In recent years, DNA sequences (nucleotide sequence) of $m t$ DNA and Y chromosomes were considered for the…
In recent years, DNA sequences (nucleotide sequence) of $m t$ DNA and Y chromosomes were considered for the study of human evolution, because:
they are small and therefore, easy to study
they are uniparental in origin and do not take part an recombination
their structure is known in greater detail
they can be studied from the samples of fossil remains
Solution
Sequence of both $m t$ DNA and $\mathrm{Y}$ chromosomes are considered for the study of human evolution because they are uniparental in origin. mtDNA is inherited along with the maternal cytoplasm and $\mathrm{Y}$ chromosome is inherited from father. So they do not take part in recombination. In addition, mtDNA has a higher mutation rate then nuclear DNA so that it is more useful for short term evolutionary studies.
Related Theory
The Y chromosome is in herited from the father; therefore, paternal social class was included in the Y chromosome analysis. Mitochondrial DNA is inherited from the mother; thus, maternal social class was included in the analysis along with paternal social class for mitochondrial DNA. More than $27 \%$ of the variance in Y-haplogroups can be attributed to differences between populations, whereas mtDNA showed much lower heterogeneity between populations (less than 5\%), suggesting a strong influence of patrilocal social structure.