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A new fossil site in a previously unexplored part of western Madagascar (the Beanka Protected Area) has yielded remains of many recently extinct vertebrates, including giant lemurs (Babakotia radofilai, Palaeopropithecus kelyus, Pachylemur sp., and Archaeolemur edwardsi), carnivores (Cryptoprocta spelea), the aardvark-like Plesiorycteropus sp., and giant ground cuckoos (Coua). Many of these represent considerable range extensions. Extant species that were extirpated from the region (e.g., Prolemur simus) are also present. Calibrated radiocarbon ages for 10 bones from extinct primates span the last three millennia. The largely undisturbed taphonomy of bone deposits supports the interpretation that many specimens fell in from a rock ledge above the entrance. Some primates and other mammals may have been prey items of avian predators, but human predation is also evident. Strontium isotope ratios (87Sr/86Sr) suggest that fossils were local to the area. Pottery sherds and bones of extinct and extant vertebrates with cut and chop marks indicate human activity in previous centuries. Scarcity of charcoal and human artifacts suggests only occasional visitation to the site by humans. The fossil assemblage from this site is unusual in that, while it contains many sloth lemurs, it lacks ratites, hippopotami, and crocodiles typical of nearly all other Holocene subfossil sites on Madagascar., Research at Beanka was supported by the National Geographic Society via Waitt Foundation grants W263-13 and W388-15 to DAB, and by the site-managing organization, Biodiversity Conservation Madagascar (BCM). EJdB was supported by a travel grant from the Society for Advancement of Research in the Tropics (Treub Maatschappij). The scientific study authorization was provided by the Bureau du Cadastre Minier de Madagascar with the reference 024/2015. Many thanks to faculty of the Université d'Antananarivo and staff of BCM and Association Vahatra for assistance with permits and logistics. To the staff of BCM and the people of the village of Ambinda, we extend special thanks for hospitality and assistance with fieldwork and information regarding sites and access. Bone specimens were identified from studies of comparative materials at the Field Museum of Natural History, the Université d'Antananarivo, Association Vahatra, Duke Lemur Center, Muséum national d'Histoire naturelle (Paris), the Natural History Museum (London), the Smithsonian Institution, the American Museum of Natural History, and the University of Massachusetts, Amherst. Species identifications were supported in part by NSF BCS-1750598 (to LRG). Isotopic and radiocarbon analyses were supported in part by NSF BCS-1749676 (to BEC).

At Makauwahi Cave Reserve, on the south shore of Kaua`i, translocation decisions have been guided to a unique degree by the richly detailed fossil record of biota of recent centuries, which occurs on the site. To evaluate the efficacy of this strategy, ecological conditions and individual life histories for 3388 translocated native plants of 81 species have been monitored since 2005. Many species were selected on the basis of their prevalence as subfossils in the adjacent late Holocene cave sediments. Most of these species no longer occur on or near the abandoned farmlands and mine spoil used as a substrate for transplanted individuals. Records for each plant included location, date outplanted, flowering, fruiting, and, if applicable, mortality, including known or inferred cause. Also recorded was unaided recruitment, survival of transplanted recruits, and quantity of seed collected. Plant species selected for reintroduction on the basis of present occurrence near the site (many of which also occur there as fossils), and species not present but selected solely on the basis of fossil occurrence before European arrival, both show high survival rates in most cases. Species that fit neither of these criteria, but are judged suitable on the basis of their occurrence elsewhere on the island in similar habitats, generally showed lower survival rates. Primary mortality factors for nursery stock not surviving outplanting included transplant shock, irrigation failure, and human error (accidental cutting, pulling, or trampling). Much lower mortality rates were linked to insect damage, disease, and pig disturbance. Phenological records show that 80 % of translocated native species have flowered and 70 % produced seed. Unaided recruitment was observed for 43 % of the species with some rare species producing large numbers of volunteer seedlings. Translocated volunteer seedlings showed high survival rates. Insights from the fossil record have provided perspective on the site’s potential and limitations and enriched interest in a restoration by almost doubling the list of plant species used in restoration programs and adding a living history element to the interpretation of the site through the juxtaposition of the fossil evidence and the translocated native species.

Humans now play a major role in altering Earth and its biota. Finding ways to ameliorate human impacts on biodiversity and to sustain and restore the ecosystem services on which we depend is a grand scientific and societal challenge. Conservation paleobiology is an emerging discipline that uses geohistorical data to meet these challenges by developing and testing models of how biota respond to environmental stressors. Here we (a) describe how the discipline has already provided insights about biotic responses to key environmental stressors, (b) outline research aimed at disentangling the effects of multiple stressors, (c) provide examples of deliverables for managers and policy makers, and (d) identify methodological advances in geohistorical analysis that will foster the next major breakthroughs in conservation outcomes. We highlight cases for which exclusive reliance on observations of living biota may lead researchers to erroneous conclusions about the nature and magnitude of biotic change, vulnerability, and resilience.

