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We describe two large predators from the hominoid-bearing Khorat sand pits, Nakhon Ratchasima Province, northeastern Thailand: a new genus of pantherine, Pachypanthera n. gen., represented by partial mandible and maxilla and an indeterminate sabre-toothed cat, represented by a fragment of upper canine. The morphological characters of Pachypanthera n. gen., notably the large and powerful canine, the great robustness of the mandibular body, the very deep fossa for the m. masseter, the zigzag HSB enamel pattern, indicate bone-cracking capacities. The genus is unique among Felidae as it has one of the most powerful and robust mandibles ever found. Moreover, it may be the oldest known pantherine, as other Asian pantherines are dated back to the early Pliocene. The taxa we report here are the only carnivorans known from the late Miocene of Thailand. Although the material is rather scarce, it brings new insights to the evolutionary history of Neogene mammals of Southeast Asia, in a geographic place which is partly "terra incognita."

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The evolutionary history and palaeoecology of orangutans remains poorly understood until today. The restricted geographic distribution of extant Pongo indicates specific ecological needs. However, it is not clear whether these needs were shared by the great diversity of fossil pongines known from the Miocene to the Pleistocene. Here we show how niche modelling of stable carbon and oxygen isotope data of the carbonate fraction of dental enamel can be used to reconstruct the paleoecology of fossil and modern pongines and associated mammal communities. We focus on Khoratpithecus ayeyarwadyensis, a Late Miocene pongine from Myanmar and the sister clade to extant orangutans, and compare it to its associated mammal fauna and other fossil and extant pongines. The results are consistent with a vertical position high up in the canopy of a forested habitat with purely C3 vegetation for K. ayeyarwadyensis as well as the contemporaneous Sivapithecus. Although their positions in the modelled isotopic niche space look similar to the ecological niche occupied by modern Pongo, a comparison of the modelled niches within the pongine clade revealed possible differences in the use of microhabitats by the Miocene apes.

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Since their discovery in 1927, the phylogenetic status of the Myanmar amphipithecines has been highly debated. These fossil primates are recognized either as anthropoids or as adapiform strepsirrhines. This uncertainty was largely the consequence of a limited fossil record consisting mostly of jaw fragments but lacking the critical cranial elements that might resolve this debate. We report here cranial remains associated with an ulna from a single individual pertaining to the amphipithecine Ganlea megacanina. In addition to anthropoid-like dentognathic characters, Ganlea displays several ulna and skull features that testify to its anthropoid affinities (e.g. short subvertically oriented lacrimal duct, lacrimal foramen and bone inside the orbit, maxillary contribution to the lower orbital rim, fused metopic suture). By contrast to crown anthropoids, however, Ganlea lacks postorbital closure, confirming that postorbital closure appeared later than many anthropoid dentognathic characters and evolved convergently in extant tarsiers and anthropoids. Thus, amphipithecines must now be recognized as stem anthropoids offering a unique window on the early evolution of cranial and skeletal features in anthropoids, and reinforcing the hypothesis of an origin and early diversification of anthropoids in Asia.

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The strong present-day Asian monsoons are thought to have originated between 25 and 22 million years (Myr) ago, driven by Tibetan-Himalayan uplift. However, the existence of older Asian monsoons and their response to enhanced greenhouse conditions such as those in the Eocene period (55-34 Myr ago) are unknown because of the paucity of well-dated records. Here we show late Eocene climate records revealing marked monsoon-like patterns in rainfall and wind south and north of the Tibetan-Himalayan orogen. This is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from Myanmar, and by aeolian dust deposition in northwest China. Our climate simulations support modern-like Eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhanced greenhouse conditions counterbalanced the negative effect of lower Tibetan relief on precipitation. These strong monsoons later weakened with the global shift to icehouse conditions 34 Myr ago.

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Although Asia is thought to have played a critical role in the basal radiation of Ruminantia, the fossil record of early selenodont artiodactyls remains poorly documented in this region. Dental remains of a new bunoselenodont artiodactyl are described from the late Eocene of Krabi, southern Thailand. This new form, Krabitherium waileki gen. et sp. nov, is tentatively referred to the Tragulidae (Ruminantia) on the basis of several dental features, including a weak Tragulus fold and the presence of a deep groove on the anterior face of the entoconid. Although this new form is suggestive of the enigmatic? Gelocus gajensis Pilgrim 1912 from the "base of the Gaj" (lower Chitarwata Formation) of the Bugti Hills (Central Pakistan), K. waileki most likely represents an early representative of a relatively bunodont group of tragulids that includes the genus Dorcabune, known from the Miocene of south Asia. This addition to the Eocene record of early ruminants attests to the antiquity of the group in Southeast Asia and lends support to the hypothesis that the Tragulidae represents one of the first offshoots in the evolutionary history of Ruminantia.

