Question

If 99.9% of base sequence among humans are same, then why is there so much diversity in their appearances?

Answer 1

All humans are 99.9 per cent identical and, of that tiny 0.1 per cent difference

onetheless, the scientist found that tiny differences in DNA can provide enough information to identify the geographic ancestry of individual men and women.

In a genome that is 3 billion base pairs, a difference of 0.1% works out to a difference of 3 million bases. When a single base change can change the amino acid sequence of a protein, that can add up to a huge amount of diversity, which is what we see over the nearly 8 billion humans on the planet, and the 99.5% sameness is why we are linked together so closely as a species.