A new species of shrew tenrec, Microgale macpheei ,i s described from subfossil deposits in Andrahomana Cave, extreme southeastern Madagascar. This species is distinguished from all named taxa of Microgale by a variety of osteological, dental, and mensural characters. It is presumed to be the sister taxon to the extant species M. brevicaudata, which is not known to occur in southeastern Madagascar. Although the genus contains well over 20 living species, M. macpheei is the first known extinct shrew tenrec in the Quaternary fauna of Madagascar. Resume ´.—Une nouvelle espece de microgale,Microgale macpheei, trouvee dans les depots subfossiles de la grotte d'Andrahomana, dans l'extreme sud de Madagascar, est decrite. Cette espece se distingue de tous les taxons nommes dans ce genre par divers caracteres portant sur l'osteologie, la dentition et les mesures. Elle semble montrer des affinites avec l'espece actuelle M. brevicaudata qui n'est pas connue du sud-est de Madagascar. Bien que le genre soit representepar bien plus de 20 especes vivantes, la description de M. macpheei constitue la premiere e d'un microgale e dans la faune du Quaternaire de Madagascar.

Paleoecological studies from tropical islands around the globe show that human colonization has been devastating for these remote biotic communities. Island histories reveal that human predation and human-mediated landscape change have each played a key role, but many island extinctions following human arrival are strongly associated with introduced predators, herbivores, weeds, and diseases. On the Hawaiian Island of Kaua'i, human-caused extinctions are currently occurring in a microcosm of island endemics. Recent studies of endangered plants suggest that conventional in-situ and ex-situ conservation strategies are losing the battle here. Paleoecological findings support the idea that creating new populations in formerly much larger, late prehistoric and early historical ranges of declining species may provide a reliable and cost-effective hedge against extinction. On Kaua'i, several paleoecological sites have played key roles in planning and implementing ecological and cultural restoration projects.

Remains of a large-bodied species of endemic nesomyid rodent, Macrotarsomys petteri Goodman and Soarimalala, 2005, were identified from subfossil deposits recovered from Andrahomana Cave in extreme southeastern Madagascar. This recently described extant species was previously only known from a single specimen collected at a site about 450 km northwest of Andrahomana and with distinctly different forest habitat than currently found in the vicinity of the cave. Radiocarbon dating of remains of M. petteri from the cave site indicates that it persisted in the region subsequent to human settlement. Previous reports of a large member of Macrotarsomys from other Quaternary sites in southern Madagascar are almost certainly of M. petteri. It is proposed that this species once had a broad distribution across the southern portion of the island during a more mesic period and subsequent aridification of the region has led to its local extirpation across most of its former range. To cite this article: S.M. Goodman et al., C. R. Palevol 5 (2006).

Large vertebrates are strong interactors in food webs, yet they were lost from most ecosystems after the dispersal of modern humans from Africa and Eurasia. We call for restoration of missing ecological functions and evolutionary potential of lost North American megafauna using extant conspecifics and related taxa. We refer to this restoration as Pleistocene rewilding; it is conceived as carefully managed ecosystem manipulations whereby costs and benefits are objectively addressed on a case-by-case and locality-by-locality basis. Pleistocene rewilding would deliberately promote large, long-lived species over pest and weed assemblages, facilitate the persistence and ecological effectiveness of megafauna on a global scale, and broaden the underlying premise of conservation from managing extinction to encompass restoring ecological and evolutionary processes. Pleistocene rewilding can begin immediately with species such as Bolson tortoises and feral horses and continue through the coming decades with elephants and Holarctic lions. Our exemplar taxa would contribute biological, economic, and cultural benefits to North America. Owners of large tracts of private land in the central and western United States could be the first to implement this restoration. Risks of Pleistocene rewilding include the possibility of altered disease ecology and associated human health implications, as well as unexpected ecological and sociopolitical consequences of reintroductions. Establishment of programs to monitor suites of species interactions and their consequences for biodiversity and ecosystem health will be a significant challenge. Secure fencing would be a major economic cost, and social challenges will include acceptance of predation as an overriding natural process and the incorporation of pre-Columbian ecological frameworks into conservation strategies.

