Page 96 - THE MELANESIA DIASPORA FILE CETAK ISI 10022017

mitochondrial DNA or in the coding areas in mtDNA. The grouping of several haplotypes
are called haplogroups. These mtDNA variations are known to be linked with an individual’s
ethnicity and geographical origin, which is useful in molecular anthropology and forensic
science. The outlook of haplogroups found in Indonesia is an expression of modern human
population migration waves.
Such DNA variations can help create kinship trees or phylogenetic trees based on the
DNA sequences. Sequences of D-loop mitochondrial DNA and coding areas are employed
in order to build phylogenetic trees from the maternal line. Using this method, the earliest
single maternal ancestor of all contemporary humans can be traced genetically to a woman
who lived in Africa around 100,000 years ago. Meanwhile, male migrations can be traced
using the Y-chromosome population marker. This evidence shows that their ancestor
was from Africa, as was the female ancestor traced from the mtDNA. The male ancestor,
referred to as “Adam” and female ancestor, “Eve”, were found to have existed in the same
period of time, that is around 100,000 years ago. After this time in Africa, for unknown
reasons, they or their descendants then migrated out of the area in several waves and
eventually spread to all corners of the planet, hence the description of this as the out of
Africa theory.
The migration out of Africa was not a single occurrence, but rather a series of sporadic
events. The population that left did so in many groups, many waves, and by different
routes. The complete history of these ancestral journeys can be traced using mathematical
calculations from DNA sequences of current populations. Population structures are
established from the distribution of allele variations in populations as well as between
populations. Beside the allele distributions, a phylogenetic or kinship tree analysis that
is developed from various loci in the DNA can be employed to determine the hierarchy of
ancestral orders of certain genetic variations. Phylogenetic trees give information about
the order and distances of the birth period of generations of our ancestors. A phylogenetic
tree can show the presence of non-African populations in a cluster or group of African
variations in Y-chromosome as well as mitochondrial DNA, which both are the main
population markers. Both of the markers can be used to differentiate the genetic grouping
based on the continental origin.
The conclusion that the ancestors of modern humans came from Africa was also
supported by comparing the genetic diversity of current populations in Africa with
populations outside of Africa. It was found that Africa had far more genetic diversity than
outside it. The site of genetic origin is usually highly diverse while the area at the end of

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