The terrestrial and marine biotypes of Madagascar are critical priorities for conservation, with almost unparalleled levels of endemism, species diversity and human threat for a land area of its size. Field inventories and molecular-based research conducted from the mid 1980s to present have greatly expanded knowledge of the country's biota, for some groups with nearly exponential growth in measures of species diversity. I provide updated measures of estimated species diversity between a book with 289 contributors, published in 2003 (The Natural History of Madagascar), and a full-scale update with 539 contributors, published in 2022 (The New Natural History of Madagascar). I compare biodiversity information presented in the new book with data from the earlier book, providing insight into scientific advancements, and revised estimates of species richness and endemism of a range of taxonomic groups.

Despite their legal protection status, protected areas (PAs) can benefit from priority ranks when ongoing threats to their biodiversity and habitats outpace the financial resources available for their conservation. It is essential to develop methods to prioritize PAs that are not computationally demanding in order to suit stakeholders in developing countries where technical and financial resources are limited. We used expert knowledge-derived biodiversity measures to generate individual and aggregate priority ranks of 98 mostly terrestrial PAs on Madagascar. The five variables used were state of knowledge (SoK), forest loss, forest loss acceleration, PA size and relative species diversity, estimated by using standardized residuals from negative binomial models of SoK regressed onto species diversity. We compared our aggregate ranks generated using unweighted averages and principal component analysis (PCA) applied to each individual variable with those generated via Markov chain (MC) and PageRank algorithms. SoK significantly affected the measure of species diversity and highlighted areas where more research effort was needed. The unweighted- and PCA-derived ranks were strongly correlated, as were the MC and PageRank ranks. However, the former two were weakly correlated with the latter two. We recommend using these methods simultaneously in order to provide decision-makers with the flexibility to prioritize those PAs in need of additional research and conservation efforts.

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.

The mammal family Tenrecidae (Afrotheria: Afrosoricida) is endemic to Madagascar. Here we present the conservation priorities for the 31 species of tenrec that were assessed or reassessed in 2015–2016 for the IUCN Red List of Threatened Species. Six species (19.4%) were found to be threatened (4 Vulnerable, 2 Endangered) and one species was categorized as Data Deficient. The primary threat to tenrecs is habitat loss, mostly as a result of slash-and-burn agriculture, but some species are also threatened by hunting and incidental capture in fishing traps. In the longer term, climate change is expected to alter tenrec habitats and ranges. However, the lack of data for most tenrecs on population size, ecology and distribution, together with frequent changes in taxonomy (with many cryptic species being discovered based on genetic analyses) and the poorly understood impact of bushmeat hunting on spiny species (Tenrecinae), hinders conservation planning. Priority conservation actions are presented for Madagascar's tenrecs for the first time since 1990 and focus on conserving forest habitat (especially through improved management of protected areas) and filling essential knowledge gaps. Tenrec research, monitoring and conservation should be integrated into broader sustainable development objectives and programmes targeting higher profile species, such as lemurs, if we are to see an improvement in the conservation status of tenrecs in the near future.

Probit analysis identified factors that influence the adoption of precision farming technologies by Southeastern cotton farmers. Younger, more educated farmers who operated larger farms and were optimistic about the future of precision farming were most likely to adopt site-specific information technology. The probability of adopting variable-rate input application technology was higher for younger farmers who operated larger farms, owned more of the land they farmed, were more informed about the costs and benefits of precision farming, and were optimistic about the future of precision farming. Computer use was not important, possibly because custom hiring shifts the burden of computer use to agribusiness firms.

Based on niche theory, closely related and morphologically similar species are not predicted to coexist due to overlap in resource and habitat use. Local assemblages of bats often contain cryptic taxa, which co-occur despite notable similarities in morphology and ecology. We measured in two different habitat types on Madagascar levels of stable carbon and nitrogen isotopes in hair (n = 103) and faeces (n = 57) of cryptic Vespertilionidae taxa to indirectly examine whether fine-grained trophic niche differentiation explains their coexistence. In the dry deciduous forest (Kirindy), six sympatric species ranged over 6.0‰ in δ15N, i.e. two trophic levels, and 4.2‰ in δ13C with a community mean of 11.3‰ in δ15N and −21.0‰ in δ13C. In the mesic forest (Antsahabe), three sympatric species ranged over one trophic level (δ15N: 2.4‰, δ13C: 1.0‰) with a community mean of 8.0‰ δ15N and −21.7‰ in δ13C. Multivariate analyses and residual permutation of Euclidian distances in δ13C–δ15N bi-plots revealed in both communities distinct stable isotope signatures and species separation for the hair samples among coexisting Vespertilionidae. Intraspecific variation in faecal and hair stable isotopes did not indicate that seasonal migration might relax competition and thereby facilitate the local co-occurrence of sympatric taxa.

