Madagascar’s mouse lemurs ( Microcebus ) comprise a diverse clade of cryptic species, which were historically discriminated using genetic data, distribution, as well as diagnostic mating calls. However, the mating calls are well described only for a small number of mouse lemur species. Focussing on two closely related Microcebus taxa, we hypothesised that environment-driven change in communication signal, or sensory drive, contributed to this diversity. In order to test this hypothesis, we characterised the courtship of Microcebus griseorufus . We used ultrasonic recordings and sound transmission trials to compare the attenuation of male mating trills of M. griseorufus and sympatric M. murinus in their respective preferred habitats. Differences in habitat had an influence on the reverberation, also affecting the call, with M. griseorufus mating call presenting more modulations than the simpler call of M. murinus . Our results confirm that mating calls are selected in response to environmental conditions and local habitat, as formulated by the sensory drive hypothesis. Trill attenuation also explains mating call differences (complex or simple) leading to interspecific variation predicted in the recognition concept of species.

Based on the Recognition Concept of species, the specific-mate contact model posits that mating systems develop as combinations of two fundamental courtship strategies that we interpret here in terms of behavioural heterochrony: territorial mate-attraction evolved as an effect of peramorphosis whereas group-living mate-seeking evolved as an effect of paedomorphosis. We tested this hypothesis on primates in a phylogenetic and paleo-climatic context. Our results suggest that primate promiscuity (both males and females are mate-seekers) evolved with group-living from ancestral pair-living monogamy (both males and females are mate-attractors) in the Palaeogene, as the result of a slowdown in growth (neoteny) caused by increased environmental predictability. A secondary return to territorial monogamy probably evolved as the result of accelerated growth driven by seasonality (acceleration). Polygamy evolved in the Neogene during periods of forest fragmentation and environmental unpredictability. Small monogamous ancestors evolved seasonal polyandry (female attraction) as an effect of truncated development (progenesis). Large promiscuous, neotenic ancestors evolved non-seasonal polygyny (male attraction) as an effect of prolonged development (hypermorphosis) in males. We conclude that social heterochrony offers alternative explanations for the coevolution of life history and mating be-haviour; and we discuss the implications of our model for human social evolution.

Madagascar's vertebrate fauna is the result of an intricate biogeographic history not considered in the models developed to explain colonization on other islands. For 80 years popular opinion has held that most of Madagascar's terrestrial vertebrate fauna arrived via transoceanic dispersal (i.e., by rafting or swimming), chiefly from Africa. The alternative solution of recurrent uplifts of a land bridge connected with cyclic global kinematic revolutions, proposed in 2021, was recently challenged. The 2021 paper demonstrates the strength of a comprehensive holistic approach (sedimentary, tectonic, kinematic, and palaeo-environmental studies) based on the new, large-scale dataset provided by the PAMELA (Passive Margins Exploration Laboratories) research project. This episodic land bridges hypothesis was tested with divergence estimates of dispersal mechanisms of Madagascar's Angiosperm taxa. The present study includes preliminary palynological results obtained on the latest Miocene to earliest Pliocene material from DSDP Site 242. These pollen assemblages are illustrative of vegetation belts from the coastline to high relief, i.e., from mangrove up to montane forests including intermediate low altitude vegetation.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Geodispersal as a Biogeographic Mechanism for Cenozoic Exchanges between Madagascar and Africa Judith C Masters, Fabien Génin, Romain Pellen, Paul P A Mazza, Yurui Zhang, Thierry Huck, Marina Rabineau, Daniel Aslanian

Interspecific associations may limit the dispersal of individual species, but may also facilitate it when entire co-evolved systems expand their geographic ranges. We tested the recent proposal that episodic land bridges linked Africa and Madagascar at three stages during the Cenozoic by comparing divergence estimates of Madagascar's angiosperm taxa with their dispersal mechanisms. Plants that rely on gravity for seed dispersal indicate at least two episodes of land connection between Africa and Madagascar, in the Early Palaeocene and Early Oligocene. Seed dispersal by strepsirrhine primates possibly evolved in the Palaeocene, with the divergence of at least one endemic Malagasy angiosperm genus, Burasaia (Menispermaceae). This genus may have facilitated the lemur colonization of Madagascar. Frugivory, nectarivory and gummivory probably generalized in the Oligocene, with the co-evolution of modern lemurs and at least 10 new Malagasy angiosperm families. In the Late Miocene, more angiosperms were probably brought from Africa by birds via a discontinuous land connection, and radiated on Madagascar in diffuse association with birds (asities) and dwarf nocturnal lemurs (cheirogaleids). During the same connective episode, Madagascar was probably colonized by hippopotamuses, which both followed and re-seeded a variety of plants, forming the grassy Uapaca 'tapia' forest and ericoid 'savoka' thicket.

