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Home , 8th parallel south, Balabac Strait, Bali Sea, East Indian Archipelago, East Indies, Gulf of Thailand

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Journal of , 27, I 153-l I67 ,

Maps of levels in Southeast : shorelines, river systems and durations Harold K. Voris Field Museum of , Chicago, Illinois, USA

Abstract Aim Glaciation and deglaciation and the accompanying lowering and rising of sealevels during the late Pleistoceneare known to have greatly affected land massconfigurations in SoutheastAsia. The objective of this report is to provide a seriesof mapsthat estimatethe areasof exposed land in the Indo-Australian during periods of the Pleistocenewhen sealevels were below present day levels. Location The maps presentedhere cover tropical SoutheastAsia and Austral-Asia. The east-westcoverage extends 8000 km from to . The north- coverage extends 5000 km from to Australia. Methods Present-day bathymetric depth contours were usedto estimate past shore lines and the locations of the major drowned river systemsof the Sunda and Sahul shelves. The timing of sea level changesassociated with glaciation over the past 250,000 was taken from multiple sourcesthat, in some cases,account for and sub- sidenceduring the period in question. Results This report provides a seriesof maps that estimate the areasof exposed land in the Indo-Australian region during periods of 17,000, 150,000 and 250,000 years before present. The ancient shorelinesare basedon present day depth contours of 10, 20, 30, 40,50,75, 100 and 120 m. On the maps depicting shorelinesat 75,100 and 120 m below present levels the major Pleistoceneriver systemsof the Sunda and Sahul shelvesare depicted. Estimatesof the number of major sealevel fluctuation events and the duration of time that sealevels were at or below the illustrated level are provided. Main conclusions Previousreconstructions of sea-levelchange during the Pleistocenehave emphasizedthe maximum lows. The perspectiveprovided here emphasizesthat sea levels were at their maximum lows for relatively short periods of time but were at or below intermediate levels (e.g. at or below 40 m below present-day levels) for more than half of each of the time periods considered.

Keywords Sealevels, Pleistocene,, maps, biogeography, palaeogeography.

(e.g. Inger & Chin, 1962; Heaney, 1985, 1991; Morley & iNTRODUCTlON Flenley,1987; Rainboth, 1991; Dodsonet al., 1995; How & The importance of changingsea levels over geologicaltime Kitchener, 1997). Thesestudies cite a variety of sourcesthat has long been consideredessential to our understanding leadback to Molengraaff & Weber (1919, X921), Molengraaff the distribution of both aquatic and terrestrial organisms (1921),van Bemmelen(1949), Kuenen (1950), Beaufort (1951), (Molengraaff & Weber, 1919; Darlington, 1957; Wallace, Wyrtki (1961),Emery et al. (1972);Biswas (1973), Verstappen 1881). Many of the zoogeographicworks that considerthe (1975), Batchelor (1979), Potts (1983) or Gibbons & Clunie Indo-Chinese and Indo-Australian recognize the (1986). Theseauthors’ maps vary but mostare limited to estim- importance of the Sundaand Sahulshelves in forming land ating the extent of exposedcontinental shelf at a particular bridgesand connectingriver systemsduring the Pleistocene past sealevel, usually 100 m below presentlevels (BPL) and, in somecases, illustrating palaeo river systemson the Sunda and Sahulshelves. Their mapsprimarily serveto illustratehow Correspondence: Department of Zoology, Field’Museum of Natural History, 1400 S. Lake Shore Drive, Chicago, Illinois 606052496 USA. E-mail: the SundaShelf connectsthe major islandsof the Indonesian [email protected] (Sumatra, and )with Indochina and I 8 2000 Blackwell Science Ltd I I54 H. K.Voris how the forms a broad connection between _ - Hydrographic and maps, a National Geographic Australia and New . The documentation for many of hydrographic map and WORLDBATH, based on more than these maps was limited and the authors did ,not relate the seven million soundings taken -wide. Appendix I map contours to particular time periods or rime durations. provides details on these sources and the specific charts that Sea-level changes over the past 30 Ma have been well were consulted. documented in association with tectonic changes (Hall & Holloway, 1998),&d glaciation over the past 250,000 years River systems (Ollier, 1985; Matthews, 1990; Dawson, 1992). Papers that focus on sea-level changes during the Pleistocene generally The estimated locations of the major river systems of the Sunda infer sea levels from either geological mapping of retreating and Sahul shelves were based on present day bathymetric shoreline margins e.g. the use of reef terraces ‘on trop- depth contours (see Appendix I) as well as the original maps ical coasts (Bloom & Yonekura, 1990) or the marine oxygen that appear in Molengraaff & Weber (1919), Molengraaff isotope record e.g. deviations from the standard of the 1e0/160 (1921), van BeXmelen (1949), Kuenen (1950), Wyrtki (1961), ratios in foraminiferal tests from deep sea cores (Fairbanks, Emery et al. (1972), Ollier (1985) and Rainboth (1991). The 1989). Typically, these papers present graphical representa- largest of these rivers, the North ,Sunda River, is well defined tions of estimated sea levels plotted over time. by ‘.., a wonderful set of long winding valleys, starting off The objective of this report is to provide a series of maps the mouths of many important rivers and joining in the centre that estimate the areas of exposed land in the Indo-Australian to form a huge north-running channel’ (Kuenen, 1950). In region during periods of the Pleistocene when sea levels were other areas of low in the Pleistocene, such as the Java below present levels. The major river systems on the Sunda Sea and the Gulf of , sedimentation has been extens- and Sahul shelves are depicted on three of the maps. In ive (Emery & Nino, 1963; Emery et&, 1972; Tjia, 1980) addition, estimates of the number of major sea-level fluctuation and the exact location of many of the rivers is largely hypo- events and the duration of time that sea levels were at or below thetical and certainly varied over time due to meandering the illustrated level are provided for a range of sea levels. (Kuenen, 1950; Rainboth, 1991; Bird, 1993). For example, echo sounding profiles south of the Sampit River off the southern coast of Borneo provide visualizations of river valleys MATERIALS AND METHODS 400, 1200 and 5400 m in width (Wyrtki, 1961). The Gulf of Carpenteria River system on the Sahul Shelf is less well Depth contours as past shore lines documented but the fluctuating salinities of Lake Carpentaria In this report present day bathymetric depth contours are during the Pleistocene suggest a complex estuarine embay- used as proxies for previous shore lines at particular ment (Torgersen et al., 1985). In addition, the shallow and in the past 250,000 years before present (yr BP). Sources narrow straits of the Aru support the presence of used to estimate these contours included the General Pleistocene rivers draining west from to the Bathymetric Chart of the (GEBCO) Series, US edge of the Sahul Shelf (Umbgrove, 1949). _-_