Bats are important components in tropical mammal assemblages. Unravelling the mechanisms allowing multiple syntopic bat species to coexist can provide insights into community ecology. However, dietary information on component species of these assemblages is often difficult to obtain. Here we measured stable carbon and nitrogen isotopes in hair samples clipped from the backs of 94 specimens to indirectly examine whether trophic niche differentiation and microhabitat segregation explain the coexistence of 16 bat species at Ankarana, northern Madagascar. The assemblage ranged over 4.4‰ in δ15N and was structured into two trophic levels with phytophagous Pteropodidae as primary consumers (c. 3‰ enriched over plants) and different insectivorous bats as secondary consumers (c. 4‰ enriched over primary consumers). Bat species utilizing different microhabitats formed distinct isotopic clusters (metric analyses of δ13C–δ15N bi-plots), but taxa foraging in the same microhabitat did not show more pronounced trophic differentiation than those occupying different microhabitats. As revealed by multivariate analyses, no discernible feeding competition was found in the local assemblage amongst congeneric species as compared with non-congeners. In contrast to ecological niche theory, but in accordance with studies on New and Old World bat assemblages, competitive interactions appear to be relaxed at Ankarana and not a prevailing structuring force.

The Madagascar Red Owl, known from the eastern rainforest of central Madagascar by a few specimens collected in the nineteenth and early twentieth century and one sight record in 1973, was rediscovered in late July 1993 in north-eastern Madagascar. An adult bird, held in captivity for approximately one year, was located in the town of Andapa. According to the owner, the owl had been obtained south-west of Andapa, near the village of Antanamangotroka, in a forested area connected to the Réserve Spéciale d'Anjanaharibe-Sud, and at about 800 m above sea-level. This record expands the known geographic range of this species and provides the first documentation of its continued existence in over 20 years.

La Chouette de Soumagne, connue de la forêt pluviale orientale du Domaine du Centre de Madagascar à travers quelques spécimens collectés au 19ème siècle et début du 20ème siècle et d'aprés une observation en 1973, a été redécouverte à la fin du mois de juillet 1993 au nord-est de Madagascar. Un individu adulte, qui venait de passer plus d'un an en captivité, a été découvert dans la ville d'Andapa. D'après la personne qui détenait l'animal, la chouette avait été capturee au sud-ouest d'Andapa, pres du village d'Antanamangotroka, au sein d'une zone forestière connectée avec la Réserve Spéciale d'Anjanaharibe-Sud, à une altitude d'environ 800 m au-dessus du niveau de la mer. Cette nouvelle donnée constitue une expansion significative de l'aire de distribution de cette espèce et apporte la preuve de la survie de cette espèce endémique qui n'avait pas été observee depuis plus de 20 ans.

The Red-tailed Newtonia Newtonia fanovanae, previously known from a single specimen from the eastern rainforest of central Madagascar, was rediscovered in October 1989 in the Marosohy Forest in the south-east of the island. In the study area, N. fanovanae occurs in the middle and upper section of the canopy of humid forest between 300 and 1,300 m. Ecological relationships with the other two sympatric Newtonia, amphichroa and brunneicauda, are discussed. The main morphological differences between fanovanae and the other two sympatric species are that the former has relatively long wings and short tarsi. The song of fanovanae is described and compared to other members of the genus. Our observations on the morphology, behaviour and vocalisations of N. fanovanae confirm its validity as a species.

