Knowledge of genetic diversity and population structure is critical for conservation and management planning at the population level within a species’ range. Many brown bear populations in Central Asia are small and geographically isolated, yet their phylogeographic relationships, genetic diversity, and contemporary connectivity are poorly understood. To address this knowledge gap, we collected brown bear samples from the Gobi Desert (n = 2360), Altai, Sayan, Khentii, and Ikh Khyangan mountains of Mongolia (n = 79), and Deosai National Park in the Himalayan Mountain Range of Pakistan (n = 5) and generated 927 base pairs of mitochondrial DNA (mtDNA) sequence data and genotypes at 13 nuclear DNA microsatellite loci. We documented high levels of mtDNA and nDNA diversity in the brown bear populations of northern Mongolia (Altai, Sayan, Buteeliin nuruu and Khentii), but substantially lower diversity in brown bear populations in the Gobi Desert and Himalayas of Pakistan. We detected 3 brown bear mtDNA phylogeographic groups among bears of the region, with clade 3a1 in Sayan, Khentii, and Buteeliin nuruu mountains, clade 3b in Altai, Sayan, Buteeliin nuruu, Khentii, and Ikh Khyangan, and clade 6 in Gobi and Pakistan. Our results also clarified the phylogenetic relationships and divergence times with other brown bear mtDNA clades around the world. The nDNA genetic structure analyses revealed distinctiveness of Gobi bears and different population subdivisions compared to mtDNA results. For example, genetic distance for nDNA microsatellite loci between the bears in Gobi and Altai (F_ST = 0.147) was less than that of the Gobi and Pakistan (F_ST = 0.308) suggesting more recent male-mediated nuclear gene flow between Gobi and Altai than between Gobi and the Pakistan bears. Our results provide valuable information for conservation and management of bears in this understudied region of Central Asia and highlight the need for special protection and additional research on Gobi brown bears.

Background: Mesophotic coral communities are increasingly gaining attention for the unique biological diversity they host, exemplified by the numerous mesophotic fish species that continue to be discovered. In contrast, many of the photosynthetic scleractinian corals observed at mesophotic depths are assumed to be depth-generalists, with very few species characterised as mesophotic-specialists. This presumed lack of a specialised community remains largely untested, as phylogenetic studies on corals have rarely included mesophotic samples and have long suffered from resolution issues associated with traditional sequence markers. Results: Here, we used reduced-representation genome sequencing to conduct a phylogenomic assessment of the two dominant mesophotic genera of plating corals in the Indo-Pacific and Western Atlantic, respectively, Leptoseris and Agaricia. While these genome-wide phylogenies broadly corroborated the morphological taxonomy, they also exposed deep divergences within the two genera and undescribed diversity across the current taxonomic species. Five of the eight focal species consisted of at least two sympatric and genetically distinct lineages, which were consistently detected across different methods. Conclusions: The repeated observation of genetically divergent lineages associated with mesophotic depths highlights that there may be many more mesophotic-specialist coral species than currently acknowledged and that an urgent assessment of this largely unstudied biological diversity is warranted.

What we mean by species and whether they have any biological reality has been debated since the early days of evolutionary biology. Some biologists even suggest that plant species are created by taxonomists as a subjective, artificial division of nature. However, the nature of plant species has been rarely tested critically with data while ignoring taxonomy. We integrate phenomic and genomic data collected across hundreds of individuals at a continental scale to investigate this question inEscallonia(Escalloniaceae), a group of plants which includes 40 taxonomic species (the species proposed by taxonomists). We first show that taxonomic species may be questionable as they match poorly to patterns of phenotypic and genetic variation displayed by individuals collected in nature. We then use explicit statistical methods for species delimitation designed for phenotypic and genomic data, and show that plant species do exist inEscalloniaas an objective, discrete property of nature independent of taxonomy. We show that such species correspond poorly to current taxonomic species ( $$< 20\%$$<20% ) and that phenomic and genomic data seldom delimit congruent entities ( $$< 20\%$$<20% ). These discrepancies suggest that evolutionary forces additional to gene flow can maintain the cohesion of species. We propose that phenomic and genomic data analyzed on an equal footing build a broader perspective on the nature of plant species by helping delineate different ‘types of species’. Our results caution studies which take the accuracy of taxonomic species for granted and challenge the notion of plant species without empirical evidence. Note: A version of the complete manuscript in Spanish is available in the Supplemental Materials.

Sandblossoms, Linanthus parryae is a widespread annual plant species found in washes and sandy open habitats across the Mojave Desert and Eastern Sierra Nevada of California. Studies in this species have played a central role in evolutionary biology, serving as the first test cases of the shifting balance theory of evolution, models of isolation by distance, and metrics to describe the genetic structure of natural populations. Despite the importance of L. parryae in the development of landscape genetics and phylogeography, there are no genomic resources available for the species. Through the California Conservation Genomics Project, we assembled the first genome in the genus Linanthus. Using PacBio HiFi long reads and Hi-C chromatin conformation capture, we assembled 123 scaffolds spanning 1.51 Gb of the 1.96 Gb estimated genome, with a contig N50 of 18.7 Mb and a scaffold N50 of 124.8 Mb. This assembly, with a BUSCO completeness score of 88.7%, will allow us to revisit foundational ideas central to our understanding of how evolutionary forces operate in a geographic landscape. In addition, it will be a new resource to uncover adaptations to arid environments in the fragile desert habitat threatened by urban and solar farm development, climate change, and off-road vehicles.

Summary: Digitized herbarium specimens and iNaturalist observations provide invaluable plant biodiversity data. Combining these two data sources could create a more holistic representation of local biodiversity; however, understanding biases inherent to each is critical to determine how to best combine and utilize these data. We examined how the interpretation of taxonomic and phylogenetic diversity, naturalized species detection, and spatiotemporal coverage differ when using herbarium and iNaturalist data alone and together. We also examined how these patterns vary among areas with different degrees of collecting and community science efforts. Across areas, diversity was higher when data sources were combined, and complementary spatiotemporal coverage between data sources indicates that combining these data is useful; however, biases unique to each data source should be considered during analyses. Naturalized species detection, diversity patterns, and spatial biases varied by area, indicating that local context impacts our current views of biodiversity and should shape future monitoring. Our findings suggest that continued digitization and georeferencing of the herbarium records will help provide critical information about biodiversity, but a strategic collection of both specimens and iNaturalist observations moving forward will ensure that we are capturing biodiversity change in real time, helping us track responses to environmental change.