being tethered to an adult. I saw it by the side of a path and I can still remember my feeling of joy and admiration for nature.
And speaking of insect legs, here is another interesting finding:
Another example of natural ingenuity preempting human engineering. But producing individual creatures that have attained self-consciousness requires ingenuity of a whole new level.
But these processes all require the DNA to be acted upon by the protein complexes of the cell. There is no activity without this. Regarding these complex processes there is no simple extrapolation of cause and effect.
There are levels of autonomy. Rocks and pebbles have no autonomy discernible, they can only be seen to change and move by being acted upon by external forces. Prokayotes can move because of internal forces, giving them a level of autonomy that rocks don’t have. Humans can move about with relative freedom, we can consciously change and adapt our local environment as it suits us. Think of food production. We don’t just forage about looking for food, we actively produce and distribute food. It is through such activities that we become more autonomous than the rest of life around us.
As I see it, rock have complete autonomy. They can do whatever they want to do — which is nothing at all.
Maybe the word you are looking for is “agency” (rather than “autonomy”).
Certainly. None of my contentions are absolutes. Little in biology is.
Heh. No, it might be clearer to forget that these are virtually indistinguishable and recognise that they are actually separate species. If we had a series of contests between a varied and numerous resident and an incomer species that had minimal variation, trying to garner the same resources by doing the same thing over and over, would we really expect the second species to replace the first, generally?
They can’t compete with things that aren’t there! What else could explain the tendency of asexuals to be found in extreme environments, if not the difficulty of competition where sexuals are well-established?
It can be transmitted reliably enough. Epistasis effectively gives a boost to the selection coefficients of both alleles in the relationship – in the genetic background that includes the other, there is a higher s for each than in those backgrounds that don’t. This elevates the frequencies of both halves of the epistatic relationship, and so recombination generates the pairing more frequently. It was recombination that got them together in the first place, so it wasn’t a detriment then. Typically, once formed, a pairing on the same chromosome should last a few generations. And even where broken, it just means those instances have a reduction in fitness for that epistatic interaction. Who knows about the rest of the genome? Simple models ignore it. It’s the net result that determines if recombination is ‘costly’. Breakage of specific epistasis selects for closer linkage, not (necessarily) abandonment of all recombination.
Yes, this is getting to the heart of things. I’m not arguing for a driver of recombination, but a reason why asexuals don’t pose the threat to sexual populations that is commonly portrayed. I don’t think recombination is at the heart of sex. I think it’s a byproduct, and is unavoidable, even without crossover.
Again, I’m not being absolutist. But I think the standard expectation is that asexuals ‘should’ win most contests, absent a compensatory benefit (still being sought). I think sexuals will win far more often than is generally supposed, but the simpler the model, the less clear this is.
I probably need to finish off my revised post on this; my points might become clearer.
Well, I’ve no idea how your mum and dad met, but probably not! 🤣
Here we go round the mulberry bush. Those proteins are made from genes, held in DNA. Yes, the genes are made into proteins by other proteins, but they too are made from DNA genes. DNA is at the heart of it.
And, you are continuing to confuse evolutionary logic with physiological detail. All that persists through evolutionary time is genetic sequence. [Charlie: “but that genetic sequence is an abstraction, it has no meaning until acted on by proteins …”].
I’ve thought a bit more about this; it goes back to my point about ‘tenure’. Invariably, diploid asexuals arise in an environment already colonised by sexuals. Even if all else were equal (it isn’t), one would expect the species with the greater numbers to persist most of the time. It’s the same as drift – in a population of 10,000, a new neutral allele will be lost 9,999 times on average for 1 fixation.
But asexuals can go beyond the bounds of the range because they are not restricted by the need for mates. Once established, the above situation is reversed. Incursions by the sexual are still limited by mates, plus the ‘tenure effect’. The variation of the wider population is no help in this reverse competition, where they are in the minority.
This would tend to restrict asexual populations to ‘satellite zones’.
That’s weird because that’s not what it says in what you quote.
That isn’t life at it’s most simple level. Those are cells able to fully power their own metabolism and replication, that live freely in solution or on agar.
A fluctuating temperature can accomplish what living cells now employ enzymes to do: separate and annealing of double strands of DNA and RNA(a fact deliberately exploited in PCR).
