Comment author: Kaj_Sotala 26 February 2016 05:16:59PM *  3 points [-]

Evolution in humans seems to have stopped.

The 10,000 Year Explosion disagrees; to quote my own earlier summary of it:

60,000 years ago, there were something like a quarter of a million modern humans. 3,000 years ago, thanks to the higher food yields allowed by agriculture, there were 60 million humans. A larger population means there's more genetic variance: mutations that had previously occurred every 10,000 years or so were now showing up every 400 years. The changed living conditions also began to select for different genes. A "gene sweep" is a process where beneficial alleles increase in frequency, "sweeping through" the population until everyone has them. Hundreds of these are still ongoing today. For European and Chinese samples, the sweeps' rate of origination peaked at about 5,000 years ago and at 8,500 years ago for one African sample. While the full functions of these alleles are still not known, it is known that most involve changes in metabolism and digestion, defenses against infectious disease, reproduction, DNA repair, or in the central nervous system.

The development of agriculture led, among other things, to a different mix of foods, frequently less healthy than the one enjoyed by hunter-gatherers. For instance, vitamin D was poorly available in the new diet. However, it is also created by ultraviolet radiation from the sun interacting with our skin. After the development of agriculture, several new mutations showed up that led to people in the areas more distant from the equator having lighter skins. There is also evidence of genes that reduce the negative effects associated with e.g. carbohydrates and alcohol. Today, people descending from populations that haven't farmed as long, like Australian Aborigines and many Amerindians, have a distinctive track record of health problems when exposed to Western diets. DNA retrieved from skeletons indicates that 7,000 to 8,000 years ago, no-one in central and northern Europe had the gene for lactose tolerance. 3,000 years, about 25 percent of people in central Europe had it. Today, about 80 percent of the central and northern European population carries the gene. [...]

People in certain areas have more mutations giving them a resistance to malaria than people in others. The human skeleton has become more lightly built, more so in some populations. Skull volume has decreased apparently in all populations: in Europeans it is down 10 percent from the hight point about 20,000 years ago. For some reason, Europeans also have a lot of variety in eye and hair color, whereas most of the rest of the world has dark eyes and dark hair, implying some Europe-specific selective pressure that happened to also affect those.

As for cognitive changes: there are new versions of neurotransmitter receptors and transporters. Several of the alleles have effects on serotonin. There are new, mostly regional, versions of genes that affect brain development: axon growth, synapse formation, formation of the layers of the cerebral cortex, and overall brain growth. Evidence from genes affecting both brain development and muscular strength, as well as our knowledge of the fact that humans in 100,000 BC had stronger muscles than we do have today, suggests that we may have traded off muscle strength for higher intelligence. There are also new versions of genes affecting the inner ear, implying that our hearing may still be adapting to the development of language - or that specific human populations might even be adapting to characteristics of their local languages or language families.

Comment author: efalken 29 February 2016 12:45:32AM 1 point [-]

Allele variation that generates different heights or melanin within various races, point mutations like sickle cell, the mutations that generate lactose tolerance in adults, or that affect our ability to process alcohol, are micro-evolution. They do not extrapolate to new tissues and proteins that define different species. I accept that polar bears descended from a brown bear, that the short-limb, heat-conserving body of an Eskimo was the result of the standard evolutionary scenario. I have no reason to doubt the Earth existed for billions of years.

Humans have hundreds of orphan genes unique among mammals. To say this is just an extension of micro-evolution relies on the possibility it could happen, but you need 50MM new nucleotides that work to arise within 500k generations. Genetic drift could generate that many mutations, but the chance these would be functional assumes proteins are extremely promiscuous. When you look at what it takes to make a functioning protein within the state-space of all amino acid sequences, and how proteins work in concert with promoter genes, RNA editing, and connecting to other proteins, the probability this happened via mutation and selection is like a monkey typing a couple pages of Shakespeare: possible, but not probable.

This all argues for a Creator, who could be an alien, or an adolescent Sim City programmer in a different dimension, or a really smart and powerful guy that looks like Charlton Heston. The argument for a Christian God relies on issues outside of argument by design

Comment author: ChristianKl 23 February 2016 05:59:07PM *  2 points [-]

Any present version of a protein that evolved >1,000,000,000 years ago is only homologous and not identical to it's predecessor.

just would take too long

A billion years does happen to be really long, especially if you have very many tiny spots of life all around the planets that evolve on their own.

What works in a lab in a few years is radically different than what works in billions of billions of parallel experiments done for billions of years.

Pointing out homologs still leaves the problem of tranversing a highly spiked fitness landscape, but if this is ever demonstrated on say, a new protein complex in E. coli, I'd say, you win

How do you judge something to be a new protein complex? Bacteria's pass their plasmides around.

E.coli likely hasn't good radically new protein complexes in the last millions of years so anything it does presently is highly optimized and proteins are only homologous to their original functions.

I think you are more likely to find new things in bacteria's that actually adept to radically new enviroments.

