/sci/ - Science & Math

Could you explain to me something about genetics:
Why is there two variants of the R1 haplogroup, R1a and R1b, but there's no R1c clade? Or even R1d? what differentiates the clades?

>>11142654
native americans are literally east asian, but more siberian/mongol shifted.

>>10941230
PCA plots basically take every single trait, and put them on a "dimension". So you will have a 2000 dimensional space populated by points of data. Then it will calculate the 2 dimensional cross section through that data which maximizes the difference between groups (this is found algorithmically). That's how you generate a PCA plot (principle component analysis plot)

>>9909693
>Doesn't know what a PCA diagram is.

>>6695741
>>6695731
Racial distinctions aren't arbitrary. You can identify races with unique genetic markers. Again, the classification of races is only meaningful insofar is there are useful differences, such as susceptibility to various diseases. Of course as time goes on and the human race in total becomes more homogenous the usefulness of race specific data will diminish, but currently there are still a lot of people who very neatly fall into one specific genetic group.

There are also some very obvious visible differences between these genetic groups that make it very easy for even a layman to tell them apart, too. Telling by eye isn't as foolproof as a good DNA test but it works pretty well