There are sites in Southeast Asia, both mainland and island, and layers within sites, within the time range of the Hoabinhian that do not include Hoabinhian artifacts. It is necessary to consider this evidence, not only in its own right, but to shed further light on the Hoabinhian itself. If there was indeed a Hoabinhian culture, does that mean that sites/layers which lack Hoabinhian tools represent some other culture? This evidence has generally been perceived as representing a mass of problematic data, nondescript at best, incoherent and unclassifiable at worst, and completely unrelated to the Hoabinhian.
While it may be undistinguished compared with the neat types of the European Palaeolithic, these stone industries are not quite the morass of indistinguishable characteristics as has been represented. Not only in island Southeast Asia, but also at some sites on the mainland, there is a technological similarity among Upper Pleistocene industries. At many sites, assemblages consist of small, apparently casual flakes, in a range of lithologies, often including reef quartz and fine-grained chert and silcrete types. Flakes tend towards the square rather than the elongated. While simple percussion is the main flaking technique found, the bipolar technique is often in evidence, and flakes with secondary working are rare, but do occasionally appear. These assemblages are similar to those found in Chinese sites, some of which are up to 1 million years old (such as sites in the Nihewan basin), and include Zhoukoudian, and are thus associated with H. erectus. They are also found at Chinese sites within the age range of H. sapiens.
This range of small-undistinguished artifacts appears at first glance to be quite different from the Hoabinhian industry. It is not however a completely different technology. The kind of percussion flaking which produces a Hoabinhian core artifact also produces flakes which share metrical and qualitative characteristics with the other industry or industries. In Australia, within the delimited space of Kangaroo Island, off the coast near Adelaide, it has been shown that Hoabinhian artifacts are in fact part of a wider industry including just such small artifacts as described here, even though the Hoabinhian types tend not to be found at the same sites as the smaller artifacts. This also seems to be the case in Southeast Asia, although there are some sites in Thailand and Vietnam where the smaller artifacts are found with the Hoabinhian types; generally the former have been overlooked and not remarked on when the sites were described. Sites yielding only the small ‘amorphous’ assemblages are known from island Southeast Asia, for example Leang Burung 2 in Sulawesi and Liang Lembudu in the Aru Islands, dating to 31 000 and 27 000 years ago, respectively.
There are some sites which do not fit the pattern so far described. Tingkayu, an open site, or rather series of sites, in Sabah on the island of Borneo, has a range of rather elegant ‘bifacial lanceolates’, which are quite outside the range of most assemblages from
Late Pleistocene sites in Southeast Asia. The chronology of this site complex is far from secure however, consisting as it does of open sites dated by geomorphological circumstances, and the age of these objects must be considered unproven.
There have been attempts to demonstrate a sequence of artifact change over the course of the Late Pleistocene. The site of Lang Rongrien in peninsular Thailand has been recently excavated using modern techniques, and has produced a noncontinuous sequence from c. 37 000 years ago to Holocene agricultural times. It has been interpreted as evidence of change from a small nondescript industry dated to between c. 37 000 and 27 000 years ago to a Hoabinhian industry appearing in terminal Early Holocene times, dating to between c. 9500 and 7500 years ago. This is not a classic Hoabinhian assemblage however, but consists of the bifacially flaked types also characterized as Hoabinhian in peninsular Malaysia. In Malaysia, these types are generally dated to a similar time range; types with more typical unifacial Hoabinhian types are in fact rather older in both Malaysia and Thailand.
It seems however that obvious cultural change, consisting of new stone artifact types, did not occur until the Holocene. A range of small tools including backed blades and small projectile points are found in sites dated to after 7000 years ago in island Southeast Asia, notably Sulawesi and the Philippines. The Toalian assemblages of asymmetric and geometric microliths from southwestern Sulawesi have been known since the early twentieth century, and their appearance has been subsequently dated to about 6000 years ago. In the Philippines, serrated hollow-based points called Maros points have been within the same time frame. It seems that in both cases, the new tools were associated with hunter-gatherers who kept on using them when they took up agriculture.