The vestibular system of the mammalian inner ear senses angular and linear velocity of the head and enables animals to maintain their balance. Vestibular anatomy has been studied extensively in order to link its structure to particular kinds of locomotion. Available evidence indicates that, in primates, slow-moving species show higher levels of vestibular variation than fast-moving taxa. We analysed intraspecific morphological variation and fluctuating asymmetry (FA) levels in the semicircular canal systems of six species of lorisiform primates: three slow-moving lorisids and three fast-moving galagids. Our results showed clear differences in levels of intraspecific variation between slow-moving and fast-moving taxa. Higher levels of variation were responsible for deviations from coplanarity for synergistic pairs of canals in slower taxa. Lorisids also presented higher levels of FA than galagids. FA is a better indicator of agility than intraspecific variation. These results suggest that in order to function efficiently in fast taxa, semicircular canal systems must develop as symmetrically as possible, and should minimise the deviation from coplanarity for synergistic pairs. Higher levels of variation and asymmetry in slow-moving taxa may be related to lower levels of stabilising selection on the vestibular system, linked to a lower demand for rapid postural changes.

The vestibular system of the inner ear, highly involved in maintaining balance during activities and positional behaviour of animals, has been deeply studied in order to link its morphology with the specific type of locomotion. Previous studies (e.g. Perier et al. 2016, Gonzales et al. 2018) have shown that, in primates, the amount of morphological variation is higher in slow-moving species than in fast-moving ones. These results indicate a lower selective pressure and a reduced functional demand for postural adjustments in the former group, and a higher selective pressure for balance and postural capabilities in the latter. In this study, we assessed if the difference in selective pressure are also linked to the fuctuating asymmetry levels of the vestibular system, and to which extent. Fluctuating asymmetry is defined as a non-directional variation between left and right sides of a bilateral character, and it may rise as a result of an inability to control development under genetic or environmental stress. There are very few analyses of the interspecific variation of the asymmetry levels of this organ in mammals in general (Berlin et al. 2013), and to our knowledge none so far at the intraspecific level. Here we analyzed the intraspecific variation of the bony labyrinth (inner ear) morphology and of the fuctuating asymmetry levels of left and right labyrinths among six species of lorisiform primates differing in their activities and positional behaviours of their locomotor repertoires: three being slow-moving (Loris tardigradus, Nycticebus coucang, and Perodicticus potto), and three being fast-moving taxa (Paragalago granti, Galago moholi, and Otolemur crassicaudatus). Our results highlight the difference in amount of intraspecific variation between slow-moving and fast-moving taxa. Furthermore, fuctuating asymmetry levels of slow-moving taxa also tend to be higher than in fast-moving taxa. Based on these results, it may be expected that relaxation of the selective pressure applied to the morphology of the bony labyrinth is the likely reason for this higher amount of intraspecific variation and asymmetry levels in slow-moving taxa, and that it may be related to a decreased demand for rapid postural changes.

Despite increasing awareness of issues affecting inclusivity, equity and diversity, change has been slow in science and academia, and gender disparities remain significant. Biogeography has not escaped this pattern. Here, we present a virtual issue compiling some of the most cited papers led by women that have been published in the Journal of Biogeography since 2009 in an effort to equalize visibility of women's influential work. We summarize leading gender disparities and their potential underlying causes, and present our motivation and methodology in compiling this issue. We further provide a blog, website and social media links to highlight the research of the authors whose work is showcased here. Highlighting influential contributions by women biogeographers is a small step towards equalizing visibility across genders. We hope that this virtual issue will also contribute in some way to creating a greater sense of belonging for women biogeographers.

For 80 years, popular opinion has held that most of Madagascar's terrestrial vertebrates arrived from Africa by transoceanic dispersal (i.e. rafting or swimming). We reviewed this proposition, focussing on three ad hoc hypotheses proposed to render this unlikely scenario more feasible: (a) Could hibernation have helped mammals to reach Madagascar? (b) Could the aquatic abilities of hippopotamuses have enabled them to swim the Mozambique Channel? (c) How valid is the Ali‐Huber model predicting that eastward Palaeogene surface currents allowed rafts to reach Madagascar in 3–4 weeks? Finally, we explored the alternative hypothesis of geodispersal via short‐lived land bridges between Africa and Madagascar.

