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Beth Shapiro

Publications and source records attributed to Beth Shapiro.

7 recordsLinked to original sources

Phylogenomics and museomics reveal five distinct species of tiger cats in South America.

The evolutionary history of elusive organisms can be characterized through genomic analyses, which have the power to reveal previously unknown taxa even in groups assumed to be well studied, such as cats. We have analyzed complete genomes of 38 individuals from the Neotropical cat genus Leopardus, including 26 individuals representing multiple evolutionary units of the contentious tiger cat (Leopardus tigrinus) species complex. Eight genomes were generated from museum specimens, which allowed the first genetic assessment of the type locality for L. tigrinus in the Guiana Shield. We found that this complex comprises five distinct species, including a novel cat species, discovered in the Bolivian Yungas and described in this study as L. tilcayo. The Peruvian Yungas unit of this complex also represents a distinct taxonomic entity, which we describe here as a novel subspecies, L. tigrinus antisuyo. Our phylogenomic analyses resolve the evolutionary relationships among the tiger cat geographic units, thus stabilizing their recalcitrant taxonomy and enabling adequate conservation assessment of these threatened felids. We also address other aspects of their evolution, including biogeography, past episodes of interspecies admixture, demographic history of each taxonomic unit, and temporal changes in genetic diversity. Altogether, our results clarify the evolutionary history of a complex radiation of wild cats, reveal novel taxa, and serve as a basis for conservation planning on behalf of these elusive wild cats.

Bolivian Yungas

A chromosome-level genome of the Nicobar pigeon, Caloenas nicobarica.

The Nicobar pigeon (Caloenas nicobarica), the closest living relative of the extinct Dodo (Raphus cucullatus), is endemic to Southeast Asia with a fragmented distribution across numerous small islands. It suffers from habitat loss, hunting, and predation from invasive species, resulting in its classification as Near Threatened by the International Union for the Conservation of Nature. We have generated a haplotype-resolved and chromosome-level genome assembly of the Nicobar pigeon using a combination of PacBio HiFi long-read sequencing and Arima Hi-C chromatin interaction mapping. This assembly includes two haplotypes, each spanning approximately 1.2 Gb. Haplotype 1 has a contig N50 of 25.2 Mb and a scaffold N50 of 79.7 Mb, whereas haplotype 2 has a contig N50 of 24.7 Mb and a scaffold N50 of 107.9 Mb. As the first high-quality genome assembly of any bird in the Columbidae Indo-Pacific clade, this resource provides valuable insights for phylogenetic studies. Furthermore, the phylogenetic proximity of the Nicobar pigeon to the Dodo (R. cucullatus) and the Rodrigues Solitaire (Pezophaps solitaria) offers a unique opportunity to study these extinct species, making this assembly a critical resource for evolutionary studies. It also offers a unique model for studying genetic diversity, adaptation, and speciation in island environments. This genomic resource will not only enhance our understanding of the evolutionary history of the Nicobar pigeon but also serve as a valuable tool for future conservation efforts aimed at preserving this unique species and its fragile island ecosystem.

Animals

De-extinction technology and its application to conservation.

De-extinction, once the realm of science fiction, has evolved into a tangible scientific endeavor thanks to breakthroughs in genome sequencing, engineering, advanced assisted reproductive technologies, and stem cell biology. Alongside this work are innovations in reintroduction science and artificial intelligence, which are refining strategies for species translocations, rewilding, and long-term ecosystem monitoring of de-extinct species and populations. While the primary motivation for de-extinction is restoring lost ecological functions to eroded ecosystems, each of these technologies can also be applied to conservation biology for de-endangerment, offering new solutions for biodiversity preservation. This review synthesizes the technological advancements emerging from de-extinction science and explores their broad applications in conservation, demonstrating how de-extinction is both about resurrecting lost species and about expanding the conservation toolkit to sustain and rebuild biodiversity in the face of accelerating environmental change.

Conservation of Natural Resources

Rapid derivation of cloning-competent cells from peripheral blood advances conservation biobanking.

Establishing viable cell lines from endangered species is essential for conservation, yet traditional fibroblast derivation from skin biopsies faces challenges including contamination risk and extended culture timelines. Here, we demonstrate that endothelial progenitor cells (EPCs) and pericytes isolated from peripheral blood represent robust alternatives to fibroblasts for biobanking. Compared to canid fibroblasts, canid blood-derived cells exhibit 2- to 3-fold faster doubling rates (15 to 20 h vs. ~35 h for fibroblasts) and reduced time to banked cell lines (1.5 to 2 wks vs. 3 to 4 wks for fibroblasts). Proteomic profiling of 32 canonical markers confirmed EPCs and pericytes represent distinct populations with lineage-specific molecular signatures. Optical genome mapping demonstrated equivalent genomic stability across cell types with no detectable structural variants or aneuploidies. Finally, interspecific somatic cell nuclear transfer (iSCNT) experiments confirmed both EPCs and pericytes generate viable canid embryos with efficiency meeting or exceeding fibroblasts. As a proof of concept for conservation cloning, iSCNT embryos made with gray wolf blood-derived cells had a 15% implantation rate following embryo transfer and resulted in six viable fetuses. These findings support integrating blood-derived cell banking into conservation programs, which enables opportunistic genetic preservation during standard management activities and expands options for genetic rescue through assisted reproductive technologies.

