Page 106 - THE MELANESIA DIASPORA FILE CETAK ISI 10022017

Opposite: Family tree and In addition to finding important data about the relationship between diseases and
STRUCTURE analysis on 73 populations, our long-term genetic structure research also provides new insights into the
populations of Asian and non-
Asian populations. The figure population structures and the origins of the Indonesian people. Several initial findings
shows the population code, the exhibited that Indonesia consisted of admixtures from various genetic groups arriving
sampling locations, ethnicity, in a number of waves. The diversity is allegedly due to the geological dynamics of land
and language. The left side is the
language family tree. Southeast formation and the impact of global climate change in the past which caused sea levels to
Asian islands are grouped into one rise, in the process breaking up what was formerly a near continuous land mass into the
cluster. The right-hand section
shows the genetic mixing of each present archipelagic state today. Up to 20,000 years ago, Java and Borneo islands were
population (Hugo Pan-Asian SNP part of mainland Asia. The is called the Sunda Shelf and it was separated from the Sahul
Consortium, 2009). Shelf which was at the time a part of the Australian continent and Papua.
Between the two big land masses separated by sea lay the islands known as Wallacea.
Wallacea includes the islands of Sulawesi, Lombok, Sumbawa, Flores, Sumba, Timor,
Halmahera, Buru, Seram, and many smaller islands. In simple terms, Wallacea consisted of
the island of Sulawesi, Nusa Tenggara, and the Moluccas. It can also be argued that both
the Sunda Shelf and the Sahul Shelf, at the end of glacial era around 18,000 years ago,
formed a range of island which is an integral part of Indonesia in the present. The impact
of climate and environmental change happened in the past must be considered in order
to understand the characteristics of modern populations inhabiting the archipelago in the
present time. In addition, we should note that Indonesian archipelago has been a favored
destination of human migrations since the distant past (Geertz, 1963).
The first wave of migration of early modern humans reached Indonesia around 60,000
years ago. They had come along the coastal zones of Africa, India, and then the Malay
Peninsula down to the Indonesian archipelago. These first migrant groups were the ones
whose present day descendants are the speakers of Papuan languages. Although people
of Papuan appearance are mostly found in the eastern region of Indonesia today, their
genetic traces can be found to different degrees in the general population throughout the
entire archipelago. The percentage is highest in the east, and gets smaller the further west
you go. This trend line is clear, but it conceals a more complex picture.
A detailed description of the variation in percentages of genetic lines and their
admixtures in Asia, including Indonesia has been produced using genome analysis. The
analysis is based on methods used to study the details of population structures in Europe
and their intercontinental mapping.
This approach was employed to map the populations in Southeast Asia and East Asia
using a Genechip filled with 50,000 SNPs. The research was a cooperative effort supported

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