PL 627 Review
Dynamics of Human Diversity: The Case of Mainland Southeast Asia. Edited by N. J. ENFIELD. Canberra: Pacific Linguistics, Australian National University. 2011. 390 pp.
Reviewed by A. BAER
Mainland Southeast Asia is rich in languages, environments, and econo-mies. It also has a complex human DNA heritage. All this is a result of events that happened long before Buddhism, Arabs, or Marco Polo reached Southeast Asia. Given this complexity, prehistory scholars are trying to understand the interrelations of geography, climate, social structure, heredity, and technology in the past, and the significance of this history for today. Dynamics of Human Diversity explores these interrelations. The impetus for the book was a workshop held in 2009 in Siem Reap, Cambodia, on the last 10,000 years in mainland Southeast Asia (MSEA) history. The resulting book is a heady mixture on the region’s past.
Chapter 1, by N. J. Enfield, introduces two questions: Why is there so much biocultural diversity in MSEA and how did it arise? How do different research data and assumptions bias one’s view on the emer- gence of this diversity? The book’s contributors strive to answer these questions. In Chapter 2, J. C. White describes the tropical “bamboo age” and identifies ways this ecological concept can be tested in archeology. MSEA geography and its mosaic ecology have stimulated differentiation among societies, from the highlands to the sea and from the rainforests to the seasonally dry plains.
The ecological concept suggests local biosocial evolution in MSEA, rather than the importation of people, technology, and farming econo- mies from the margins. Some chapters in the book favor intrusions from the north into Malaya based on DNA findings. In Chapter 5, for example, S. Oppenheimer discusses the mitochondrial DNA of MSEA, emphasizing the relationship of Malaya’s Orang Asli to Indochina. Chapter 10, by D. Bulbeck, largely agrees with this view, based mainly on prehistoric human morphology. Neither of these chapters, however, dwells on the theory of invasive rice farmers spreading via China and Taiwan over much of Southeast Asia. This well-known “Austronesian expansion” theory posits a homogeneous cultural tsunami from the periphery, rather than indigenous development. In contrast, local factors may have determined the transition from foraging to farming in MSEA, a view that relegates any Austronesian expansion almost to a non-event.
In Chapter 3, S. E. Hakrow and N. Tayles show how skeletal studies contribute to understanding prehistoric health, demography, and heredity. Chapter 4, again by Enfield, explores the puzzle of MSEA language groups. While the region has many languages (over 150 in the Austroasiatic phylum alone), the five language phyla in MSEA are struc- turally alike. Moreover, while many MSEA people are both multilingual and protective of their culture and mother tongue, other groups have changed their language. Such considerations suggest that language shifts, hybridizations, and cultural diffusion are some of the factors in under- standing this puzzle.
In Chapter 6, H. Jonsson shows how the emic and etic identities of small groups in MSEA change over time as dominant societies gain neighborhood power. The changes have not followed a preordained trajectory, as old European views supposed, but exhibit “contingent dynamics,” depending on the nature and intentions of a particular small group’s dominant neighbors.
Chapter 7, by R. Blench, offers agricultural terms in MSEA language phyla that fit a hypothesis of farming starting in the Sino- Tibetan foothills of the Himalayas and spreading to China, about 6,500 years ago, and then southward. He associates this farming expansion with the emergence of the Daic, Austroasiatic, and Hmong-Mien language phyla. In Chapter 14, P. Sidwell and Blench, based mainly on the terms for taro and rice, put the homeland of Austroasiatic in the middle reaches of the Mekong with dispersal from there likely by boat, both up and down river. Osteological data in Chapter 10 are also held to support an Austroasiatic diaspora from the Mekong.
Chapter 8, by H. Matsumara and others, posits China as the “ultimate source” of both Austroasiatic and Austronesian languages, as well as agricultural technology. Analysis of fossil crania from northern Vietnam versus crania from East Asia and Australasia is held to support the “Two Layer Model” of the peopling of MSEA. That is, the descendents of the first people are judged to be different in cranial measurements from the farming Neolithic people of Vietnam and of most Southeast Asians today, due to immigration from China some 5000 years ago. This is similar to the Austronesian expansion theory. However, in Chapter 9 H. Boonlop and S. Bubpha provide cranial data for Thailand that favors the “Population Continuity Model,” which does not follow the expansion from China theory. Notably, Chapter 8 is the only one in this book that mentions the results of a prominent DNA study favoring population continuity in MSEA throughout prehistory, the so-called “One Layer Model” (HUGO Pan-Asia SNP Consortium. Mapping human genetic diversity in Asia. Science 326: 1541–1545, 2009).
In Chapter 11, by N. Burenhult and others, some enigmas of the Aslian language relationships and lifestyles of the Orang Asli are discussed to produce a new framework of language evolution. Chapter
12 introduces the idea of a “trickle effect” on early Orang Asli heredity, rather than a wave of incoming ancient farmers. In this view by A. Fix, swiddeners who trickled into Malaya descended from the original people of MSEA. After they moved north of Malaya and became swiddeners, some returned to Orang Asli forager areas.
The last chapters are on Austroasiatic (AA) languages. AA is a hall- mark of MSEA, more so than any form of economy, religion, or art. In Chapter 13 G. Diffloth puts the widespread root words for boat, husked rice, and taro into the forefront of the history of the AA phylum. The boat-root is not old enough to help explain any voyages that may have been part of the AA migration models. Husked rice, however, does go back to proto-AA times and taro may also, but this is less certain.
Although Chapter 14 argues for AA arising in the middle Mekong area, Chapter 15, by L. Sagart, suggests that speakers of a language ancestral to AA, perhaps in the Yangzi valley, domesticated rice indepen- dently from other areas. When offshoots of this Yangzi group reached Burma-Thailand-Cambodia, they evolved linguistically into proto-AA.
In the last chapter, G. van Driem reviews the morphology and genetics of modern and ancient rice to suggest that early AA speakers first cultivated one form of rice and Hmong-Mien speakers a separate kind, perhaps in the Brahmaputra basin.
One picture that emerges from this book is of the colonizers of MSEA surviving with a rock and bamboo tool kit and adapting to different ecological zones as their population expanded. Later, economies diversified linguistically and genetically, with some moving from foraging to horticulture and others to swamp-agriculture, setting the stage for the diversity we see today in MSEA, with little of this history being due to developments outside the region. The other major picture of MSEA prehistory is the farming colonization scenario. Both views have some back-up evidence and both have strong supporters.
While there is no index, the major problem with this book is that it costs $80 Australian. Libraries are likely to be the main buyers. Readers who do have access to the book will find it a cornucopia of forward- looking ideas and theoretical frameworks.
A. Baer is an adjunct professor in the Departments of Zoology and History at Oregon State University, Corvallis, Oregon, USA. Her email address is firstname.lastname@example.org