Cells today now use enzymes to biosynthesize their own components, but it is possible there are geochemical analogoues of those biosynthetic pathways that could do it for them(for example it has been shown that nothing more than iron cat catalyze most of the reverse kreb’s cycle). Cells today use protein channels and transporters of various types to transport components across the otherwise impermeable phospholipid membrane, of which there are simpler physical mechanisms that can accomplish with semipermeable fatty acid membranes. And so on and so forth. There is considerable both experimental and phylogenetic evidence for stages of life that were simpler than any currently known wild-type or synthetic cell.
Heck, there is even evidence that the earliest proteins were synthesized from amino acids produced by the abiotic chemical reactions happening in the environment, as opposed to those being synthesized by evolved metabolic pathways inside cells. As we go further back on the tree of life, the frequency distribution of amino acids in universally conserved proteins increasingly mirrors the same types of frequency distributions of amino acids produced in things like spark-discharge and hydrothermal chemistry experiments, and observed in meteorites like carbonaceous chondrites. This is evidence right there for the putative source of the amino acids that made up the very first proteins to evolve around the origin of life.
Cause and effect of what? Is this your “the cell drives it’s own evolution” holistic nonsense again? We’ve been over that. It doesn’t.
There is also the evidence fromMiller’s dry ice/acetone experiment that he ran for over 25 years. From an initial spiking of amonnia and cyanide he found 11 different nucleases and seven different amino acids. Eutectic chemistry is quite interesting and experiments have demonstrated RNA elongation of 400-700 mucleobases and RNA enzymes running in reverse, e.g., ligating RNA instead of cutting it. It is an interesting field of research which has demonstrated the concentration of reactants in eutectic phases and robust production of molecules essential for life as we know it today.
Here is a nice article that summarizes the research:
Did Life Evolve in Ice?
Not generally, but we do if they operate in a context where the asexual can take advantage of its superior colonization ability, or if it happens to escape severe costs of sexual reproduction (e.g. very strong sexual conflict).
But why aren’t they there? You don’t expect unoccupied habitats when the population is at carrying capacity.
I need to look this up*, but as I recall asexual populations are not confined to crappy leftover corners. They typically have larger ranges, at higher latitudes (geographic parthenogenesis).
*(Damn, we need more ecologists here at the site)
Let’s ignore epistasis and focus on what I view as the main problem of recombination: dispersion of adaptive alleles. As you have correctly observed, recombination predominantly generates genotypes that result from combining high frequency alleles. Ideally, the most fit multilocus genotypes will become more and more common as the frequency of beneficial alleles rises to fixation.
The problem for sexual populations in a meta-population is that the allele frequency will settle at migration-selection equilibrium (migration is an evolutionary force that acts similar to recurrent mutation). The more unlinked loci that affect local adaptation, the more rare the most fit multilocus genotypes are. Let’s say that local adaptation is determined by the genotype at = 10 unlinked loci, and that the most fit genotype occurs at = 0.8 at every locus. Then we still only see the most fit multilocus genotype in a meagre 11% of the sexual population. If a parthenogenic lineage starts from within that 11% it is going to be dynamite, because it isn’t bothered by the inconvenient ongoing recombination with maladaptive migrant genomes.
That’s why I refrained from mentioning the cost of males. Sex has several other issues.
Absolutely, looking forward to that.
Such as aphids, yes (although most aphids are not strictly asexual species – they simply extend the mitotic line through a few multicellular bodies).
Sure. Contingent, though. The ‘mystery of sex’ ™ is portrayed in quite general terms.
There is a density dependence issue with obligate outcrossers. An asexual evades this, either in the inevitable within-range granularity of distribution or at the edges of a current range. I think there’s a tendency with population-genetic thinking to over-homogenise.
OK, but this was a critique of your friend’s claim that the geographic model was ‘neutral’. I can’t see a reason for squeezing them into habitats where they suffer elevated extinction unless something is ‘pushing’ them there.
If rare, how confident can we be that any random haploid pairing, frozen in perpetual diploidy, has it? It can only be average, on average!
Certainly, if the asexual happens to have the fittest multilocus genotype, it will be better than the rest, but only until the sexuals respond to selection. They are chucking prospective combinations at the wall continually, and importing beneficial loci; eventually a rare pairing or incomer will hit the jackpot. Having been formed, any new combination will be severed in a proportion of meioses, but it depends on linkage distance as to how often. Even on different chromosomes they’ll stay paired 50% of the time, giving a corresponding boost in the same proportion. As they become commoner, that 50% goes up, as the proportion of swaps making no difference increases.
Asexuals always play ‘stick’, whereas the best strategy, ISTM, is ‘twist’.
