Biogeography and taxonomy of extinct and endangered monk seals illuminated by ancient DNA and skull morphology

Extinctions and declines of large marine vertebrates have major ecological impacts and are of critical concern in marine environments. The Caribbean monk seal, Monachus tropicalis, last definitively reported in 1952, was one of the few marine mammal species to become extinct in historical times. Despite its importance for understanding the evolutionary biogeography of southern phocids, the relationships of M. tropicalis to the two living species of critically endangered monk seals have not been resolved. In this study we present the first molecular data for M. tropicalis, derived from museum skins. Phylogenetic analysis of cytochrome b sequences indicates that M. tropicalis was more closely related to the Hawaiian rather than the Mediterranean monk seal. Divergence time estimation implicates the formation of the Panamanian Isthmus in the speciation of Caribbean and Hawaiian monk seals. Molecular, morphological and temporal divergence between the Mediterranean and "New World monk seals" (Hawaiian and Caribbean) is profound, equivalent to or greater than between sister genera of phocids. As a result, we classify the Caribbean and Hawaiian monk seals together in a newly erected genus, Neomonachus. The two genera of extant monk seals (Monachus and Neomonachus) represent old evolutionary lineages each represented by a single critically endangered species, both warranting continuing and concerted conservation attention and investment if they are to avoid the fate of their Caribbean relative.Dirk-Martin Scheel, Graham J. Slater, Sergios-Orestis Kolokotronis, Charles W. Potter, David S. Rotstein, Kyriakos Tsangaras, Alex D. Greenwood, Kristofer M. Helge

Taxonomic revision of the olingos (Bassaricyon), with description of a new species, the Olinguito

Published 15 August 2013We present the first comprehensive taxonomic revision and review the biology of the olingos, the endemic Neotropical procyonid genus Bassaricyon, based on most specimens available in museums, and with data derived from anatomy, morphometrics, mitochondrial and nuclear DNA, field observations, and geographic range modeling. Species of Bassaricyon are primarily forest-living, arboreal, nocturnal, frugivorous, and solitary, and have one young at a time. We demonstrate that four olingo species can be recognized, including a Central American species (Bassaricyon gabbii), lowland species with eastern, cis-Andean (Bassaricyon alleni) and western, trans-Andean (Bassaricyon medius) distributions, and a species endemic to cloud forests in the Andes. The oldest evolutionary divergence in the genus is between this last species, endemic to the Andes of Colombia and Ecuador, and all other species, which occur in lower elevation habitats. Surprisingly, this Andean endemic species, which we call the Olinguito, has never been previously described; it represents a new species in the order Carnivora and is the smallest living member of the family Procyonidae. We report on the biology of this new species based on information from museum specimens, niche modeling, and fieldwork in western Ecuador, and describe four Olinguito subspecies based on morphological distinctions across different regions of the Northern Andes.Kristofer M. Helgen, C. Miguel Pinto, Roland Kays, Lauren E. Helgen, Mirian T. N. Tsuchiya, Aleta Quinn, Don E. Wilson, Jesús E. Maldonad

Genomic analysis reveals hidden biodiversity within colugos, the sister group to primates

Colugos are among the most poorly studied mammals despite their centrality to resolving supraordinal primate relationships. Two described species of these gliding mammals are the sole living members of the order Dermoptera, distributed throughout Southeast Asia. We generated a draft genome sequence for a Sunda colugo and a Philippine colugo reference alignment, and used these to identify colugo-specific genetic changes that were enriched in sensory and musculoskeletal-related genes that likely underlie their nocturnal and gliding adaptations. Phylogenomic analysis and catalogs of rare genomic changes overwhelmingly support the contested hypothesis that colugos are the sister group to primates (Primatomorpha), to the exclusion of treeshrews. We captured ~140 kb of orthologous sequence data from colugo museum specimens sampled across their range and identified large genetic differences between many geographically isolated populations that may result in a >300% increase in the number of recognized colugo species. Our results identify conservation units to mitigate future losses of this enigmatic mammalian order.Victor C. Mason, Gang Li Patrick Minx, Jürgen Schmitz, Gennady Churakov, Liliya Doronina, Amanda D. Melin ... et al

Strategies for assessing the implications of malformed frogs for environmental health.