Table I The approximate amount of time during past Pleistocene intervals that sea levels were at or below present levels (BPL)is estimated and the percentage of the period is given. The sources were Fairbanks (1989), Bloom & Yonekura (1990) and Chappell & Shackleton (1986) for 17,000,150~000 and 250,000 yr BP, respectively.

Past 17,000 years Past 150,000 years Past 250,000 years Sea level BPL (m) Years’ % of time’ Events3 Years % of time Events Years % of time Events

120 1,000 6 1 3,000 2 ‘1 15,000 6 2 100 4,000 24 1 7,000 5 1 29,000 12 2 75 5,500 32 1 14,000 9 1 42,000 17 2 50 7,000 41 1 40,000 27 5 99,000 40 5 40 7,500 44 1 65,000 43 7 136,000 54 6 30 8,400 49 1 93,000 62 5 167,000 67 6 20 9,200 54 1 107,000 71 4 201,000 80 6 10 11,000 65 1 134,000 89 3 227,000 91 3

1 Approximate number of years in each time period (i.e. past 17,000,150,000 or 250,000 years), that the sea level was at or below the level shown in column 1. ’ Approximate percentage of years in each time period (i.e. past 17,000,150,000 or 250,000 years) that the sea level was at or below the level shown in column 1. 3 The estimated number of times within each time period (i.e. past 17,000, 150,000 br 250,000 years) that the sea level fell below the level shown in column 1.