Le Newtonie à queue rouge Newtonia fanovanae jusqu'à presént uniquement connu d'un seul spécimen provenant de la partie orientale de la forêt tropicale du Madagascar central, fût redécouvert en octobre 1989 dans la forêt de Marosohy au sud-est de l'île. N. fanovanae fût rencontré dans les parties moyennes et supérieures du feuillage de la forêt humide entre 300 et 1,300 m d'altitude. Les relations écologiques avec les deux espèces sympatriques de Newtonia, amphichroa et brunneicauda sont discutées. Les différences morphologiques principales entre fanovanae et les deux espéces sympatriques sont que celle-ci a des ailes relativement longues et des tarses courts. Le chant de fanovanae est decrit et comparé avec celui d'autres membres du genre. Nos observations sur la morphologie, le comportement et les vocalizations de N. fanovanae confirment sa validité comme bonne espéce.

In February 2005 clear evidence was found of extensive hunting by local people of microchiropteran bats in south-western Madagascar. Hipposideros commersoni (Family Hipposideridae) accumulates heavy fat deposits during this period, weighing on average about 50 g, and is the targeted species. The capture of other smaller species of microchiropterans appears to be incidental. The exploitation of bats for bushmeat in this region takes place during a period of food shortage, and because the level of collection surpasses the breeding potential of these animals it may over time result in extirpation of local populations.

We carried out extensive field surveys in the dry forest portions of Madagascar to document the species of bats occurring in these regions. These data combined with information in the literature and museum specimen records indicate that 28 species of Chiroptera occur in this region of the island, of which we documented 27 during our inventories. The community composition at sites occurring in areas of water-eroded sedimentary rock is notably different from sites on alluvial substrates. In contrast to the majority of native land mammal species on Madagascar, much of the microchiropteran fauna is not dependent on large tracts of intact forest and anthropogenic perturbations of forests may have less direct impact on their long-term survival. Conservation strategies for Chiroptera in the dry regions of the island should focus on reducing various types of human disturbance of cave environments.

Madagascar is a critical priority for international conservation efforts, based on almost unparalleled levels of endemism, species diversity, and human threat. Field research conducted over the past two decades has greatly expanded knowledge of the island's biota, making it difficult for any single research team to maintain up to date estimates of biodiversity and endemism across taxonomic groups. The recent publication of The Natural History of Madagascar, a synthesis by nearly 300 contributors from a wide range of disciplines, provides the means to update these estimates. Here, we summarize biodiversity information presented in the volume by providing revised estimates of species richness, endemism, and state of knowledge of a wide variety of taxonomic groups occurring on the island.

In the order Lipotyphla (Insectivora), certain reproductive features differ quite distinctly from the eutherian norms, and are of interest with regard to the evolution of mammalian gamete function and perhaps for questions of lipotyphlan phylogeny. As seen in one or more members of five lipotyphlan families (shrews, moles, hedgehogs, golden moles, tenrecs), these features can involve the configuration of the male tract including the penis, the morphology of the sperm head, the anatomy of the oviduct and the patterns of sperm transport within it, the character of the cumulus oophorus, and the way in which fertilising spermatozoa interact with the eggs. However, the picture is by no means uniform within the order. Reproductive idiosyncrasies occur variously in the different lipotyphlan families, and appear consistently and strikingly in shrews – the group studied most extensively. Compared to the patterns in most Eutheria, the most interesting anomalies in soricids include (a) the regulation of sperm transport to the site of fertilisation by oviduct crypts, whose arrangement can vary even according to species, (b) a circumscribed matrix-free cumulus oophorus that appears essential for fertilisation as the inducer of the acrosome reaction, (c) barbs on the acrosome-reacted sperm head by which it may attach to the zona pellucida.

With regard to the bearing such reproductive traits might have on lipotyphlan systematics, the African mouse shrew (Myosorex varius) displays a mix of traits that characterize either crocidurine or soricine shrews, consistent with the proposal that it belongs in a more primitive tribe, Myosoricinae, or subfamily, the Crocidosoricinae, from which the crocidurine and soricine lines probably evolved. Moreover, although elephant shrews are assigned now to a separate order (Macroscelidea), they display several of the unusual reproductive features seen in lipotyphlans, particularly in chrysochlorids and tenrecs. On the other hand, if used as a phylogenetic yardstick, none of the reproductive features described serves to define the Lipotyphla as classically constituted within one order, nor necessarily all the relationships suggested by recent sequencing studies of nuclear and mitochondrial genes.