3.11 Maritime Expansions from a Maritime Ice Age Refuge
61
Age by the high SSTs of the WPWP, may have had at least trading contact with
Near Oceania for tens of thousands of years before this and, as has been suggested,
may have established an early colony in the Sepik River area of New Guinea, 6,000
years ago.
3.11 Maritime Expansions from a Maritime Ice Age Refuge
The close correlation of the maritime trading history of the Spice Islands with the
oceanographic and volcanic history of the WPWP increases the likelihood that the
ancestors of the colonizers of the Pacific are more likely to be found amongst peoples from a maritime Ice Age refuge, with a long maritime history played out within
and on the borders of the WPWP, than amongst migrating rice farmers come lately
from Taiwan. Indeed it would seem more likely for Spice Islanders to have colonized Taiwan, following the Kuro Shio Current north through the WPWP, than for
Near Oceania to have been colonized from Taiwan against the flow of the ancient
north-driving Kuro Shio Current.
A recent paper by Soares et al. [32], which uses complete mitochondrial DNA
genome sequencing to trace the history of haplogroup E, suggests that the direction
of gene flow was in fact from Island Southeast Asia to Taiwan rather than the other
way around:
Whatever the precise origin of haplogroup E may be, spatial frequency distribution and
diversity strongly suggest that the haplogroup arose in ISEA and some of its subclades
spread subsequently to Taiwan. Furthermore, we can infer a timescale for these processes
using the coding region molecular clock. Early subclades are largely restricted to ISEA and
date to the early Holocene. These are E1a1a1 (age 7,700 +/– 3,150 years), E1a2 (age 9,400
+/– 2,850 years), E1b (age 6,850 +/– 2,150 years) and E2b (age 66,700 +/– 1,800 years).
This implies that the diversity of haplogroup E has been accumulating within ISEA for a
minimum of 7,000–10,000 years.
Applying a founder analysis to the subclades found in Taiwan, assuming ISEA as the
source, yielded arrival time estimates of 6,550 +/– 1,850 years ago for E1a and 5,150 +/–
2,950 years for E2b. As these values were quite similar, we also applied a founder analysis
to the entire haplogroup, combining data from both subclades, effectively assuming a single
dispersal. The overall founder age for Taiwan came to 6,250 +/– 1,600 years. These results
indicate that haplogroup E evolved in situ in ISEA and was involved in range expansions
from ~ 12,000 years ago, reaching Taiwan roughly 4,000–8,000 years ago (pp. 1213–1215)
[30].
The authors further note “a very close relationship between the geographical
extent of post-LGM flake-blade industries and the haplogroup E lineages, again
suggesting a close match between archaeological and genetic reconstructions”
(p. 1216). In particular they comment that
Zhang (2000) describes the appearance of a flake-blade industry, based on flakes struck
from multiplatform cores, at 4 coastal sites in east Taiwan, all dated to 5,000–6,000 years
ago. This would fit well with our estimated arrival from the south of E1a lineages in Taiwan
(p. 1216).
61
Age by the high SSTs of the WPWP, may have had at least trading contact with
Near Oceania for tens of thousands of years before this and, as has been suggested,
may have established an early colony in the Sepik River area of New Guinea, 6,000
years ago.
3.11 Maritime Expansions from a Maritime Ice Age Refuge
The close correlation of the maritime trading history of the Spice Islands with the
oceanographic and volcanic history of the WPWP increases the likelihood that the
ancestors of the colonizers of the Pacific are more likely to be found amongst peoples from a maritime Ice Age refuge, with a long maritime history played out within
and on the borders of the WPWP, than amongst migrating rice farmers come lately
from Taiwan. Indeed it would seem more likely for Spice Islanders to have colonized Taiwan, following the Kuro Shio Current north through the WPWP, than for
Near Oceania to have been colonized from Taiwan against the flow of the ancient
north-driving Kuro Shio Current.
A recent paper by Soares et al. [32], which uses complete mitochondrial DNA
genome sequencing to trace the history of haplogroup E, suggests that the direction
of gene flow was in fact from Island Southeast Asia to Taiwan rather than the other
way around:
Whatever the precise origin of haplogroup E may be, spatial frequency distribution and
diversity strongly suggest that the haplogroup arose in ISEA and some of its subclades
spread subsequently to Taiwan. Furthermore, we can infer a timescale for these processes
using the coding region molecular clock. Early subclades are largely restricted to ISEA and
date to the early Holocene. These are E1a1a1 (age 7,700 +/– 3,150 years), E1a2 (age 9,400
+/– 2,850 years), E1b (age 6,850 +/– 2,150 years) and E2b (age 66,700 +/– 1,800 years).
This implies that the diversity of haplogroup E has been accumulating within ISEA for a
minimum of 7,000–10,000 years.
Applying a founder analysis to the subclades found in Taiwan, assuming ISEA as the
source, yielded arrival time estimates of 6,550 +/– 1,850 years ago for E1a and 5,150 +/–
2,950 years for E2b. As these values were quite similar, we also applied a founder analysis
to the entire haplogroup, combining data from both subclades, effectively assuming a single
dispersal. The overall founder age for Taiwan came to 6,250 +/– 1,600 years. These results
indicate that haplogroup E evolved in situ in ISEA and was involved in range expansions
from ~ 12,000 years ago, reaching Taiwan roughly 4,000–8,000 years ago (pp. 1213–1215)
[30].
The authors further note “a very close relationship between the geographical
extent of post-LGM flake-blade industries and the haplogroup E lineages, again
suggesting a close match between archaeological and genetic reconstructions”
(p. 1216). In particular they comment that
Zhang (2000) describes the appearance of a flake-blade industry, based on flakes struck
from multiplatform cores, at 4 coastal sites in east Taiwan, all dated to 5,000–6,000 years
ago. This would fit well with our estimated arrival from the south of E1a lineages in Taiwan
(p. 1216).