Remains of what appears to be a single, subadult Hadropithecus stenognathus were recovered from a previously unexcavated site at Andrahomana Cave (southeastern Madagascar). Specimens found comprise isolated teeth and cranial fragments (including the frontal processes of the orbits), as well as a partial postcranial skeleton. They include the first associated fore- and hind-limb bones, confirming the hind-limb attributions made by Godfrey and co-workers in 1997, and refuting earlier attributions by Lamberton in 1937/1938. Of particular interest here are the previously unknown elements, including a sacrum, other vertebrae and ribs, some hand bones, and the distal epiphysis of a femur. We briefly discuss the functional implications of previously unknown elements. Hadropithecus displayed a combination of characters reminiscent of lemurids, others more like those of the larger-bodied Old World monkeys, and still others more like those of African apes. Yet other characteristics appear unique. Lemurid-like postcranial characteristics may be primitive for the Archaeolemuridae. Hadropithecus diverges from the Lemuridae in the direction of Archaeolemur, but more extremely so. Thus, for example, it exhibits a stronger reduction in the size of the hamulus of the hamate, greater anteroposterior compression of the femoral shaft, and greater asymmetry of the femoral condyles. Nothing in its postcranial anatomy signals a close relationship to either the Indriidae or the Palaeopropithecidae.

A cave system in the eolianite deposits of the Māhā′ulepū/Pā′ā area of Kaua′i, Hawai′i, contains a rich fossil record of prehuman Holocene conditions and also preserves a thousand-year record of human activity. Details concerning pre-Contact Polynesian life have been extracted from subaqueous middens and artifacts, including perishable materials such as wood, gourd, and cordage. Oral traditions concerning the cave and vicinity generally show good agreement with the archaeological and paleoecological record and provide rich stories said to derive from as early as the fourteenth century A.D. Fossil evidence highlights biotic and landscape changes before, during, and after initial Polynesian and subsequent European settlement. The approximate temporal coincidence of evidence for human arrival and last occurrence of some now-extinct species is too great to ignore the possibility that humans played a role in some extinctions of native taxa before European colonization. Old maps, an 1824 sketch, records of the Land Court Awards, and old photographs confirm stratigraphic inferences and oral accounts concerning demographic and ecological conditions of the early historical period. Feral livestock proliferated in the nineteenth and early twentieth centuries, with loss of vegetative cover to overgrazing, decline of most of the native flora, and subsequent dune reactivation. Sedimentation rates reach their peak later in the twentieth century after the establishment of agricultural and mining operations nearby.

Modern tools of paleoecological and ecomorphological research have enabled researchers to reconstruct the lifeways of extinct species more thoroughly than ever before. We apply a variety of tools in an attempt to reconstruct the diets of the extinct archaeolemurids of Madagascar. Our data include dental use wear (examined across species and across ontogenetic series of single species), enamel microstructure, enamel thickness, and δ13C. The data are complemented by field data on the environmental contexts in which the species lived and 14C determinations that demonstrate the surprisingly late survival of archaeolemurids. Several lines of evidence converge to suggest that all archaeolemurid species were hard-object processors, but with different diets and different methods of food processing. Past reconstructions of the diet of Hadropithecus as a specialized grass consumer fail under the scrutiny of multiple lines of evidence.

Stratigraphic palynological analyses of four late Quaternary deposits com- prise a landscape-level study of the patterns and processes of megafaunal extinction in southeastern New York State. Distinctive spores of the dung fungus Sporormiella are used as a proxy for megafaunal biomass, and charcoal particle analysis as a proxy for fire history. A decline in spore values at all sites is closely followed by a stratigraphic charcoal rise. It is inferred that the regional collapse of a megaherbivory regime was followed by landscape transformation by humans. Correlation with the pollen stratigraphy indicates these devel- opments began many centuries in advance of the Younger Dryas climatic reversal at the end of the Pleistocene. However, throughout the region, the latest bone collagen dates for Mammut are considerably later, suggesting that megaherbivores lasted until the beginning of the Younger Dryas, well after initial population collapse. This evidence is consistent with the interpretation that rapid overkill on the part of humans initiated the extinction process. Landscape transformation and climate change then may have contributed to a cascade of effects that culminated in the demise of all the largest members of North America's mammal fauna.

