They use machine learning to decode the nerve impulses in the arm, so you can play video games without moving and can let you synthesize "extra" arms.
search "ctrl labs" and watch the youtube videos, some of scifi possibilities are very interesting.
That's missing the big picture in my opinion. This research indicates the human brain is capable, all on its own, of adapting to entirely new sensorymotor functions. Think of the implications. If some type of new functionality were grafted onto you, you'd be able to control it without having to "reassign" any of your current functions. You could move a "third hand" cursor around in three dimensional virtual space as if it were a virtual body part, not just an interface you have to consciously manipulate like a mouse or keyboard.
We don't know, at least by this study, if the brain can learn once it has developed.
How conscious is that really tho? I don’t think about how to type, I just think thoughts and they come out on the screen. It’s about as conscious as speaking.
Same for the mouse. I don’t think about the mouse consciously, I just look at an item on the screen and choose to interact. Like grabbing a glass of water with my hand.
>I would question how much natural selection applies to rational beings like humans these days.
It's a universal principle, why wouldn't it apply? Each generation is composed of the offspring of those members of the previous generation who reproduced, introducing a statistical bias. Why would it be different "these days", and what has rationality got to do with it?
Besides - as for the notion of 'rational' humans, especially in the context of sex and reproduction - I'll get my coat.
Because ever since we've invented writing (and arguably even before that - ever since we've invented spoken language), we've left the domain of biological evolution. We now accumulate, evaluate and discard knowledge and technology couple orders of magnitude faster than natural processes. From nature's POV, the entire ~10k years of human civilization happened in a blink of an eye (and note that all the interesting things happened arguably in the last couple hundred years).
>Evolution will have hard time identifying genes to promote, when the minimum unit of change is probably "how smart people are" or "how social people are", both having many more reasons for being favoured by natural selection.
If I understand you correctly, that’s just not true. In his seminal work, The Selfish Gene, Richard Dawkins showed that the individual gene is the unit of selection. A genotype that tends to result in a slightly stronger preference for a family life is exactly the kind of thing that could become more prominent, even within one or two generations. I’m sure this is happening right now.
>In your particular example, this arguably derails biological evolution completely - the decision to have kids, and how many kids to have, is dominated by economic and (secondarily) cultural considerations, which change significantly between generations.
I was not making a particular example at all. That is the function of natural selection: it selects for the genotypes had by those who have children who go on to have children themselves.
The selection doesn’t have to happen at the level of a preference for kids. A gene related to diligence or conscientiousness or just about anything else can have effects that ultimately cause differential reproductive success for you and your offspring.
The fact that it’s all too complicated for us to model has bearing on it at all.
Gould came up with the excellent name "punctuated equilibrium" for the discontinuous nature of genetic change, though the math describing it had existed before he popularized the concept.
It is true, though, that all the big changes of the last 10,000 years seem to have been simple changes in individual genes or their expression rather than more complex changes.
Here's a reality check: 6-finger people also have a much higher probability to be bullied at school and thus never reproduce than the others.
In a few more thousand years, we'll either have transcended biology altogether, be extinct, or be back to the kind of pre-civilization environment where the slow work of evolution matters again.
If this principle were true in general, it would imply that evolution didn't exist.
Environments change. Competitive landscapes change. Diets change. Parasites/diseases change.
There are genes in humans that are currently undergoing strong selection.
But it's not true in general, and I gave a specific context: millions of years of human ancestors using their hands to survive in a wide variety of environments and occasionally being born with extra fingers (~0.2% in modern humans, so probably a huge number of opportunities). We have five fingers, so it is unlikely that our six-fingered ancestors had a significant net advantage in general.
I remember reading an article about a present day man with 12 fingers and 12 toes who believes he has an advantage climbing coconut palms. If needs like that had been providing consistent evolutionary pressure on our ancestors, things might be different. Edit: here's a version of it: https://www.cbsnews.com/news/man-with-12-fingers-12-toes-cal...