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Forearm artery reveals human evolution continues?

news.flinders.edu.au

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Re: Forearm artery reveals human evolution continues?

#71

Post by SamReidHughes »

iheartblocks wrote: post #2

This seems rather dubious to me; what selection pressure exists that's increasing fitness for people with three arteries? The fact that it's progressing so rapidly suggests that this is either bad data, or environmental changes

Let's assume the research is sound. (Inferring from mci's comment, probably not.) But let's suppose we saw this phenomenon in a specific country's population, measured without any sampling bias. It could be from:

- selection pressure for some other trait that happens to involve some genetic material that affects the forearm arteries.

- the recent removal of strong selection pressure for having two arteries, on a trait that generally tends to drift towards three arteries in many directions.

- a dominant gene isolated to one province, which then got diluted across the population when people traveled more.

- a trait found more often in the rural population, which over the past century had more children.

Re: Forearm artery reveals human evolution continues?

#72

Post by pfdietz »

ip26 wrote: post #68
pfdietz wrote: post #39

Earlier quoted context omitted.

With no selection pressure a gene will not from 10% to 30% in a few generations. That requires a tremendous selective advantage.

Well, or it just needs to be a dominant gene.

That makes absolutely no difference.

Re: Forearm artery reveals human evolution continues?

#73

Post by jessaustin »

ip26 wrote: post #68
pfdietz wrote: post #39

Earlier quoted context omitted.

With no selection pressure a gene will not from 10% to 30% in a few generations. That requires a tremendous selective advantage.

Well, or it just needs to be a dominant gene.

The gene didn't become dominant in the last several generations.

Re: Forearm artery reveals human evolution continues?

#74

Post by danieltillett »

sokoloff wrote: post #60
danieltillett wrote: post #49

Earlier quoted context omitted.

This problem has been solved long ago. Screen all grant applications to weed out the flawed approaches (the bottom 25%) and then run a lottery on the remaining. If there is nothing to game, the gaming stops.

Why wouldn’t the gaming morph to stuffing the lottery? Submit similar grants with different PIs, different combinations of researchers, slightly different focuses or plans.

You can limit how many grants people are allowed to put in. This already exists with the current broken system.

Re: Forearm artery reveals human evolution continues?

#75

Post by jessaustin »

sradman wrote: post #45
rthomas6 wrote: post #24

Could this be an epigenetic/gene expression change caused by increased use of our forearm and hand muscles? For instance, how I'm typing this right now, and how children write a lot more than they used to.

From the paper's Introduction: > The regression of the median artery commences at approximately the eighth week of intrauterine life. However, the median artery persists in a considerable number of foetuses of gestation ages 13–38 weeks, in newborns and infants and in adults. I'm guessing no to epigenetics unless it involves a change in the intrauterine environment.

Changes to the intrauterine environment (which is affected by the larger environment that has seen significant changes) are vastly more likely than selection pressure of the strength proposed in TFA.

More likely yet is that this is a spurious interpretation of bad data. The anatomists of centuries past weren't looking at the median arteries of all humans.

Re: Forearm artery reveals human evolution continues?

#76

Post by danieltillett »

dwohnitmok wrote: post #62
danieltillett wrote: post #49

Earlier quoted context omitted.

This problem has been solved long ago. Screen all grant applications to weed out the flawed approaches (the bottom 25%) and then run a lottery on the remaining. If there is nothing to game, the gaming stops.

Apart from the issue of grant stuffing, I have a strong suspicion that 25% is an extremely low number and even among those grant applications that pass obvious flaws there is still an extremely large variance in quality. To put it another way, imagine if a strategy for funding software development was to take every piece of software that compiled and then randomly choose among them to fund. This seems like it's ripe…

Having personally read through a large number of grant applications I would say 25% is about accurate. It really doesn’t change anything if we were to raise the threshold to say the top 50%. The key to success is to remove the human element of trying to determine what is a top 5% grant from a top 10% grant. This has been proven to be impossible.

You can stop the grant stuffing gaming by limiting the number of grants people can apply for every year.

Re: Forearm artery reveals human evolution continues?

#77

Post by danieltillett »

bonoboTP wrote: post #51
danieltillett wrote: post #49

Earlier quoted context omitted.