0 Blackwell Science Ltd 2000,~oomal ofBiogeography, 27, I 153-l 167 Pleistocene sea-level maps of Southeast Asia I I55

stood (Bloom & Yonekura, 1990, p. 104). Usingpresent day Time estimates and events of sea level fluctuakon depth contours as proxies for past sea levels assumesthat’ Sea-levelchanges associated with glaciation over the past within the 250,000- time frame and a 120-m sea-level 250,000 yr BP have beenestimated by severalresearch teams change,tectonic uplift and subsidence,tidal scouringand the focusingon this entire period or a subsetof this period (e.g. accumulationof sedimentswere eitherrelatively minor factors Milliman & Emery, 1968; Shackleton,1987; Pirazzoli, 1991). affecting present day depth contours or that they are well The time estimatesfor the duration of particular past sea understoodand can be factored into estimatesof sea level. levelspresented here for 17,000, 125,000 and 250,000 yr BP The papersthat provide estimatesof sealevels over the past are basedon relatively recent works that attempt to take into 17,000 years considertectonic uplift or subsidenceto be a accountmultiple sourcesof data and, in somecases, account minor factor (Tjia et al., 1984), but estimatesspanning the for tectonicuplift and subsidenceduring the period in question past 150,000-250,000 years recognizethat estimateduplift (e.g. Bloom & Yonekura,1990). Estimatesof amountsof time or subsidencerates of asmuch as 1.5 m per 1000 yearsgreatly at or belowa particular sealevel were obtainedby scrutinizing complicate the interpretation of oxygen isotope and coral publishedgraphs. The time estimatesfor the past 17,000yr BP reef data (Bloom & Yonekura, 1990). Thus, the maps pre- presentedin Table 1 are basedon changesin oxygen isotope sentedhere are best understoodand interpreted asa seriesof deviations presentedin figure 2 in Fairbanks (1989). Time approximationsto be refined asnew data accumulate. estimatesfor the past 150,000 yr BP (Table 1) are basedon From the perspectiveof a zoogeographereach map illus- figure 6.3 in Bloom & Yonekura (1990) which depicts sea trates one or more general points. At 120 m BPL (Fig. la, levelsgrounded on data obtained from coral-reef terracesin c. 17,000 yr BP), the bulk of the Sunda and Sahul shelves PapuaNew Guinea.The estimatesfor the past 250,000 yr BP were largely exposedand formed massivelowland connec- (Table 1) are basedon figure 4B in Chappell & Shackleton tions betweenpresent day islandsin this region and adjacent .(1986). The latter figureis basedon data obtainedfrom coral- ., Java and Borneo are connectedby the reef terracesin PapuaNew Guineaand adjustedwith oxygen exposedSunda Shelf. If one considersnew contiguous shelf isotopedeviation data. Events,_ here refer to the number of exposedsouth and east of the of Kra, an additional times the sealevel dropped below a particular level. Events 1.53 million sq km of land was annexed to SoutheastAsia. were estimatedfor each sealevel and time period usingthe This areais three-fourths the presentday combinedareas of samepublished graphs that were used to determinetime , Thailand, , ,, the durationscited above. Peninsulaand (2.07 million sq km) (Webster’s, 1980). At 120 m BPL, the total newly connectedarea of the SundaShelf (including Sumatra,Java and Borneo) exceeded Maps 5 3.2 million sqkm, thus increasingthe contiguousarea of Indo- Figure 1 providespalaeo sea-level reconstructions for tropical by about 1.5 times. In addition, the islandsof Hainan SoutheastAsia and Austral-Asia basedon depth contoursof and Taiwan were connectedto mainlandChina, and Sri Lanka 10,20, 30,40, 50, 75, 100 and 120 m. The origin of the base wasconnected with . Natuna Islandand the other smaller maps presentedhere is a Geographicprojection in ArcView islandsof today’s (e.g. Anambas Islands (Environmental SystemsResearch Institute, Inc.) that is very and TambelanArchipelago) were a part of the exposedSunda similar to an Equal Area Cylindrical projection. The Geo- Shelf and likely offered somesignificant topographic relief. graphicprojection has minimal area distortion near the . Although Borneoand Palawanwere not connectedby a land bridge at 17,000 yr BP, the BalabacStraits were reducedto a width of only about 12 km. Sulawesiremained separated Availability of maps from Borneoby a narrow but very deepocean trench. To the Copyrights on the maps publishedhere belong to the Field east the exposed Sahul Shelf broadly connected Australia Museumof Natural History (0 2000 Field Museumof Natural and New Guineaand surroundedthe AruIslands. History, Chicago,Illinois, USA). Black and white and colour At 100 m and 75 m BPL (Fig. lb, c, c. 15,000 and versionsof the mapsthat appearhere may be obtainedfrom 13,000 yr BP), the configuration of the exposed Sunda and the author for non-commercial,scholarly, scientific or edu- Sahulshelves remained very similarto the 120 m BPL arrange- cational purposes.These maps may be downloaded from ment and no major land connectionswere lost. At 75 m BPL the World Wide Web at http://fmnh.org/research-collections/ (Fig. lc), it is likely that one or more freshwater lakes or zoology/zoo-sites/seamaps/.The maps may be downloaded, swampsexisted at various times in depressionswhere the copied, modified and re-publishedfor non-commercialpur- Gulf of Siam is now located (Emery & Nina; 1963) and posesas long asthis publicationis cited and the Field Museum bottom corestaken off the eastcoast of the is credited. containedpeat depositsindicating a Pleistocenepeat swamp (Biswas,1973). Furthermore, evidence of old coastlines support the presenceof a brackishwater lake in the DISCUSSION at about 60 m BPL (Torgersenet al., 1985). It is important to note that the maps, tables and graphs At 50 m BPL (Fig. Id, c. 11,000yr BP), extensiveland bridges presentedhere are approximationsbased on data that have still connectedthe Malay Peninsula,Sumatra, Java and Borneo. sizable error margins which are usually not fully under- At 50 m BPL (Fig. Id), Natuna , Midai Island and the