Recent expeditions to Madagascar have recovered abundant skeletal remains of Archaeolemur, one of the so-called “monkey lemurs” known from Holocene deposits scattered across the island. These new skeletons are sufficiently complete to permit reassembly of entire hands and feet—postcranial elements crucial to drawing inferences about substrate preferences and positional behavior. Univariate and multivariate analysis of intrinsic hand and foot proportions, phalangeal indices, relative pollex and hallux lengths, phalangeal curvature, and distal phalangeal shape reveal a highly derived and unique morphology for an extinct strepsirrhine that diverges dramatically from that of living lemurs and converges in some respects on that of Old World monkeys (e.g., mandrills, but not baboons or geladas). The hands and feet of Archaeolemur are relatively short (extremely so relative to body size); the carpus and tarsus are both “long” relative to total hand and foot lengths, respectively; phalangeal indices of both the hands and feet are low; both pollex and hallux are reduced; the apical tufts of the distal phalanges are very broad; and the proximal phalanges are slightly curved (but more so than in baboons). Overall grasping capabilities may have been compromised to some extent, and dexterous handling of small objects seems improbable. Deliberate and noncursorial quadrupedalism was most likely practiced on both the ground and in the trees. A flexible locomotor repertoire in conjunction with a eurytopic trophic adaptation allowed Archaeolemur to inhabit much of Madagascar and may explain why it was one of the latest surviving subfossil lemurs.

Of all the things we have done to the Earth so far, which one is likely to make the most indelible mark? I have been posing this question to students and colleagues for some time, and usually receive one of three reasonable replies: habitat destruction, human overpopulation, or global climate change. Yet as bad as all these maladies are, they are, to some extent, reversible on time scales to which we can relate. The remedies for these problems, despite mammoth cultural and economic obstacles, can be visualized generally in terms of technology and scientific theory. Only the will is lacking. On longer geological and evolutionary time scales, most such human impacts, if corrected soon, would be mere blips, perturbations of the ecosphere that would leave only a few detectable traces in the fossil record a million years hence.

In the last 2000 years, changes on the island of Madagascar have resulted in the modification of key environments and the extinction of nearly all large native animals. Humans have long been suspected as the primary cause of this ecological catastrophe, but the exact mechanisms of the island's rapid transformation and the role of natural factors such as climate change remain uncertain. Caves in northwestern Madagascar are helping researchers to disentangle these factors, by providing many types of datable information concerning the past in close physical proximity. U-series dated pollen spectra from the caverns of Anjohibe provide a 40,000-year record of vegetation in the vicinity. Bone deposits from caves in the region provide new site records for extinct taxa, including Babakotia radofilai Godfrey et al. 1990, Plesiorycteropus madagascariensis Filhol 1895, and Mullerornis sp. Several extant taxa that were present in the region in the late Holocene are now locally extinct. Archaeological evidence from the caves suggests little or no human activity in the vicinity or interaction with the fauna at these sites until recent centuries.

None of the letters in response to Thomson et al. (1) undermine our conclusions. However, several issues have been raised, which we address in this reply. Beavan (2) dismisses some of the concerns that have been raised about the accuracy of the radiocarbon dates of the El Arenal-1 chicken bones, which are immediately pre-Columbian. Although procedures, such as ultrafiltration of amino acids, are common practice for suboptimal bone samples, such as the oldest El Arenal-1 sample, further complex issues, including dietary sources and the potential for indirect marine carbon input (3), mean that a detailed assessment of the site through multiple further dates would be required to exclude the possibility that the specimens might actually be post-Columbian. This approach seems particularly advisable given that analogous issues were raised about a surprisingly early date for New Zealand colonization based on Pacific rat bone dates …

The human colonization of Remote Oceania remains one of the great feats of exploration in history, proceeding east from Asia across the vast expanse of the Pacific Ocean. Human commensal and domesticated species were widely transported as part of this diaspora, possibly as far as South America. We sequenced mitochondrial control region DNA from 122 modern and 22 ancient chicken specimens from Polynesia and Island Southeast Asia and used these together with Bayesian modeling methods to examine the human dispersal of chickens across this area. We show that specific techniques are essential to remove contaminating modern DNA from experiments, which appear to have impacted previous studies of Pacific chickens. In contrast to previous reports, we find that all ancient specimens and a high proportion of the modern chickens possess a group of unique, closely related haplotypes found only in the Pacific. This group of haplotypes appears to represent the authentic founding mitochondrial DNA chicken lineages transported across the Pacific, and allows the early dispersal of chickens across Micronesia and Polynesia to be modeled. Importantly, chickens carrying this genetic signature persist on several Pacific islands at high frequencies, suggesting that the original Polynesian chicken lineages may still survive. No early South American chicken samples have been detected with the diagnostic Polynesian mtDNA haplotypes, arguing against reports that chickens provide evidence of Polynesian contact with pre-European South America. Two modern specimens from the Philippines carry haplotypes similar to the ancient Pacific samples, providing clues about a potential homeland for the Polynesian chicken.