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In the absence of a comprehensive fossil record, the origin and early evolution of Malagasy lemurs have been subject to much uncertainty. We report here the discovery of a strepsirrhine fossil with strong cheirogaleid lemur affinities, Bugtilemur mathesoni gen. et sp. nov., from early Oligocene deposits of the Bugti Hills (Balochistan, Pakistan). Bugtilemur represents the earliest record of Lemuriformes, which hence appear to have already diversified outside of Madagascar at least 30 million years ago. This fossil clearly enhances the critical role of the Indian subcontinent in the early diversification of lemurs and constrains paleobiogeographic models of strepsirrhine lemur evolution.

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We describe here a nearly complete lower jaw of Siamopithecus eocaenus from the Late Eocene of Peninsular Thailand. It displays several new characters, such as the symphysis, the horizontal branch, part of the vertical branch and most of its anterior dentition. The symphysis is nearly vertical and bears most characteristics of that of derived anthropoids but is unfused. Incisors were not preserved. A large canine, P/2 alveolus and P/3-M/3 were preserved. P/2 is rooted and reduced. The morphology of P/3 and P/4 is characteristic of that of anthropoids, with an oblique position in the tooth row, a labially displaced anterior root of P/3 and P/4 and the presence of a lingually developed metaconid on P/4. The premolars display a primitive stage of anthropoid evolution. This discovery confirms the anthropoid status of Siamopithecus, its attribution to the family Amphipithecidae and demonstrates the importance of Asia in the evolution of anthropoid primates.

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Pondaungia cotteri is the largest primate known from the Late Middle Eocene Pondaung Formation, Myanmar. Its taxonomic status has been the subject of much debate because of the fragmentary nature of its remains. Initially described as an anthropoid, some authors recently have associated it with adapid primates. These debates have been fueled not only by the incompleteness of the fossils attributed to Pondaungia but also by the reticence of many authors to regard Asia as an important evolutionary theater for Eocene anthropoids. During the November 1998 Myanmar-French Pondaung Expedition, a right lower jaw was discovered that yields the most nearly complete dentition of Pondaungia cotteri ever found: it shows the complete horizontal ramus, alveoli for the second incisor and canine, three premolars, and three molars. The symphysis showed all characteristics of anthropoids but was unfused. The canine root is large, the first premolar is absent, and the second premolar is single-rooted, reduced, and oblique in the tooth row, as in anthropoids. The premolars show a reduced mesio-distal length compared with the tooth row, and their morphology is very similar to that of Amphipithecus mogaungensis. Therefore, the two Pondaung taxa appear to be closely related to each other, with Siamopithecus as their sister taxon.

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The origin and evolution of hominoid primates (apes and man) has long been studied exclusively on the basis of available fossil remains. Indeed, a migration of African primates towards Asia at about -16 to -17 Ma might have given the lineage of Miocene Asian hominoids. This hypothesis is supported by the oldest remains of Miocene Asian hominoids dated at about -16.1 Ma. But the recent discovery of anthropoid primates in the Eocene of Asia seems to indicate that Asia was a major evolutionary and differentiation centre for anthropoid primates as early as the Eocene. In addition, Asian primates probably continued to evolve in Asia from the Eocene onward and led at least to the extant Asian hominoids (orangutans and gibbons). African and Asian extant anthropoid primates might therefore have diverged at least 36 Ma ago, and this hypothesis is also supported by the most recent data in molecular biology. Moreover, an Asiatic origin of African Paleogene propliopithecine primates is suggested. In that context, evolutionary rates might not be constant, and molecular clocks should be necessarily characteristic for each studied group of mammals. Several examples that illustrate the conflict between paleontological and molecular data are discussed. The necessity to integrate more systematically paleontological data as chronological reference points in studies in molecular phylogeny is discussed.

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Do the brains of men and women show similar patterns of functional organization for language, or are men more strongly lateralized? We used PET to measure cerebral blood flow (CBF) as men and women read real and nonce verbs, and produced past tense forms. While the overall patterns of reaction time, error, and brain activation were similar, there were also significant sex-related differences in CBF patterns. During the past tense generation tasks, men showed left-lateralized activation while women recruited bilateral perisylvian cortex, confirming differences in functional laterality. During all tasks, women showed higher activation in occipital and/or cerebellar regions, suggesting differences in basic reading strategies. We conclude that sex differences in functional cortical organization exist in the absence of significant behavioral differences.