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Anambas Islands were isolated from the mainland (Parke et al., 1972; Tjia, 1980; Ollier, 1985; Heaney, 1991), while etal., 1971). In addition, Taiwan was no longer connected others for no apparent reasonhave included two separate to (Nino & Emery, 1961), and the Gulf of parallel rivers running north (e.g. Rainboth, 1991; 1996a; Thailand, the and the Gulf of Carpentaria became 199613).The presentday depth contours (e.g. seeKeller & significant . At 50 m BPL, the North Sunda River that had Richards, 1967) strongly suggestthat a singleriver drained at lower sea levels provided freshwater corridors and perhaps north as illustratedin Fig. l(a) and depictedby van Bemmelen gallery corridors between Sumatra and Borneo was (1949),Beaufort (1951) and Verstappen(1975). largely eliminated (see Fig. la, b and c for rivers). At 40 m BPL (Fig. le), land bridges still connected the Siam River system Malay Peninsula, Sumatra and Java. At 40 m BPL, the cormec- 1 (ion between Borneo and Sumatra (via Bangka, and Another large river systemincluded Sumatra’s Sungai Kampar the Karimata Islands) was perhaps as wide as 150 km, or a that ran north through the SingaporeStraits, was joined by long narrow channel may have separated them (Fig. le). At the Johore River and then ran north over a large expanseof 30 m BPL (Fig. lf), the connection was likely to have been the (Fig. la). This river likely joined branches lost (Umbgrove, 1949; Emery et al., 1972; Ben-Avraham & from the when sealevels were 120 m BPL. Emery, 1973). At 40 m BPL, Pulau Tioman remains connected The main river bed located in the Gulf of Thailand has been to the Malay Peninsula and the Tambelan archipelago remains obscuredby extensivesilt depositsbut it must have included connected to Borneo. At 30 m BPL, Tambelan Island was major contributions from Sungai Endau, Sungai Pahang, separate from the coast of Borneo but Tioman was likely still SungaiTerengganu and SungaiKelantan of the eastcoast of connected to the .mainland. At 20 m BPL (Fig. lg), it is likely PeninsularMalaysia and, of course,Thailand’s Chao Phraya that no land bridges existed between the Malay Peninsula, River. Someauthors show Sumatra’sSungai Kampar flowing Sumatra, Java and Borneo, although it is possible that the south-eastalong the coast of Sumatraand then north to join Malay Peninsula and Sumatra were connected by a largely the North SundaRiver, avoiding the SiamRiver system(e.g. freshwater estuary. At this level, Banka Island remained con- Beaufort, 1951; Heaney, 1991; 1996b; Rainboth, 1996a) nected to the low alluvial plane of east Sumatra but Belitung while Umbgrove(1949), van Bemmelen(1949), Wyrtki (1961), Island had become separated (Emery et al., 1972; Ben-Avraham Verstappen(1975) and Ollier (1985) show it flowing to the & Emery, 1973). In addition, Hainan, and Aru were Gulf of Thailand as in Fig. l(a). Although the latter depic- not cannected by land bridges to their adjacent mainlands tion seemsto conform best to observed bathymetry (see (Umbgrove, 1949; Nino & Emery, 1961). With sea levels as Keller & Richards,1967) the two opposingarrangements have little as 10 m BPL (Fig. lh), New Guinea apparently remained very different biogeographicimplications and merit further largely connected to Australia at the Torres Straits (Jennings, investigation. 1972), and Melville Island remained contiguous with Australia. North Sunda River system Palaeo river systems The largestof the major SundaShelf rivers (the Molengraaff The Pleistoceneriver systemsof the Sundaand Sahulshelves Rivers of Dickerson (1941) ) was undoubtedly the North are most extensive in the map showing sealevels at 120 m SundaRiver flowage(Kuenen, 1950; Tjia, 1980)that ran north BPL (Fig. la) and they are -mostrelevarh to the 17,000 yr BP from the north-eastcoast of Sumatra(Sungai Indragiri, Sungai time frame. First, it is worth noting that the largest rivers Hari and SungaiMusi) to join the large from of today’s mainland SoutheastAsia (,Brahmaputra, Borneo before entering the seanorth-east of Natuna Island. Irrawaddy, Salween, and ) are not greatly Most authors agreeon this river system(Fig. la) and some extended even at 120 m BPL. However, on the Sunda Shelf of its river valleys have been located and mappedin detail there were severalvery large river systems.To get a senseof (e.g. Molengraaff, 1921). At sealevels at or below 75 m BPL the sizeof theseancient flowages and the connectionsthat they (Fig. lc), this river joined many rivers of Borneoand Sumatra formed, consider the following summary of only the chief and had a major influenceon the dispersalof fresh water elements. fishes(Inger & Chin, 1962).