Coring and excavations in a large sinkhole and cave system formed in an eolianite deposit on the south coast of Kaua‘i in the Hawaiian Islands reveal a fossil site with remarkable preservation and diversity of plant and animal remains. Radiocarbon dating and investigations of the sediments and their fossil contents, including diatoms, invertebrate shells, vertebrate bones, pollen, and plant macrofossils, provide a more complete picture of prehuman ecological conditions in the Hawaiian lowlands than has been previously available. The evidence confirms that a highly diverse prehuman landscape has been completely transformed, with the decline or extirpation of most native species and their replacement with introduced species. The stratigraphy documents many late Holocene extinctions, including previously undescribed species, and suggests that the pattern of extirpation for snails occurred in three temporal stages, corresponding to initial settlement, late prehistoric, and historic impacts. The site also records land-use changes of recent centuries, including evidence for deforestation, overgrazing, and soil erosion during the historic period, and biological invasion during both the Polynesian and historic periods. Human artifacts and midden materials demonstrate a high-density human presence near the site for the last four centuries. Earlier evidence for humans includes a bone of the prehistorically introduced Pacific rat (Rattus exulans) dating to 822 yr BP (calendar year [cal yr] AD 1039–1241). Vegetation at the site before human arrival consisted of a herbaceous component with strand plants and graminoids, and a woody component that included trees and shrubs now mostly restricted to a few higher, wetter, and less disturbed parts of the island. Efforts to restore lowland areas in the Hawaiian Islands must take into account the evidence from this study that the prehuman lowlands of dry leeward Kaua‘i included plants and animals previously known only in wetter and cooler habitats. Many species may be restricted to high elevations today primarily because these remote locations have, by virtue of their difficult topography and climate, resisted most human-induced changes more effectively than the coastal lowlands.

In July and August 1995, the authors interviewed elderly Malagasy with knowledge of the traditions and natural history of their home areas, centered on the villages of Belo-sur-mer, Antsira, and Ambararata, on the southwest coast of Madagascar. Several individuals related personal experiences in which they claim to have seen and heard animals that do not match any known extant animal of Madagascar. Two of the mystery animals, known locally as the kilopilopitsofy and kidoky, were described in terms similar to creatures detailed in historical accounts and folklore recorded in Madagascar between the mid-1600s and the end of the nineteenth century. The former of these has been compared by some authors to the dwarf hippopotamus and the latter to a giant lemur, animals generally inferred from radiocarbon dating of last known occurrences to have gone extinct early in the present millennium or perhaps a few centuries later. Stories by these same informants concerning extant animals demonstrate their accurate knowledge of the fauna. Magical powers are ascribed to some animals, such as the bokyboky, a viverrid (Mungotictis) that occurs in the region. Radiocarbon dates obtained recently on some of the extinct megafauna, showing that some extirpated taxa may have survived until recent centuries, confirm that ethnographic sources of information on these species should not automatically be dismissed as irrelevant or unreliable. [Madagascar, extinctions, megafauna, hippopotamus, lemur]

At least five species of large flightless waterfowl have become extinct in the Hawaiian Islands in recent millennia. These birds are thought to have occupied the role of large herbivores in a wide range of terrestrial habitats. A collection of coprolites from one of the species (Thambetochen chauliodous) was obtained during excavations in Holocene cave sediments on the island of Maui. The chemical composition and pollen and spore content of the coprolites are analysed and compared with pollen/spore spectra from the cave sediments and from recent goose scats. The results support the contention that these birds were primarily folivorous, and further suggest that ferns were important in the diet. The coprolites have a very fine texture that may result from efficient hindgut fermentation and digestion of plant fibre. Our data are discussed in the light of a recent hypothesis of plant/herbivore coevolution between extinct avian herbivores and native Hawaiian lobelias. The loss of large native herbivores, as well as other changes in vertebrate trophic structure due to extinctions over the past few thousand years, may still be affecting ecological processes in areas of the Hawaiian islands with native vegetation.

Inter-island paleoecological comparisons have provided useful information concerning the role of humans vs. background-level disturbance in tropical ecosystems. Major ecological changes have occurred since human arrival in Madagascar, the West Indies, the Hawaiian Islands, and elsewhere. Prehuman vegetation changes and disturbances have also been documented for many islands. Instructive inter-island similarities and differences have been detected in the chronology, distribution, and extent of human activities, vegetation changes, and biotic extinctions. The earliest stratigraphic proxy evidence for initial human impacts (including increased charcoal particle influx to sediments, first appearance of exotic pollen, increase in ruderal pollen, and paleolimnological evidence for cultural eutrophication of lake waters) generally confirm but sometimes predate the earliest conventional archaeological evidence for human activity. Carefully chosen sites permitting the close integration of palynological, paleontological, and archaeological data from a variety of island settings with differing geographic and historical contingencies can enable investigators to more fully evaluate the importance of a range of human and ecological variables in determining the overall character and dynamics of ecosystems.