Animals

Paleogenomic sex inference of mammoth remains sheds light on the anthropogenic nature of bone accumulations.

Whether large accumulations of woolly mammoth (Mammuthus primigenius) bones reflect natural mortality or deliberate human resource exploitation has long been debated, with major implications for understanding Late Pleistocene human-megafaunal interactions.1,2,3,4,5 Here, we use ancient DNA to investigate site-formation hypotheses by comparing genetic sex ratios from mammoth remains recovered in putative anthropogenic bone accumulations and from geographically dispersed, non-anthropogenic contexts. We studied genome-wide data from 521 woolly mammoths-including 100 mammoths from bone accumulation sites and 421 mammoths from natural depositional settings across Eurasia and North America-of which 448 are newly generated. Genetic sex determination reveals a striking contrast between contexts: mammoths from dispersed sites show a male bias (∼66.5%), which is consistent with the heightened vulnerability of solitary males to hazards such as natural traps, where bones are more likely to be preserved, whereas mammoths from anthropogenic bone accumulations are predominantly female (∼70%). This female bias is pervasive across multiple sites, indicating an anthropogenic origin for these accumulations as a result of Upper Paleolithic hunters preferentially exploiting female mammoths, possibly derived from herd contexts. Together, these results provide population-scale genetic evidence that highlights the central role of mammoths in the subsistence and material economies of some Paleolithic communities.

Animals

Recent Adaptation in a Threatened Salmonid Revealed by Museum Genomics.

Steelhead/rainbow trout (Oncorhynchus mykiss) is an imperilled salmonid with two main life history strategies: migrate to the ocean or remain in freshwater. Domesticated hatchery forms of this species have been stocked into almost all California waterways, possibly resulting in introgression into natural populations and altered population structure. We compared whole-genome sequence data from contemporary populations against a set of museum population samples of steelhead from the same locations that were collected prior to most hatchery stocking. We observed minimal introgression and few steelhead-hatchery trout hybrids despite a century of extensive stocking. Our historical data show signals of introgression with a sister species and indications of an early hatchery facility. Finally, we found that migration-associated haplotypes have become less frequent over time, a likely adaptation to decreased opportunities for migration. Since contemporary migration-associated haplotype frequencies have been used to guide species management, we consider this to be a rare example of shifting baseline syndrome that has been validated with historical data. We suggest cautious optimism that a century of hatchery stocking has had minimal impact on California steelhead population genetic structure, but we note that continued shifts in life history may lead to further declines in the ocean-going form of the species.

Animals

Persistent Genomic Erosion in Whooping Cranes Despite Demographic Recovery.

Integrating in-situ (wild) and ex-situ (captive) conservation efforts can mitigate genetic diversity loss and help prevent extinction of endangered wild populations. The whooping crane (Grus americana) experienced severe population declines in the 18th century, culminating in a collapse to ~20 individuals by 1944. Legal protections and conservation actions have since increased the census population from a stock of 16 individuals to approximately 840 individuals, yet the impact on genomic diversity remains unclear. We analysed the temporal dynamics of genomic erosion by sequencing a high-quality reference genome, and re-sequencing 16 historical (years 1867-1893) and 37 modern (2007-2020) genomes, including wild individuals and four generations of captive-bred individuals. Genomic demographic reconstructions reveal a steady decline, accelerating over the past 300 years with the European settlement of North America. Temporal genomic analyses show that despite demographic recovery, the species has lost 70% of its historical genetic diversity and has increased its inbreeding. Although the modern population bottleneck reduced the ancestral genetic load, modern populations possess more realised load than masked load, possibly resulting in a chronic loss of fitness. Integrating pedigree and genomic data, we underscore the role of breeding management in reducing recent inbreeding. Yet ongoing heterozygosity loss, load accumulation, and persistent effects of historical inbreeding (i.e., background inbreeding) argue against the species' downlisting from its current Endangered status on the IUCN Red List and the Endangered Species Act. The presence of private genetic variation in wild and captive populations suggests that wild-captive crosses could enhance genetic diversity and reduce the realised load. Our findings emphasise the role of genomics in informing conservation management and policy.

Animals