Malacca Straits River system East Sunda River system The flowage between the Malay Peninsula and Sumatra Further east,another hugeriver system,the EastSunda River running north-west to the Andaman Seahad as tributaries (van Bemmelen,1949; Tjia, 1980), ran east acrosswhat is several of today’s major Sumatran rivers (including Sungai now the Java Seato enter the sea near Bali. This system SimpangKanan, Sungai Panai, Sungai Rokan and SungaiSiak) includedvirtually all the modernday rivers of the and no fewer than four large rivers along the west coast of of Java, the southcoast of Borneoand the northernportion of PeninsularMalaysia (includingSungai , SungaiBernam, the eastcoast of Sumatra. A much smallerriver with tribu- Sungai Muar and Sungai Lenek). Some authors have not taries in south-east Sumatra and the Thousand Islands included this drainage on their maps (e.g. Molengraaff & (Seribu’Islands)area of the Java Seaflowed south through Weber, 1919; Molengraaff, 1921; Umbgrove, 1949; Emery the SundaStraits to enter the Indian (Umbgrove, 1949;

0 Blackwell Science Ltd 2000, Journal of Biogeography, 27, I 153-l I67 Pleistocene sea-level maps of Southeast Asia I I65

the Java basin (e.g. Verstappen, 1975; Olliel; 1985; Rainboth, 1991; 1996a, b).

Other considerations

At the time of the last glacial maxima (17,000 yr BP, sea level 120 m BPL; Fairbanks, 1989) ,cliiates in Southeast Asia were _-_--_ drier and more seasonal than today’s climates (Whitmore, 1981; Morley & Flenley, 1987; Heaney, 1991; Dawson, .,. ),.’ 1992; Shackleton, 1994) and thus river discharge probably .$Q’/Z,..,..,.~ .;..,..,....,..,..#d varied from today’s volumes. However, it is noteworthy that 521’7’ at the glacial maximum (e.g. 17,000 yr BP) the Siam River Fl::,::,::/: system was approximately equal in length to the present day Mekong River drainage. Recognition of the size and inter- connectedness of these major systems has and will continue to provide a powerful tool for understanding the distributions and relationships of present day freshwater faunas (Rainboth, 1991; Dodson et al., 1995; 1996b). Each map has a small inset graph indicating the estim- ated amount of time during the past 17,000, 150,000 and 250,000 yr BP that the sea level was at or below the level depicted on the map. Figure 2 summarizes these data and illustrates two points: (1) sea levels were at their maximum lows for relatively short periods of time; and (2) sea levels were at or below 30 and 40 m BPL for more than half of each of the time periods considered. Previous reconstruc- tions of sea-level changes have emphasized the maximum lows only. Figure 2 and Table 1 reinforce the notion that maximum sea-level regression is only one factor in under- standing the historical biogeography of the region. The let&of time at or below particular sea levels and the number of times sea levels fell below particular levels were very likely to be __--_--_-._____.-._..--..--.. equally important factors in the dispersal of plants and .

______---._____--....----.

____-______-______ACKNOWLEDGMENTS

_____-_..._____-. The author is indebted to Clara Simpson, the scientific __----_.______-- illustrator who drew the maps presented in this publication. _--rl---d--- Clara Simpson’s skill in map interpretation and computer graphics proved invaluable and her patience with the innumer- able modifications and refinements is greatly appreciated. I 10 20 30 40 so 75 100 120 also wish to thank Julian Dodson, Jack Fooden, Larry Heaney, Meten at or below present 888 level Robert Inger, Daryl Karns, John Murphy and Helen Voris for 4 helpful comments and suggestions. Thanks also go to Chris Figure 2 Bar graphs illustrating estimates of the percentageof Winters at the University of Chicago Map Library for his time that the sea level was at or below 10,20,30,40,50,75,100 kind assistance and special thanks go to Ingrid Fauci for her d and 120 m below its present level during the past 17,000,150,000 and 250,000 years. The time estimates for 17,000,150,000 and help and determination with the search for relevant literature. 250,000 years intervals are based on Fairbanks (1989), Bloom & Yonekura (199 0) and Chappel & Shackelton (19 86), respectively. REFERENCES Batchelor, B. C. (1979) Discontinuously rising late Cainozoic van Bemmelen, 1949). Modern-day bottom contours and eustatic sea-levels, with special reference to , South- bottom sediments (Ben-Avraham & Emery, 1973; Tjia, 1980) . Geologic En Mijnbouw, 58, l-20. strongly indicate that the East Sunda River had a single main -deBeaufort, L. F. (1951)Zoogeography of the Land and Inland cha nel (Molengraaff & Weber, 1919; Beaufort, 1951; Wyrtki, Waters, 208 pp. Sidgwick and Jackson Ltd, London. 196 ; Emery et al., 1972; Tjia, 1980; Heaney, 1991) as shown Ben-Avraham, Z. & Emery, K. 0. (1973) Structural framework in F’g.1 l(a). However some authors, without providing an of Sunda Shelf. American Association of Petroleum Geologists explanation, show two parallel rivers running east through Bulletin, 57,2323-2366.