International audience; The extinctions of keystone megafauna during the Pleistocene and Holocene continue to affect extant species and ecosystems. This is particularly acute in southern and western Madagascar where two now extinct species of giant tortoises were once amongst the most dominant herbivores. The extinct giant tortoises are likely to have influenced ecosystem processes by being effective dispersers of large seeds, keeping the understorey open, cycling nutrients, and indirectly regulating fire regimes. As a result of their extinction, ecological interactions and ecosystems have been altered. Given that there is evidence that the extant Aldabran giant tortoise, Aldabrachelys gigantea, is closely related to at least one of these Madagascan giant tortoises, Aldabrachelys abrupta, we propose using captive Aldabran giant tortoises to restore missing ecological functions. This ambitious approach will represent the first continental island restoration project with a surviving lineage of now extinct, endemic megafauna. Translocation of this megafauna species could be a pragmatic and cost-effective tool to contribute to halting the ongoing extinction processes in parts of western and southern Madagascar, and would further understanding of the role of these species in pre-human Madagascan ecosystems.

An extensive late Quaternary fauna, including many extinct giant lemurs, has been collected recently in a 110+-km system of caves in the Ankarana Massif of northern Madagascar. AMS 14C dates for the acid-insoluble (collagen/gelatin) fraction of bones of the giant lemur Megaladapis (26,150 ± 400 and 12,760 ± 70 yr B.P.) confirm its presence in the area during the late Pleistocene and provide the first Pleistocene 14 C ages from bones of the extinct megafauna of the island. The first date from bones of the recently described extinct Babakotia radofilai (4400 ± 60 yr B.P.) shows that it was present in northern Madagascar in mid-Holocene times. A comparatively recent age of 1020 ± 50 yr B.P. for the extinct Archaeolemur indicates survival of this genus for at least a millennium after the first direct evidence for humans in Madagascar. This suggests that the island's "extinction window" may have represented a longer time span than would have been expected under the Blitzkrieg model of late Quaternary extinctions. A mid-Holocene age (4560 ± 70 yr B.P.) for a bone sample of the small extant lemur Hapalemur simus indicates that the disappearance of this now-restricted species from the Ankarana occurred after this date. New data from the Ankarana and other sites on the island add to the consensus that major biotic changes occurred on Madagascar in the late Holocene.

Parmi les lemuriens existants, la reproduction lente n’est pas necessairement liee au ralentissement du developpement dentaire ou a l’acquisition ­tardive de l’independance. La variation du developpement dentaire est independante de la taille du corps des adultes. Les lemuriens existants different des anthropoides de meme taille dans leurs modeles de croissance et developpement (maturation dentaire precoce, petite taille a la naissance, sevrage precoce). Nos etudes sur la microstructure dentaire, la chronologie, et le changement du relief topographique des dents nous ont permis de tirer des conclusions sur les histoires de vie de lemuriens disparus. Le developpement dentaire de Hadropithecus stenognathus est semblable a celui des Hominoides, tandis que le developpement dentaire extremement rapide en a caracterise d’autres, meme de corps plus grand comme Palaeopropithecus. L’âge du sevrage est tres varie selon les especes. Nous avons estime l’intervalle entre des naissances successives de lemuriens geants, d’une maniere conservatrice, a deux ou trois ans. Cette diversite est correlee aux conditions environnementales. Certains Lemuriens disparus ont montre des convergences saisissantes avec les anthropoides de grande taille, en particulier des grands intervalles entre les naissances et des sevrages tardifs. C’etaient aussi les lemuriens avec le plus grand cerveau par rapport a la taille de leur corps.

Subfossil fecal pellets associated with Archaeolemur cf. edwardsi skeletal material from Anjohikely Cave in north-western Madagascar were probably derived from this large extinct lemur. Pellets were photographed, measured, and dissected. One of the pellets dates to 830 ± 60 years BP. Pellets contain a wide variety of items indicative of omnivory, including fibrous fruit exocarps and seeds; bat, rodent, frog, and lizard bone; gastropod shell; and crustacean and arthropod exoskeletons—all within a matrix of comminuted vegetation. Pollen contents from inside intact pellets support other paleoecological evidence that recent feeding had taken place in wooded grassland habitat. This diet is consistent with ethnohistorical data and anatomical studies that indicate hard-object feeding in Archaeolemur. Archaeolemur may have deliberately entered caves to forage, although caves would also have offered water, abundant shade, cool conditions, cryptic sleeping sites, and refuge from predators. Cave-exploring behavior is rare in primates, but consistent with anatomical evidence that Archaeolemur was well adapted for terrestrial locomotion as well as arboreal climbing.