OBJECTIVES:Phylogenies consistently group the folivorous Lepilemur species with the small-bodied insectivorous-frugivorous cheirogaleids. Juvenile lepilemurs and adult cheirogaleids share allometries in most aspects of skull morphology, except the palate. We investigated potential influences on palate shape in these taxa and several outgroups using geometric morphometrics.MATERIALS AND METHODS:Our sample included representatives of four extant strepsirrhine families, Cheirogaleidae (including Lepilemurinae), Lemuridae, Indriidae, and Galagidae, and one subfossil Megaladapis. Our dataset comprised 32 landmarks collected from 397 specimens representing 15 genera and 28 species, and was analyzed using generalized procrustes analyses and between group principal component analysis. We explored the influence of size, phylogeny, diet, and the propagation of loud vocalizations on palate shape.RESULTS:While congeneric species clustered within the morphospace, the phylomorphospace did not mirror molecular phylogenetic hypotheses of higher-order relationships. Four palate forms were distinguished within the Cheirogaleidae. Diet, strongly linked to body size, had the single greatest influence on palate shape. The production of long-distance advertisement calls was most often associated with positive scores on the PC1 axis.DISCUSSION:Our results suggest that the extensive variation in palate shape among Cheirogaleidae is related to dietary shifts that accompanied changes in body size during the clade's radiation. Molecular phylogenies indicate that cheirogaleid diversification involved repeated dwarfing events, which in turn drove dietary shifts from ancestral folivory-frugivory to frugivory, gummivory, and faunivory in the descendant species. The elongated Lepilemur palate is probably related to accelerated eruption of the cheek teeth to render juveniles competent to shear leaves upon weaning.

Objectives Phylogenies consistently group the folivorousLepilemurspecies with the small-bodied insectivorous-frugivorous cheirogaleids. Juvenile lepilemurs and adult cheirogaleids share allometries in most aspects of skull morphology, except the palate. We investigated potential influences on palate shape in these taxa and several outgroups using geometric morphometrics. Materials and Methods Our sample included representatives of four extant strepsirrhine families, Cheirogaleidae (including Lepilemurinae), Lemuridae, Indriidae, and Galagidae, and one subfossilMegaladapis. Our dataset comprised 32 landmarks collected from 397 specimens representing 15 genera and 28 species, and was analyzed using generalized procrustes analyses and between group principal component analysis. We explored the influence of size, phylogeny, diet, and the propagation of loud vocalizations on palate shape. Results While congeneric species clustered within the morphospace, the phylomorphospace did not mirror molecular phylogenetic hypotheses of higher-order relationships. Four palate forms were distinguished within the Cheirogaleidae. Diet, strongly linked to body size, had the single greatest influence on palate shape. The production of long-distance advertisement calls was most often associated with positive scores on the PC1 axis. Discussion Our results suggest that the extensive variation in palate shape among Cheirogaleidae is related to dietary shifts that accompanied changes in body size during the clade's radiation. Molecular phylogenies indicate that cheirogaleid diversification involved repeated dwarfing events, which in turn drove dietary shifts from ancestral folivory-frugivory to frugivory, gummivory, and faunivory in the descendant species. The elongatedLepilemurpalate is probably related to accelerated eruption of the cheek teeth to render juveniles competent to shear leaves upon weaning.

The purpose of this application, under Articles 11, 23, 31 and 32 of the Code, is to confirm the availability of and to maintain the usage of the name Galago demidoffFischer, 1806 for Demidoff's Dwarf Galago from western and central Africa and its priority over the objective junior synonym Macropus (Galago) demidoviiFischer, 1808, and to suppress subsequent incorrect spellings, under Articles 19 and 33 of the Code. The original specimen of Galago demidoffFischer, 1806 has been destroyed so a further purpose of this application is to designate a neotype, under Article 75.3 of the Code. A name of dubious identity, Lemur minutusCuvier, 1797, has been confused with that of Galago demidoff and Galago senegalensisGeoffroy, 1796. This name has had no valid usage for well over a century and is here regarded as a nomen oblitum, under Article 23 of the Code. In order to clarify taxonomic status, it is also proposed to designate a neotype for Lemur minutusCuvier, 1797, under Article 75.3 of the Code. It is proposed that G. demidoff should be maintained as the prior name for the taxon and that all subsequent incorrect spellings of the name be suppressed.

This article examines the potential for UK local authorities to work together to make best use of the resources available for road management, at a time when budgeted finances are not increasing fast enough to meet needs. Local authority resources are more likely to be aimed at education and social services. This leads to crisis management in highways administration. A recent conference looked at the contribution that well-managed roads make towards social cohesion and local economic viability, and noted that better highways maintenance reduced injury claims on local authorities. Councils need to look at other ways to access finances or reduce costs: shared services is one option. This includes services provided to, or delivered jointly with, another authority; and joint procurement for economy of scale. All the councils involved need to ensure they get maximum public value. Activities from different departments can be co-ordinated, while effective asset management can contribute to wider goals. Sharing services requires trust, co-operation and making the most of opportunities. Brief case studies are presented: from Dorset, south-west England; and Tayside, Scotland.