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Bird, E. C. F. (1993) Submerging Coasts: the Effects of a Rising Matthews, R. K. (1990) Quaternary sea-level change. Sea-level Sea Level on Coastal Environments. John Wiley & Sons, Ltd, change. Committee on Global Change, National Research Chichester. Council, Studies in Geophysics, pp. 88-103. National Academy Biswas, B. (1973) Quaternary changes in sea-level in the South Press, Washington, DC. China Sea. Bulletin of the Geological Society of , 6, Milliman, J. D. & Emery, K. 0. (1968) Sea levels during the 229-256. past 35,000 years. Science, 162,1121-1123. Bloom, A. L. & Yonekura, N. (1990) Graphic analysis of dislocated Molengraaff, G. A. F. (1921) Modern deep-sea research in quaternary shorelines. Sea-level change. Committee on Global the . Geographical Journal, 57, 95- Change, National Research Council, Studies in Geophysics, 121. pp. 104-115. National Academy Press, Washington, DC. Molengraaff, G. A. E & Weber, M. (1919) Het verband tusschen Chappell, J. & Shackleton, N. J. (1986) Oxygen isotopes and den plistoceenen ijstijd en het ontstaan der Soenda-zee (Java- en sea level. , 324, 137-140. Zuid-Chmeesche Zee) en de invloed daarvan op de verspreidmg Darlington, I? J. (1957) Zoogeography: the Geographical Distribu- der koraalriffen en op de land-en zoetwater-fauna. Verslag Van tion of Animals. John Wiley & Sons, Inc., New York. de &wDne Vergaderingen a& W&En Natuurkundige Afdeeling, Dawson, A. G. (1992) Ice age , late quaternary geology ’ 28,497-544. and climate. Routledge Physical Environment series, 293 pp. Molengraaff, G. A. F. & Weber, M. (1921) On the relation Routledge, London & New York. between the Pleistocene glacial period and the origin of the Dickerson, R. E. (1941) Molengraaff River: a drowned Pleis- Sunda Sea (Java- and South China-Sea), and its influence on tocene stream and other Asian evidences bearing upon the the distribution of coralreefs and on the land- and freshwater lowering of sea level during the Ice Age. Proceedings University fauna. Proceedings of the Section of Sciences, 23, 395-439. of Pennsilvania, Biceetennial Conference (ed. E. A. Speiser), [English ]. pp. 13-20. University of Pennsylrania Press. Morley, R. J. & Flenley, J. R. (1987) Late Cainozoic vegeta- Dodson, J. J., Colombani, F. & Ng, I? K. L. (1995) Phylogeo- tional and environmental changes in the . graphic structure in mitochondrial DNA of a South-east Asian Biogeographical Evolution of (ed. by freshwater fish, nemurus (Siluroidei; ) T. C. Whitmore), pp. 50-59. Clarendon Press, Oxford. and Pleistocene sea-level changes on the Sunda shelf. Molecular Nino, H. & Emery, K. 0. (1961) Sediments of shallow portions Ecology, 4,331-346. of and South China Sea. Geological Society of Emery, K. 0. & Nino, H. (1963) Sediments of the Gulf of America Bulletin, 72,731-762. Thailand and adjacent . Geological Society Ollier, C. D. (1985) The geological background to in of America Bulletin, 74,541-X4. island Southeast Modern quaternary Research in South-East i Emery, K. O., Uchupi, E., Sunderland, J., Uktolseja, H. L. & Asia, 9 (ed. by G. Bartstra and W. A. Casparie), pp. 25-42. Young, E. M. (1972) X. Geological structure and some water A. A. Balkema, Rotterdam. characteristics of the Java Sea and adjacent continental shelf. Parke, M. L., Jr, Emery, K. O., Szymankiewicz, R. & Reynolds, L. M. United Nations ECAFE, CCOP Technical Bulletin, 6,197-223. (1971) Structural framework of, continental margin in South Fairbanks, R. G. (1989) A 17,000-year glacio-eustatic sea level China Sea. American Association of Petroleum Geologists record. influence of glacial melting rates on the Younger Dryas Bulletin, 55, 723-751. event and deep ocean circulation. Nature, 342, 637-642. Pirazzoli, l? A. (1991) World Atlas of Sea-Level Changes. Gibbons, J. R. H. & Clunie, E G. A. U. (1986) Sea level changes Elsevier Series, 58. Elsevier Science Publishers, and pacific prehistory. Journal of Pacific History, 21,58-82. New York. Hall, R. & Holloway, J. D., eds (1998) Biogeography and Geo- Potts, D. C. (1983) Evolutionary disequilibrium among Indo- logical Evolution of SE Asia, 417 pp. Backhuys Publishers, Pacific , Bulletin of Marine Science, 33,619-632. Leiden. Rainboth, W. J. (1991) Cyprinids of South East Asia. Cyprinid Fishes: Heaney, L. R. (1985) Zoogeographic evidence for middle and Systematics, Biology and Exploitation (ed. by I. J. Winfield and late Pleistocene land bridges to the Philippine Islands. Modern J. S. Nelson), pp. 156-210. Chapman & Hall, London. quaternary Research in South-East Asia, 9 (ed. by G. Bartstra Rainboth, W. J. (1996a) Fishes of the Cambodian Mekong, and W. A. Casparie), pp. 127-143. A.A. Balkema, Rotterdam. 265 pp. Food and Agriculture Organization of the United Heaney, L. R. (1991) A. synopsis of climatic and vegetational Nations, Rome. change in southeast Asia. Climatic Change, 19,53-61. Rainboth, W. J. (1996b) The , systematics and zoo- How, R. A. & Kitchener, D. J. (1997) Biogeography of Indonesian of Hypsibarbus, a new of large barbs (Pisces, snakes. Journal of Biogeography, 24,725-735. Cyprinidae) from the rivers, of southeastern Asia. Universiey Inger, R. F. & Chin Phui Kong (1962) The fresh-water fishes of of California Publications in Zoology, 129, xxiii-199. . Fieldiana Zoology, 45,1-268. Shackleton, N. J. (1987) Oxygen isotopes, ice volume and sea Jennings, J. N. (1972) Some attributes of Torres Strait. Bridge level. Quaternary Science Reviews, 6, 183-190. and Barrier: the Natural and Cultural History of Torres Strait Shackleton, N. J. (1994) The climate system in the recent geological (ed. by D. Walker), pp. 29-38. Australian National University past. Paleoclimates and their Model&g (ed. by J. R. L. ‘Allen, of Canberra, Canberra. B. J. Hoskins, B. W. Sellwood, R. A. Spicer and I? J. Valdes), Keller, G. H. & Richards, A. E (1967) Sediments of the pp. l-5. Chapman & Hall, London. Strait, Southeast Asia. Journal of Sedimentary Petrology, 37, Tjia, H. D. (1980) The Sunda shelf, Southeast Asia. Zeitschrift fir 102-127. Geomorphologie N. F., 24,405-427. Kuenen, Ph.H. (1950) Marine Geology. John Wiley & Sons, Inc., Tjia, H. D., Sujintno, S., Suklija, Y., Harsono, R. A. F., Rachmat, A., New York. Hainim, J., & Djunaedi, (1984) Holocene shorelines in the