Gradually, the sexual would start pulling away, thanks to recombination and migration, not despite them.
First, I’ll juxtapose those:
I think your own answer is correct. Obligate outcrossers cannot thrive in those habitats because of the allee effect.
My intuition tells me that the asexual just needs to have above the sexual average fitness to persist. I also note that asexuals tend to be more generalist than their sexual sister species, so the average is what we are getting most of the time, it seems.
You will have to excuse me for not accepting your verbal argument. Because of mutation, novel beneficial combinations will pop up in the asexual population as well, and those can spread more quickly, as they won’t be destroyed by recombination. I suspect the outcome critically depends on details of respective population sizes, mutation rate, migration rate, extinction rate of local populations and the genetic architecture of local adaptation. That’s way too complicated to assess without mathematical modeling.
I have made a similar comparison to this in the past. If we compare a single bacterium to one cell then groups of bacteria can be seen as equivalent to a multi-cellular organism.
And it’s interesting that you see and accept that, as in the case of the chemostat, an overall balance is maintained while there is change and turnover at a lower level. But when I point out the equivalence at higher levels, you cannot agree. For example, say, reptile species: turnover has been taking place at this level within the more enduring higher class of reptilia.
These processes involve so many intricate, directed coordinated activities. Ensuring the chromosomes are moved precisely into position. The correct positioning and tension of the spindle fibres must be achieved by the constant addition and subtraction of tubulin. Only then can the chromosomes be pulled to the poles. And this is just one small part of the process of meiosis.
Fascinating, thanks for the link.
You might like/appreciate this article as well:
Published: 21 September 2010
Ice as a protocellular medium for RNA replication
James Attwater, Aniela Wochner, Vitor B. Pinheiro, Alan Coulson & Philipp Holliger
Nature Communications volume 1, Article number: 76 (2010)
I don’t mind which word we use as long as it is understood that I’m talking about levels of inner freedom.
The reflexive universe: Evolution of Consciousness. Anodos Foundation. Kindle Edition. by Arthur M Young
IMO we can no longer speak about objects in time and space as though these are separate entities. If we want to think in accord with reality then everything is process.
A rock is not doing “nothing at all”, it is moving relative to the celestial objects around it. But this movement it has is not of its own accord. It is not free to change course out of any inner volition.
To achieve this partial sequence matching chromosomes must move or be moved. Do you know how this is achieved? Also do you know how the spindle microtubules correctly assemble and align to join the kinetochore with the centrosome?
I don’t see how any form of cell replication can be seen as primitive. Primitive implies crude. Maybe simpler but not primitive. What evidence is there that it was primitive?
The initial growth of physical life would have had its own challenges other than competition.
That’s basically behaviorism, as an alternative to materialism/physicalism. I tend to see myself as a behaviorist.
That’s probably not quite right. However, what makes something an object is mostly human decisions. The world does not dictate what should count as an object.
No, the rock is doing nothing. Whether we see it as moving is a matter of what we count as motion.
No I believe it because of what has been written and said about it. Just a very quick search and I found the following and there are plenty more there for anyone to see. .And that is just with reference to scientists. When I said “many people” I was referring to people in general.
From a description of the book Junk DNA: A Journey Through the Dark Matter of the Genome by NessaCarey
Different behaviour maybe in some respects. But orbiting, spiralling motion is a feature of all levels of resolution.
Oh, you meant some confused pop-sci writers. OK, who cares?
The thing is the thrust of your comment when you say “But as our knowledge increased this was found to be false.” seems to be that they were justified in believing that based on the scientific consensus at the time, which is not true for all I know. I’ll let the local biologists take over because I’m not qualified to discuss the topic at hand
No, it is not. Electrons belong to the realm of *lowers voice to whisper* quantum mechanics. Their behaviour is radically different from macroscopic objects. Most notably, and most damning to your claim, they exhibit wave-particle duality. Planets don’t do that (thank heavens).
I recommend you read the review of that book by our favorite curmudgeon Larry Moran, if only for amusement value.
ETA: Not a complete review I note, just the free introductory pages.
Analogies, analogies everywhere,
And all the minds did think;
Analogies, analogies everywhere,
Not one could see the link.
Hats off to Coleridge. I’ve always loved that poem.
Don’t worry! I never let that hold me back.
Well, if Eric can pretend to be a physicist and philosopher at MindMatters and make money for talking nonsense, I guess I can do the same thing here for free 🤣