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Copyright of Lemur News is the property of Lemur News and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lemur News is the property of Lemur News and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phylogeographic barriers, together with habitat loss and fragmentation, contribute to the evolution of a species’ genetic diversity by limiting gene flow and increasing genetic differentiation among populations. Changes in connectivity can thus affect the genetic diversity of populations, which may influence the evolutionary potential of species and the survival of populations in the long term. We studied the genetic diversity of the little known Northern rufous mouse lemur (Microcebus tavaratra), endemic to Northern Madagascar. We focused on the population of M. tavaratra in the Loky-Manambato region, Northern Madagascar, a region delimited by two permanent rivers and characterized by a mosaic of fragmented forests. We genotyped 148 individuals at three mitochondrial loci (D-loop, cytb, and cox2) in all the major forests of the study region. Our analyses suggest that M. tavaratra holds average genetic diversity when compared to other mouse lemur species, and we identified two to four genetic clusters in the study region, a pattern similar to that observed in another lemur endemic to the region (Propithecus tattersalli). The main cluster involved samples from the two mountain forests in the study region, which were connected until recently. However, the river crossing the study region does not appear to be a strict barrier to gene flow in M. tavaratra. Finally, the inferred demographic history of M. tavaratra suggests no detectable departure from stationarity over the last millennia. Comparisons with codistributed species (P. tattersalli and two endemic rodents, Eliurus spp.) suggest both differences and similarities in the genetic clusters identified (i.e., barriers to species dispersal) and in the inferred demographic history. These comparisons suggest that studies of codistributed species are important to understand the effects of landscape features on species and to reconstruct the history of habitat changes in a region. [ABSTRACT FROM AUTHOR]

Despite the fact that lemurs are the most threatened group of mammals and live in one of the world's richest biodiversity hotspots, there are still lemur lineages and regions of Madagascar that suffer from a lack of naturalistic data. This is particularly striking for the genus Phaner as well as for many unprotected forests of Northeastern Madagascar. We detected the presence of Phaner in the isolated lowland dry forest of Analafiana, located south of the Manambato River and close to the city of Vohémar. Little is known about the presence of Phaner in this region. The only record of Phaner in the area around Analafiana comes from museum specimens (Groves and Tattersall, 1991) geographically assigned to Vohémar and identified as belonging to a "doubtful subspecies". Here we provide morphological and genetic (mitochondrial DNA) data for a single juvenile individual captured in Analafiana. We compare our sequence data to the only four Phaner sequences publicly available: two P. electromontis individuals sampled in Montagne d'Ambre and Ankarana, and two other from P. pallescens and P. parienti species. We find that the new mtDNA sequence is divergent from the two P. electromontis sequences, but closer to these than other Phaner sequences. We also note that the Analafiana Phaner individual is morphologically more similar to P. electromontis than to the other species. Altogether, this data suggests this unique and isolated population of Phaner survives in the unprotected Analafiana forest in northeastern Madagascar. It is urgent to carry out more genetic, behavioral, acoustic, and demographic research in this region and on this population, whose exact taxonomic status should be urgently clarified. Our results strongly suggest that Analafiana's Phaner population likely holds the memory of a unique evolutionary history. [ABSTRACT FROM AUTHOR]

Propithecus coronatus is an endangered, diurnal forest-dwelling lemur of northwestern Madagascar. We conducted the first extensive population genetic study for this species. We designed new primers to amplify and sequence the mitochondrial D-loop of 125 individuals from 14 localities in the northern part of the species' distribution. Our aim was to assess the genetic variability and differentiation of this species in a fragmented landscape. Compared to other lemurs, crowned sifakas have a moderate level of haplotype diversity (0.853) and a low nucleotide diversity (1.21%). Despite the considerable forest fragmentation in the region surveyed, the species does not show strong signals of genetic structure as shown by the ΦST estimates, the network of haplotypes, and the limited correlation between genetic and geographic distance. The current mtDNA estimated effective population size was relatively large (median: 11,262; 95% HPD: 5,107-20,083), in agreement with recent census estimates, suggesting that a large number of individuals is still present across the species range. Using the Extended Bayesian Skyline Plot (EBSP) approach to reconstruct the demographic history of the species, we did not detect any genetic signal of change in population size. Despite the ongoing loss and fragmentation of their habitat, the population still harbors subtantial genetic diversity, likely as a partial consequence of a taboo against hunting the crowned sifaka among the Sakalava ethnic group inhabiting the area. [ABSTRACT FROM AUTHOR]

Copyright of Madagascar Conservation & Development is the property of Journal Madagascar Wildlife Conservation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lemur News is the property of Lemur News and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lemur News is the property of Lemur News and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Global biodiversity is under accelerating threats, and species are succumbing to extinction before being described. Madagascar's biota represents an extreme example of this scenario, with the added complication that much of its endemic biodiversity is cryptic. Here we illustrate best practices for clarifying cryptic diversification processes by presenting an integrative framework that leverages multiple lines of evidence and taxon-informed cut-offs for species delimitation, while placing special emphasis on identifying patterns of isolation by distance. We systematically apply this framework to an entire taxonomically controversial primate clade, the mouse lemurs (genus Microcebus, family Cheirogaleidae). We demonstrate that species diversity has been overestimated primarily due to the interpretation of geographic variation as speciation, potentially biasing inference of the underlying processes of evolutionary diversification. Following a revised classification, we find that crypsis within the genus is best explained by a model of morphological stasis imposed by stabilizing selection and a neutral process of niche diversification. Finally, by clarifying species limits and defining evolutionarily significant units, we provide new conservation priorities, bridging fundamental and applied objectives in a generalizable framework., (© 2024. The Author(s).)

Objectives: The investigation of morphological variation in animals is widely used in taxonomy, ecology, and evolution. Using large datasets for meta-analyses has dramatically increased, raising concerns about dataset compatibilities and biases introduced by contributions of multiple researchers., Materials and Methods: We compiled morphological data on 13 variables for 3073 individual mouse lemurs (Cheirogaleidae, Microcebus spp.) from 25 taxa and 153 different sampling locations, measured by 48 different researchers. We introduced and applied a filtering pipeline and quantified improvements in data quality (Shapiro-Francia statistic, skewness, and excess kurtosis). The filtered dataset was then used to test for genus-wide sexual size dimorphism and the applicability of Rensch's, Allen's, and Bergmann's rules., Results: Our pipeline reduced inter-observer bias (i.e., increased normality of data distributions). Inter-observer reliability of measurements was notably variable, highlighting the need to reduce data collection biases. Although subtle, we found a consistent pattern of sexual size dimorphism across Microcebus, with females being the larger (but not heavier) sex. Sexual size dimorphism was isometric, providing no support for Rensch's rule. Variations in tail length but not in ear size were consistent with the predictions of Allen's rule. Body mass and length followed a pattern contrary to predictions of Bergmann's rule., Discussion: We highlighted the usefulness of large multi-researcher datasets for testing ecological hypotheses after correcting for inter-observer biases. Using genus-wide tests, we outlined generalizable patterns of morphological variability across all mouse lemurs. This new methodological toolkit aims to facilitate future large-scale morphological comparisons for a wide range of taxa and applications., (© 2023 Wiley Periodicals LLC.)