@ Blackwell Science Ltd 2000,~ournol of&ogeogmphy, 27, I 153-l 167 Pleistocene sea-level maps of Southeast Asia I I67

Indonesian tin islands. Modern quaternury Research in South- Wallace’s Line and (ed. by T. C. Whitmore), East Asia, 8 (ed. by G. Bartstra and W. A. Casparie), pp. 103- pp. 36-42. Clarendon Press, Oxford. 117. A.A. Balkema, Rotterdam. Wyrtki, K. (1961) Physical oceanography of the Southeast Asian Torgersen, T., Jones, M. R., Stephens, A. W. & Searle, D. E. & waters. NAGA Report, Vol. 2. Scientific Results of Marine Ullman, W. J. (1985) Late Quaternary hydrological changes Investigations of the South China Sea and the Gulf of Thailand in the Gulf of Carpentaria. Nature, London, 313, 785-787. 19.59-61. University of California Press, La Jolla. Umbgrove, J. H. F. (1949) Structural History of the., xi-63 pp. Cambridge University Press, Cambridge. van Bemmelen d. W. (1949) The Geology of , Vol. IA, pp. xxiii-732. Government Printing Office, . Verstappen, H.Th. (1975) On palaeo climates and landform L development in . Modern quaternary Research in Soutb- East Asia, 1 (ed. by G. Bartstra and W. A. Casparie), pp. 3-35. Harold K.Voris is Curator and Head of the Division of A.A. Balkema, Rotterdam. an4 Amphibians at the Field Museum of Natural History. Hib interests in the systematics and ecology of Wallace, A. R. (1881) Island life or the phenomena and causes I the marine and semi-aquatic snakes of Southeast Asia have of insular faunas and floras including a-revision and attempted extended over the past 35 years. Recently Dr Voris and solution of the problem of geological climates. Macmillan, London. several colleagues have focused their efforts on the ecology Webster’s new geographical dictionary (1980) G. & C. Merriam and evolution of and estuarial snakes of the Indo-Australian region. Co., Springfield, MA. Whitmore, T. C. (1981) Palaeoclimate and vegetation history. 1 Appendix I The charts, maps and web sites consulted to determine the present-day depth contours used to characterize Pleistocene shore lines when sea levels were below present-day levels.