A 61 cm core through a speleothem column in Drotsky's Cave, Botswana, has yielded a U-series dated pollen record of Holocene vegetation changes in the Kalahari Desert. Between c.10000-7000BP, the site was surrounded by an arid grassland with dry-adapted trees and shrubs such as Acacia and Commiphora. An increase in pollen of Combretaceae and Cyperaceae, and the appearance of pollen of such mesic savanna plants as Grewia between c. 7000—6000 BP, may indicate the onset of slightly wetter conditions. Combretaceae and other mesic pollen types increase between c. 6000-3000 BP, but the late Holocene record appears variable, with the period c. 5000-4000 BP being somewhat dryer than the millennia before and after. It would appear that Kalahari vegetation has changed less during the Holocene than many other African environments previously investigated. Despite the limitations imposed by pollen analysis of cave sites, the record from Drotsky's Cave shows good agreement with regional trends derived from other studies. The use of U-series dated pollen spectra derived from speleothems holds potential for expanding the geographic scope of palynological studies to areas lacking suitable lakes and bogs, and for extending the dated pollen record back an order of magnitude beyond the14C timescale.

SUMMARY Results from two years of pollen trapping experiments in New York State show that pollen spectra inside the three caves studied are highly similar to the pollen rain outside the caves. Statistical comparisons of modern pollen spectra derived from Tauber traps, speleothems, moss polsters, and nearby pond sediments suggest that pollen deposition inside caves can provide a reliable index of the regional and local vegetation, directly comparable to the more conventional spectra derived from lake sediments and moss polsters. Because of the relatively low pollen influx inside caves, however, stochastic and episodic forms of particle transport may influence pollen deposition inside caves in proportions that are unique to each site. With careful attention to site parameters such as entrance size, pollen preservation, and modes of sedimentation, investigators could make greater use of caves in palynological studies.

The origin of Madagascar’s highly endemic vertebrate fauna remains one of the great unsolved mysteries of natural history. From what landmasses did the basal stocks of this unique and imbalanced fauna come? When and how did the ancestral populations arrive on the island? How rapidly did they diversify, and why? The most direct means of addressing these questions, and other enigmas concerning the evolutionary and biogeographic history of Madagascar’s vertebrate fauna, is through discovery of fossils from a sequence of well-dated geological horizons. Many fossils relevant to these queries have been discovered by paleontologists in recent years ... but many more are being lost to commercial enterprises, both foreign and domestic, that have little or no regard for the scientific significance of fossils. The objectives of this essay are to 1) provide an overview of Madagascar’s vertebrate fossil record and its importance, 2) raise awareness concerning the illegal collection, exportation, and sale of vertebrate fossils, and 3) stress the importance of keeping vertebrate fossils from the island in the public domain. In light of these issues, we underscore the necessity for development of adequate repositories and support infrastructure in Madagascar to safeguard and display the country’s vertebrate fossil collections; doing so would ensure the preservation and appreciation of Madagascar’s rich natural heritage for future generations of scientists and Malagasy citizens alike.

Two significant events in the late Holocene history of Madagascar were (a) the arrival of people, and (b) the loss of nearly two dozen species of land vertebrates in the socalled “subfossil extinctions”. The consensus is that the faunal losses occurred shortly subsequent to human arrival, but the timing of these events is poorly constrained. The minimum age for initial human presence on the island may now be set at approximately 2000 bp, on the basis of AMS 14C dates for human-modified femora of extinct dwarf hippos from SW Madagascar. Assuming that this date also marks the beginning of deleterious human interactions with the subfossil fauna, and assuming that this fauna became completely extinct by 900 bp, the width of the anthropogenic “extinction window” may have been as long as c. 1000 a. This estimate, nearly twice the length of previous ones, is close to the unadjusted minimum for the duration of the terminal Pleistocene extinction event in the Americas. Whether or not this length of time comports with theoretical expectations of a “blitzkrieg” pattern of losses is uncertain, but greater refinement in dating the end of the subfossil extinctions is unlikely to produce radically shorter estimates of duration.