This problem has been solved long ago. Screen all grant applications to weed out the flawed approaches (the bottom 25%) and then run a lottery on the remaining. If there is nothing to game, the gaming stops.

But it goes way deeper than just grants. Who will get tenure for example? Citations and publication counts are used for many many things. Also, making your findings sexy is not just done to improve metrics for promotion and grants. Sexy research also draws attention among experts and lay media alike. They will be invited to give talks at conferences and seminars etc. more if their findings are exciting.

The same approach can be applied to tenure. Set a basic threshold that someone needs to meet, then run a lottery to chose who gets tenure. Would end an amazing amount of unproductive gaming of the system.

Re: Forearm artery reveals human evolution continues?

#78

Post by evandijk70 »

danieltillett wrote: post #76
dwohnitmok wrote: post #62

Earlier quoted context omitted.

Apart from the issue of grant stuffing, I have a strong suspicion that 25% is an extremely low number and even among those grant applications that pass obvious flaws there is still an extremely large variance in quality. To put it another way, imagine if a strategy for funding software development was to take every piece of software that compiled and then randomly choose among them to fund. This seems like it's ripe…

Having personally read through a large number of grant applications I would say 25% is about accurate. It really doesn’t change anything if we were to raise the threshold to say the top 50%. The key to success is to remove the human element of trying to determine what is a top 5% grant from a top 10% grant. This has been proven to be impossible. You can stop the grant stuffing gaming by limiting the number of grants…

Don't forget that the people writing the grants are heavily influenced by what is required to obtain a grant. If the aim of writing a grant becomes to not be in the bottom 25%, than the average quality of grants will go down.

I think it has not been proven to be impossible to determine the difference between a top 5% and a top 10% grant, it has just been proven that the current system does not do that. In trainings for grant applications it is often mentioned that members of grant committees spend extremely little time per grant proposal, which I imagine is just sufficient to weed out the bottom 25% proposals (those that contain obvious flaws)

Re: Forearm artery reveals human evolution continues?

#79

Post by ncmncm »

cm2187 wrote: post #32
carbocation wrote: post #10

The selection pressure on three versus two arteries feeding the hand has to be so incredibly small (in terms of survival to reproduction in humans) that I am having a hard time imagining how this story has any causal plausibility. Edit to be more clear about what in the article I'm responding to, it's this: > Dr Teghan Lucas from Flinders University says ... “This increase could have resulted from mutations of genes…

Similar evolution with no selection pressure: https://www.independent.co.uk/news/science/wisdom-teeth-evol... I don’t think Darwinism is scientifically established. It has become a bit of a sacred cow because of its opposition with religion, but it is merely a good explanation compatible with the data. That doesn’t prove it. It may be that life evolves and adapts through other mechanism than mere selective pressure.

There is no such thing as "Darwinism" outside of Creationist propaganda.

Evolution by natural selection is directly observed in labs, farm fields, and jungles alike. Biologists are not seeking to "establish" it, but to refine it and place it in context with evolution by sexual selection, by genetic drift, by mutualism, and by other influences less well characterized, not least epigenetics, which acts at the scale of individuals.

I.e., lots of "mechanisms" are known. None contradicts any other. What mix is responsible for a change is often hard to tease out.

Darwin wrote about both natural selection and sexual selection. Which do you imagine to be "Darwinism"?

You would better get your information from people not seeking actively to delude you.

Re: Forearm artery reveals human evolution continues?

#80

Post by ncmncm »

mrfusion wrote: post #33
cm2187 wrote: post #32

Earlier quoted context omitted.

Similar evolution with no selection pressure: https://www.independent.co.uk/news/science/wisdom-teeth-evol... I don’t think Darwinism is scientifically established. It has become a bit of a sacred cow because of its opposition with religion, but it is merely a good explanation compatible with the data. That doesn’t prove it. It may be that life evolves and adapts through other mechanism than mere selective pressure.

I’ve always wondered that. Like why hasn’t evolution itself evolved as well?

What has led you to believe that evolution is not itself continuously evolving in each lineage? What do you imagine DNA is for? What do you imagine sex is for? Do you imagine that sexual reproduction always existed, or that it has had no effect on the lineages where it occurs, or their relative prevalence? How do you imagine those lineages became so prevalent, among multicellular organisms?
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