Topography from WORLDBATH [http://ingrid.ldgo.columbia.edu/SOURCESI WORLDBATHlbathl]. This is the ETOPOS 5 x 5 minutes Navy database, giving bathymetryltopography on a 5 minute by 5 minute grid. WORLDBATH data are taken from the National Geophysical Data Center (NGDC), under the National Oceanic and Atmospheric Administration (NOAA). General Bathymetric Chart of the Oceans (GEBCO) Series established by HSH Prince Albert I of Monaco in 1903.Sth. Edition, April 1979. . Scale 1 : 10,000,000 at the equator. Heights and depths in meters. Map numbers 5.05,5,06,5.09,5.10. National Geographic Maps of the’world, National Geographic Society, Washington, D.C. USA. World Ocean Floors, , 1992. National Imagery and Mapping Agency [United States Defense Mapping Agency]. Chart No. 3122, Sumatra-West Coast, Singkel to Padang including Adjacent Islands. 1st ed. 1942, scale 1 : 500,000. Chart No. 3132, Asia, South China Sea, Gulf of Siam. 4th ed. 1954, scale 1 : 959,000. Chart No. 3133, Asia, Federation of -Thailand, Gulf of Siam, Kuala Trengganu to Nakhon Roads, 5th Ed. 1955, scale 1 : 496,000. Chart No. 63250, Asia, India-Sri Lanka, Palp Strait and , 5th ed. 1983, scale 1 : 310,350. Chart No. 71018, Indonesia, Western Portion of Jawa including Selat Sunda. 10th ed. 1996, scale 1 : 497,000. Chart No. 71027, Pulau Bintan to Mui Ca Mau including North Coast of Borneo and Adjacent Islands. 8th ed. 1991, scale 1 : 1,091,700. Chart No. 71033, Indonesia-Malaysia-Singapore-Australia, Western Part of Java Sea and Southern Passagesto China. 31st ed. 1996, scale 1 : 1,613,850. Chart No. 71180, Indonesia, Selat Sunda and Approaches. 29th ed. 1996, scale 1 : 290,480. Chart No. 71265, Singapore-Malaysia-Indonesia, Singapore Area. 2nd ed. 1996, scale 1 : 200,000. Chart No. 71295, Asia;Indonesia-Malaysia, - Northwest Part. 1st ed. 1991, scale 1 : 300,000. Chart No. 72014, Indonesia-Malaysia- , Sandakan Pelabuhan to Sungai Mahakan including the Northern Portion of Strait. 10th ed. 1996, scale 1 : 750,000. Chart No. 72035, Indonesia, Eastern Portion Jawa including Madura, Bali, and Lombak. 8th ed. 1998, scale 1 : 497,000. Chart No. 72223, , Indonesia, Selat Bali. 8th ed. 1995, scale 1 : 200,000. Chart No. 73024, Indonesia- New Guinea, New Guinea-Southwest Coast, Merauke to Tanjung Van Den Bosch. 3rd ed. 1996, scale 1 : l,OOO,OOO. Chart No. 74008, Australia-Indonesia-, Booby Island to Wessel including Gulf of Carpentaria. 6th ed. 1994, scale 1 : l,OOO,OOO. Chart No. 92006, Asia, Philippines Islands, Southern Part Including Adjacent Islands and North Coast of Borneo. 5th ed. 1999, scale 1 : 1,089,900. Chart No. 92550, Philippine Islands, North Balabac Strait and vicinity. 2nd ed. 1976, scale 1 : 100,000. Chart No. 93036, Mui to ShenQuan Gang including Hainan Dao and . 10th ed. 1996, scale 1 : 1,035,OOO. Chart No. 93160, Gulf of Thailand-South China Sea, Thailand-Malaysia, to Laem Kho Thra, 3rd ed. 1986, scale 1 : 242,900. Chart No. 93180, Asia, Gulf of Thailand, Laem Kho Phra to Ko Kra, 7th ed. 1996, scale 1 : 250,000. Chart No. 93220, Asia, Gulf of Thailand, Lang Suan Roads to Prachuap Khiri Khan, 6th ed. 1997, scale 1 : 240,000. Chart No. 93280, Asia, Cambodia-Thailand, Gulf of Thailand, Ko Kut tq Baie De Ram, 4th ed. 1985, scale 1 : 240,000. Chart No. 94040, Shibeishan Jiao to Jiangjun Tou including Taiwan Banks. 13th ed. 1997, scale 1 : 300,000. Chart No. 94060, Haitan Wan to Gulei Tou including Adjacent Coast of T’ai-wan. 10th ed. 1996, scale 1 : 300,000.

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