The recent increase in the incidence of deformities among natural frog populations has raised concern about the state of the environment and the possible impact of unidentified causative agents on the health of wildlife and human populations. An open workshop on Strategies for Assessing the Implications of Malformed Frogs for Environmental Health was convened on 4-5 December 1997 at the National Institute of Environmental Health Sciences in Research Triangle Park, North Carolina. The purpose of the workshop was to share information among a multidisciplinary group with scientific interest and responsibility for human and environmental health at the federal and state level. Discussions highlighted possible causes and recent findings directly related to frog deformities and provided insight into problems and strategies applicable to continuing investigation in several areas. Possible causes of the deformities were evaluated in terms of diagnostics performed on field amphibians, biologic mechanisms that can lead to the types of malformations observed, and parallel laboratory and field studies. Hydrogeochemistry must be more integrated into environmental toxicology because of the pivotal role of the aquatic environment and the importance of fates and transport relative to any potential exposure. There is no indication of whether there may be a human health factor associated with the deformities. However, the possibility that causal agents may be waterborne indicates a need to identify the relevant factors and establish the relationship between environmental and human health in terms of hazard assessment

Reconstructing mechanisms of extinctions to guide mammal conservation biogeography

First published: 07 April 2023. OnlinePublAn emerging research program on population and geographic range dynamics of Australia's mammals illustrates an approach to better understand and respond to geographic range collapses of threatened wildlife in general. In 1788, Europeans colonized an Australia with a diverse and largely endemic mammal fauna, where many species that are now extinct or threatened were common and widespread. Subsequent population declines, range collapses and extinctions were caused by introduced predators and herbivores, altered land use, modified fire regimes and the synergies between these threats. Declines in population and range size continue for many Australian mammals despite legislative protection and conservation interventions. Here, we propose an approach that integrates museum data and other historical records into process-explicit macroecological models to better resolve mammal distributions and abundances as they were at European arrival. We then illustrate how this integrative approach can identify the likely synergistic mechanisms causing mammal population declines across these and other landscapes. This emerging research approach, undertaken with fine temporal and spatial resolution, but at large geographic scales, will provide valuable insights into the different pathways to, and drivers of extinction. Such insights may, in turn, underpin conservation strategies based on a process-explicit understanding of population decline and range collapse under alternative scenarios of impending climate and environmental change. Given that similar information is available for other regional biotas, the approach we describe here can be adapted to conserve threatened wildlife in other regions across the globe.Sean Tomlinson, Mark V. Lomolino, John C. Z. Woinarski, Brett P. Murphy, Elizabeth Reed, Chris N. Johnson, Sarah Legge, Kristofer M. Helgen, Stuart C. Brown, Damien A. Fordha

Field Investigations of Malformed Frogs in Minnesota 1993-97

Reports of malformed frogs were made to the Minnesota Pollution Control Agency (MPCA) from different parts of Minnesota in 1993, 1995, 1996, and 1997 and one, nine, 190, and 172 reports were received, respectively. MPCA field crews and Drs. Hoppe and McKinnell documented malformed frog locations starting in 1993. By 1997, MPCA field crews documented malformed frogs at 62 locations in Minnesota, in 29 of 87 counties. Most malformations were in young metamorphs of Rana pipiens but they were observed also in R. clamitans, R. septentrionalis, R. sylvatica, Bufo americanus, and Hyla spp. Frequencies of malformations varied by time of year. Most malformations occurred in rear limbs, with some in front limbs, eye, jaw or skin. Frequencies of limb duplications at the Ney Pond were higher in 1995 (11.7%) than in subsequent years. Malformations were equally likely to be left- or right-sided. A study design in which malformed frog sites were paired with \u27reference\u27 sites was attempted, although some reference sites had, or developed, malformed frogs. In some sites, body weights of malformed metamorphs were significantly lower than normal ones, while in two sites both normal and abnormal metamorphs were quite reduced in size compared with frogs from reference sites. There is the possibility of a developmental delay in some of the metamorphs

Defining Anuran Malformations in the Context of a Developmental Problem

This paper summarizes terminology and general concepts involved in animal development for the purpose of providing background for the study and understanding of frog malformations. The results of our radiographic investigation of rear limb malformations in Rana pipiens provide evidence that frog malformations are the product of early developmental errors. Although bacteria, parasites and viruses were identified in these metamorphosed frogs, the relevant window to look for the teratogenic affect of these agents is in the early tadpole stage during limb development. As a result, our microbiological findings must be regarded as inconclusive relative to determining their contribution to malformations because we conducted our examinations on metamorphosed frogs not tadpoles. Future studies need to look at teratogenic agents (chemical, microbial, physical or mechanical) that are present in the embryo, tadpole, and their environments at stages of development that are relevant for the malformation type. The impact of these teratogenic agents then needs to be assessed in appropriate animal models using studies that are designed to mimic field conditions. The results of these laboratory tests should then be analyzed in such a way that will allow comparison with the findings in the wild-caught tadpoles and frogs