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In the context of a Thai-French paleontological project, a single human tooth, a right upper fourth premolar, has been discovered in Northern Thailand among mammalian fossil remains excavated from the "Thum Wiman Nakin" cave. Based on the fauna associated with the human tooth and the Uranium/Thorium datings from the overlying calcite beds, we attribute this site to the Late Middle Pleistocene. The human tooth was compared with teeth of Chinese and Javanese Homo erectus, Homo sapiens neanderthalensis and Homo sapiens sapiens as well as teeth of apes (Orang-utan). The tooth has archaic features of the crown which are similar to Homo erectus. It also has derived features of the root which makes it aligns with Neanderthals and modern humans. Consequently, it has been tentatively attributed to Homo sp. Homo remains have not been previously reported from Thailand, and the specimen described here is therefore the first and oldest fossil human remain from this country.

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While the neuropsychological literature includes few cases of child-onset amnesia, 2 previous case studies suggest that these patients may be able to learn new information of a semantic or academic nature. The previous studies were, in large part, based on neuropsychological testing performed during adulthood and a retrospective review of academic achievement test scores during childhood. We present patient A.C., who acquired severe anterograde amnesia at age 10 years but demonstrated average levels of performance on tests of reading, spelling and arithmetic upon examination at age 19 years. Episodic and semantic memory test scores were severely impaired, but near normal performances were found on tests of implicit and procedural memory. In a prospective study, A.C. learned to read new irregular and pseudowords and retained this learning over a 1-month period, similar to the performance of age-matched controls. This demonstration of postmorbid, acquired oral reading vocabulary supports a previous conclusion that oral reading can progress in childhood following the onset of severe anterograde amnesia. The data also suggest that this new learning probably reflects nondeclarative memory processes rather than preservation of semantic memory, as was proposed in an earlier case study.

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The fossil record of anthropoid primates from the Middle Eocene of South Asia is so far restricted to two genera (Pondaungia cotteri Pilgrim, 1937 and Amphipithecus mogaungensis Colbert, 1937 from the Eocene Pondaung deposits of Burma) whose anthropoid status and phylogenetic position have long been under debate because they represent the oldest highly derived fossil primates of anthropoid grade. Moreover, several new African taxa, some of which are even older, have been recently included in the suborder Anthropoidea, suggesting an African origin for this group. Conversely, new fossil primates recently discovered in China (Eosimias) have been related to the most primitive representatives of Anthropoidea, alternatively suggesting an Asian origin and a probable Asian radiation centre. We report here the discovery of a new anthropoid from the Thai Late Eocene locality of Krabi, which displays several additional anthropoid characters with regard to those of the Eocene Burmese genera. This species, which is about the size of the Fayum Aegyptopithecus, can be related to the Burmese forms, and it further provides strong additional evidence for a southeast Asian evolutionary centre for anthropoids.

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A well preserved mouse skull has been recovered from a pedogenically modified mudstone layer (c. 2 millions years (MY) old) of Pinjor Formation (Upper Siwaliks) exposed east of Chandigarh, India. Comparison of the present skull with those of the extant species of the subgenus Mus reveals its closer relationship towards the house mouse Mus musculus lineage. The present fossil evidence is very much in line with the molecular, allozymic and ecological proposals for the time and place of origin of the subgenus Mus.

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We identified inspired gas conditions that result in no net respiratory heat loss, an isenthalpic condition, but induce a mucosal loss of water. Inspired gas at 37 degrees C with 47 mm Hg water vapor pressure, 56 degrees C with 38 mm Hg; and 78 degrees C with 27 mm Hg has the same heat content as fully saturated air at body temperature. In four normal subjects hyperventilating at a minute ventilation of 30 times their FEV1 for 6 min, expired temperatures at the mouth averaged 39 degrees, 43 degrees, and 43 degrees C for the three conditions. Retrotracheal esophageal temperatures did not fall in any subject, thereby demonstrating the absence of significant airway cooling. Nine subjects with exercise-induced bronchospasm were tested under the same conditions. Baseline functions showed an FEV1 of 85 +/- 10% of predicted (mean +/- SD), FVC, 98 +/- 13% of predicted, and FEV1/FVC, 79 +/- 4% of predicted. The asthmatic subjects demonstrated postchallenge mean falls in FEV1 of 3.4%, 6.2%, and 10.1% for the three conditions, with bronchospasm increasing as the temperature of the inspired air increased (p = 0.001). The amount of respiratory water lost from the respiratory mucosa significantly correlated with the resultant bronchospastic response as measured by the fall in FEV1 (p = 0.017), but the net respiratory heat lost did not significantly correlate (p = 0.113). This study demonstrates that bronchospasm can be induced without significant respiratory heat loss or airway cooling and suggests that it is proportional to the amount of water lost from mucosal surfaces.