Comment author: efalken 24 February 2016 01:21:57AM 3 points [-]

The years thing seems to make everything probable, because we have basically 600 MM years of evolution from something simple to everything today, and that's a lot of time. But it is not infinite. When we look at what evolution actually accomplishes in 10k generations, it is basically a handful of point mutations, frameshifts, and transpositions. Consider humans have 50MM new functioning nucleotides developed over 6 million years from our 'common ape' ancestor: where are the new unique functioning nucleotides (say, 1000) in the various human haplogroups? Evolution in humans seems to have stopped. Dawkins has said given enough time 'anything' can happen. True, but in finite time a lot less happens.

They've been looking at E. coli for 64000k+ generations. That's where we should see something, and instead all we get is turning a gene that is sometimes on, to always on (citT), via a mutation that put it near a different promoter gene. That's kinda cool, and I admit there's some evolution, but it seems to have limits.

But, thanks for the respectful tone. I think it's important to remember that people who disagree with you can be neither stupid or disingenuous (there's a flaw in the Milgrom-Stokey no-trade theorem, and I think it's related to the 'Fact-Free Learning' paper of Aragones et al.)

Comment author: ChristianKl 23 February 2016 05:06:28PM 3 points [-]

eg, certain things, like anti-freeze in fish, are evolutionarily possible, others, like creating a flagellum, are not

The evolution of the flagellum works because proteins used in it are useful in other context:

The best studied flagellum, of the E. coli bacterium, contains around 40 different kinds of proteins. Only 23 of these proteins, however, are common to all the other bacterial flagella studied so far. Either a “designer” created thousands of variants on the flagellum or, contrary to creationist claims, it is possible to make considerable changes to the machinery without mucking it up.

What’s more, of these 23 proteins, it turns out that just two are unique to flagella. The others all closely resemble proteins that carry out other functions in the cell. This means that the vast majority of the components needed to make a flagellum might already have been present in bacteria before this structure appeared.

Comment author: efalken 23 February 2016 05:32:47PM 2 points [-]

Of the millions of proteins on the planet it is unremarkable most exist elsewhere, just as it's likely most parts in a car can be found in other machines. Further, these aren't identical proteins, merely 'homologous' ones, where there's a stretch of, say, a 70% match over 40% of the protein, so that makes this finding not surprising (lug nut in engine A like fastener in engine B). A Type 3 Secretory System has about 1/3 of the proteins in a flagellum (depends which T3SS, which flagellum), but to get from one to the other needs probably ten thousand new nucleotides in a specific constellation, and nothing close to that kind of change has been observed in the lab w/ fruit flies or E. coli. So, it's possible, but still improbable, like turning one of my programs into another via random change and selection, there are many similarities in all my programs, but it just would take too long. Possible is not probable, and unlike cosmological improbabilities, there's no anthropic principle to save this. Pointing out homologs still leaves the problem of tranversing a highly spiked fitness landscape, but if this is ever demonstrated on say, a new protein complex in E. coli, I'd say, you win (but more complex than moving a gene closer to a promoter region as in the citT).

Comment author: Viliam 23 February 2016 08:58:43AM 5 points [-]

Here is a shortened version:

Darwin’s grandfather believed in something similar to abiogenesis. Later in Darwin’s life, scientists found something that appeared to be the first proto-cell, but later they found a progenitor to this in oceanic mud. Darwin believed that the discovery of the first life form would occur soon, but it didn't happen. Organisms that reproduce, metabolize energy, and create a cell wall, require at least a hundred proteins, each of which has approximately 300 amino acids, and all need to be able to work with each other.

To reach this level of sophistication via chemical evolution defies explanation. The experiments in 1953 created some of the amino acids found in all life forms, but this is a far cry from creating proteins. The origin of life is one of those puzzles that has been right around the corner, for the past two centuries. Imagining something is not a scientific argument, but simply speculation. Many present all evolution as similar to how wolves changed to sheepdogs, or the way in which bacteria develop resistance to penicillin, but such change will not create radically new protein complexes or new species.

If evolution is untrue, it changes everything. After I accepted that a creator exists, I found myself attending church, engaging in Bible study, and reading Christian authors. Various facts all began to make much more sense.

Comment author: efalken 23 February 2016 03:33:19PM 7 points [-]

I'm a big Eliezer fan, and like reading this blog on occasion. I consider myself rational, Dunning-Kruger effect notwithstanding (ie, I'm too dumb or biased to know I'm not dumb or biased, trapped!). In any case, I think the above is pretty good, but I would stress the ID portion of my paper, which is in the PDF not the post, is that the evolutionary mechanism as observed empirically scales O(2^n), not O(n), generally, where n is the number of mutations needed to create a new function. Someday we may see evolution that scales, at which point I will change my mind, but thus far, I think Behe is correct in his 'edge of evolution' argument (eg, certain things, like anti-freeze in fish, are evolutionarily possible, others, like creating a flagellum, are not). As per the Christianity part, the emphasis on the will over reason gives a sustainable, evolutionarily stable 'why' to habits of character and thought that are salubrious, stoicism with real inspiration. Christianity also is the foundation for individualism and bourgeois morality that has generated flourishing societies, so, it works personally and for society.

My younger self disagreed with my current self, so I can empathize and respect those why find my reasoning unconvincing, but I don't think it's useful in figuring things out to simply attribute my belief to bias or insecurity.

Comment author: efalken 19 June 2014 09:51:12PM 3 points [-]

Ever notice sci-fi/fantasy books written by young people have not just little humor, but absolutely zero humor (eg, Divergent, Eragon)?