We report here definitive evidence of butchery, most probably associated with hunting, of giant extinct lemurs by early human settlers in Madagascar. Specimens of Palaeopropithecus ingens and Pachylemur insignis from two sites in southwestern Madagascar, Taolambiby and Tsirave, show classic signs of butchering. We compared these to the bones (also from Taolambiby) of butchered Propithecus verreauxi, a lemur still living in the region. The characteristics of the tool-induced extinct-lemur bone alterations (sharp cuts and chop marks near joints, oblique cuts along the shafts, spiral fractures, and percussion striae) suggest skinning, disarticulation, and filleting. Conclusive evidence of megafaunal modification by humans in Madagascar was limited previously to a few hippo and elephant bird bones and one extinct aye-aye tooth. New evidence comes not from archaeological sites, but from specimens collected in the early 1900s, without stratigraphic records, at ‘‘subfossil’’ sites (i.e., sites renowned for their late Pleistocene or Holocene fossils, often lacking human artifacts). Whereas these are hardly the most ideal samples for analysis of this kind, careful scrutiny of the characteristics of the cut marks has allowed us to document butchery beyond any reasonable doubt. One bone with definitive cut marks has been dated to the very earliest part of the human period in Madagascar. Continued, careful research on the bones in subfossil collections is warranted. 2005 Elsevier Ltd. All rights reserved.

A database has been assembled with 278 age determinations for Madagascar. Materials 14 C dated include pretreated sediments and plant macrofossils from cores and excavations throughout the island, and bones, teeth, or eggshells of most of the extinct megafaunal taxa, including the giant lemurs, hippopotami, and ratites. Additional measurements come from uranium-series dates on speleothems and thermoluminescence dating of pottery. Changes documented include late Pleistocene climatic events and, in the late Holocene, the apparently human-caused transformation of the environment. Multiple lines of evidence point to the earliest human presence at ca. 2300 14 C yr BP (350 cal yr BC). A decline in megafauna, inferred from a drastic decrease in spores of the coprophilous fungus Sporormiella spp. in sediments at 1720 ± 40 14 C yr BP (230–410 cal yr AD), is followed by large increases in charcoal particles in sediment cores, beginning in the SW part of the island, and spreading to other coasts and the interior over the next millennium. The record of human occupation is initially sparse, but shows large human populations throughout the island by the beginning of the Second Millennium AD. Dating of the “subfossil” megafauna, including pygmy hippos, elephant birds, giant tortoises, and large lemurs, demonstrates that most if not all the extinct taxa were still present on the island when humans arrived. Many taxa overlapped chronologically with humans for a millennium or more. The extinct lemurs Hadropithecus stenognathus , Pachylemur insignis , Mesopropithecus pithecoides , and Daubentonia robusta , and the elephant birds Aepyornis spp. and Mullerornis spp., were still present near the end of the First Millennium AD. Palaeopropithecus ingens , Megaladapis edwardsi , and Archaeolemur sp. (cf. edwardsi ) may have survived until the middle of the Second Millennium A.D. One specimen of Hippopotamus of unknown provenance dates to the period of European colonization.

Fossil spores of the dung fungus Sporormiella spp. in sediment cores from throughout Madagascar provide new information concerning megafaunal extinction and the introduction of livestock. Sporormiella percentages are very high in prehuman southwest Madagascar, but at the site with best stratigraphic resolution the spore declines sharply by ≈1,720 yr B.P. (radiocarbon years ago). Within a few centuries there is a concomitant rise in microscopic charcoal that probably represents human transformation of the local environment. Reduced megaherbivore biomass in wooded savannas may have resulted in increased plant biomass and more severe fires. Some now-extinct taxa persisted locally for a millennium or more after the inferred megafaunal decline. Sites in closed humid forests of northwest Madagascar and a montane ericoid formation of the central highlands show only low to moderate Sporormiella percentages before humans. A subsequent rise in spore concentrations, thought to be evidence for livestock proliferation, occurs earliest at Amparihibe in the northwest at ≈1,130 yr B.P.

Studying Madagascar’s late prehistoric past can add a useful dimension to ethnobotany research, as it has to conservation efforts. These studies provide evidence that people first arrived about two millennia ago. The plants they brought to Madagascar are predominantly south Asian in origin, including coconut, banana, rice, and hemp, pointing to their probable Indonesian origins. Later plant additions, such as castor bean, came from Africa and reflect a second wave of human migration. The subsequent development of indigenous agriculture was affected by the limitations of climate and soils, and also by the effects of ecological changes that were largely anthropogenic. Additional information on these remote times can be gleaned from early literature, especially Mediterranean and Islamic references. These types of multidisciplinary investigations, aimed at recovering additional early cultural and ecological elements, can have the positive effect of developing stronger ties between ecology and culture in Madagascar, perhaps helping to heal the unfortunate rift between conservation and the social sciences currently so evident there.