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Spiny mice of the genus Acomys traditionally have been classified as members of the Murinae, a subfamily of rodents that also includes rats and mice with which spiny mice share a complex set of morphological characters, including a unique molar pattern. The origin and evolution of this molar pattern, documented by many fossils from Southern Asia, support the hypothesis of the monophyly of Acomys and all other Murinae. This view has been challenged by immunological studies that have suggested that Acomys is as distantly related to mice (Mus) as are other subfamilies (e.g., hamsters: Cricetinae) of the muroid rodents. We present molecular evidence derived from DNA.DNA hybridization data that indicate that the spiny mouse Acomys and two African genera of Murinae, Uranomys and Lophuromys, constitute a monophyletic clade, a view that was recently suggested on the basis of dental characters. However, our DNA.DNA hybridization data also indicate that the spiny mice (Acomys) are more closely related to gerbils (Gerbillinae) than to the true mice and rats (Murinae) with which they have been classified. Because Acomys and the brush-furred mice Uranomys and Lophuromys share no derived morphological characters with the Gerbillinae, their murine morphology must have evolved by convergence, including the molar pattern previously considered to support the monophyly of the Murinae.

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Young children's slips of the tongue are a rich source of information about developing language processing and storage mechanisms. This paper presents an analysis of 907 slips from 32 children, ages 1;4-6;0, collected in naturalistic settings. It is found that these children make most of the same types and proportions of slips as adults: phonological errors outnumber lexical, which exceed phrasal. In phonological errors, anticipations are most common, followed by perseverations and exchanges; children make more completed anticipations and exchanges than adults, probably due to less mature self-monitoring. Like adults, children make more substitutions than additions or omissions. Children's slips support a theory of speech planning in which propositional, syntactic, intonational, content word, function word and phonological levels have somewhat independent status; however, there is little evidence for a derivational morphology level at this age.

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The form in which phonological information is stored in the lexical entries of young children, and how this form changes over time, are questions which are difficult to address, given the limitations of current methodologies. However, slips of the tongue made by young children can be used to shed some light on the question. Earlier research (Stemberger, 1989; Jaeger, 1992) has shown that children as young as 1;7 (one year seven months) make slips in which single consonants or single vowels are substituted or exchanged, implying segmental organization in phonological representations. In the present paper, a corpus of 366 consonant substitutions and reversals made by young children, aged 1;7-6;0, are subjected to a multidimensional scaling analysis, and are shown to be governed by patterns of phonetic similarity, indicating that these segments have phonetic structure. A feature system based on the scaling procedure is found to be somewhat different from one generated by van den Broecke and Goldstein (1980) from adult errors, especially in manner features. While both adults and children err on the 'place of articulation' feature most often, and 'nasality' least often, children produce 'voicing' feature errors less often than adults do, indicating that voicing may be a more important organizing principle for young children than for adults. Some age-related trends in number and type of feature errors are discussed.

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The Muroidea, a group of rodents that includes mice, rats, gerbils, hamsters and others, encompasses a tremendous diversity of fairly recent geological origin. The taxonomy, systematics, phylogeny and paleontology of the muroid rodents have progressed enormously during the last two decades, and many hypotheses on their evolutionary biology have been formalized. Nevertheless, there still remain important unanswered questions - regarding, for example, local conflicts between molecular and paleontological data, or the origin of the fast rate of DNA change in rats and mice - that need more investigation.

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Physostigmine, as a pretreatment candidate for nerve agent poisoning, was examined for cardiopulmonary side effects. Cardiovascular and pulmonary parameters were monitored in unanesthetized domestic pigs which received pulmonary arterial infusion of 5 micrograms/kg/min physostigmine salicylate for 2 hr. A level of 74% inhibition of red blood cell (RBC) acetylcholinesterase (AChE) activity was attained in 45 min, and this level of carbamylation increased only slightly during the remaining infusion period. In addition to this large change in AChE activity, minor changes were observed in hematocrit, heart rate, body temperature, mean aortic pressure, pulmonary arterial wedge pressure, and pulmonary artery pressure. Typically, these parameters showed a trend toward elevated levels. Blood gases, pH, respiratory rate, tidal and minute volume, cardiac output, nonelastic resistance, and dynamic compliance were not significantly different from baseline values. The unanesthetized pig responds to physostigmine in a manner similar to that reported for other species and appears to be a suitable model for evaluating cardiopulmonary effects of cholinesterase inhibitors.

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