That doesn't sound like significant new functionality. All the code for fingers was already there.About the first link that explains that there is a process we have to add new information. For example, people who have the gene mutation that leads to 6 fingers and the finger develops well, they are better at tactile tasks such as a video game (this study was covered in an issue of science news if you are interested). Coincidentaly, this gene is also dominant and depending on the human sexual selection, may take over the population.
True, but that doesn't resolve the issue of how such a mutation could become widespread in a population to begin with. You need that first before you can start talking about reproductive barriers with presumed ancestors.The second article in that context refers to the fact that a F1 hybrid between the hominids with 23 chromosomes and those that didn't would have less fertility, meaning that it widened the gap between human ancestors and chimpanzee ancestors.
So, calculate the odds of such a random mutation happening. Determine if that mutation results in a homozygous or a heterozygous individual. Determine the size of the population. Determine the odds of having a viable offspring with an average mate in the population. Determine the odds of that individual meeting another homozygous or heterozygous carrier of the same mutation.
And then decide whether it really makes sense to propose that the same sort of thing happened over and over again for millions and millions of years, to produce all life as we have it on the earth today. Personally, I don't think it's possible. I don't think the resulting odds are high enough for all of this to occur.
We certainly can't point to where we can see this happening today in the here and now, can we? Without using CRISPR?
Point me to a picture of a significant erosional feature between layers of the geologic column.They aren't that flat. I live in Maryland, so I have seen/visited sideling hill many times. The rock layers are certainly not flat there. Boundaries are very compressed so they appear flat but up close that is out of the picture. If you are wondering why rack changes quickly in the layers is because large changes on Earth occur to separate GTS periods and ages.