Publications by authors named "Frederick Archer"

The bottlenose dolphin is a widely distributed species found in temperate waters, including the Mediterranean and Black Seas. The Black Sea population is recognized as a distinct subspecies, , due to genetic and morphological differences. This study analyzed mitochondrial DNA (mtDNA) sequences of 73 bottlenose dolphin samples collected between 1999 and 2016 along the Turkish Black Sea coast, Turkish Straits System (TSS), Aegean, and Mediterranean Seas revealing 14 haplotypes, eight of which are reported here for the first time.

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  • * The study specifically focuses on two ecotypes in the eastern North Pacific: the resident and Bigg's (transient) killer whales, assessing their ecological roles, physical traits, and genetic data.
  • * Findings support classifying both ecotypes as separate species, suggesting that Bigg's killer whales and resident killer whales should receive distinct taxonomic recognition.
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Twentieth century industrial whaling pushed several species to the brink of extinction, with fin whales being the most impacted. However, a small, resident population in the Gulf of California was not targeted by whaling. Here, we analyzed 50 whole-genomes from the Eastern North Pacific (ENP) and Gulf of California (GOC) fin whale populations to investigate their demographic history and the genomic effects of natural and human-induced bottlenecks.

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In many organisms, especially those of conservation concern, traditional lines of evidence for taxonomic delineation, such as morphological data, are often difficult to obtain. In these cases, genetic data are often the only source of information available for taxonomic studies. In particular, population surveys of mitochondrial genomes offer increased resolution and precision in support of taxonomic decisions relative to conventional use of the control region or other gene fragments of the mitochondrial genome.

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The 20th century commercial whaling industry severely reduced populations of great whales throughout the Southern Hemisphere. The effect of this exploitation on genetic diversity and population structure remains largely undescribed. Here, we compare pre- and post-whaling diversity of mitochondrial DNA (mtDNA) control region sequences for 3 great whales in the South Atlantic, such as the blue, humpback, and fin whale.

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  • Parallel evolution shows how species adapt to different environments through natural selection, but there's still debate about how and when it happens.
  • Using paleogenomics, researchers analyzed genomes from ancient bottlenose dolphins to see how closely linked they are to today's coastal populations.
  • They discovered that more recent genomes contain genetic variants associated with coastal habitats, revealing a shared genetic history that helped these dolphins adapt quickly to changing environments.
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Cetaceans have shown a potential to be used as sentinel species for tracking environmental change in marine ecosystems, yet our assessment of change is typically limited to recent decades and lacks ecological baselines. Using historical museum specimens, we compared community niche metrics and degree of individual dietary specialization in groups of Pacific Arctic beluga () from the 1800s ( = 5) to 1900s ( = 10) using stable carbon and nitrogen isotopes drilled from teeth. Beluga occupied a broader trophic niche and demonstrated a higher degree of individual specialization in the 1800s than in the 1900s.

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  • - Fin whales faced unsustainable hunting practices in the 19th and 20th centuries, especially in the Southern Ocean, resulting in a dramatic decline in their population, with around 730,000 harvested in the Southern Hemisphere alone.
  • - Researchers utilized historical samples like bones and baleen from ex-whaling stations and museums to investigate the genetic diversity and population structure of Southern Hemisphere fin whales around the time of whaling.
  • - The analysis of 27 historical mitogenomes and additional genetic data revealed that Southern Hemisphere fin whales are highly diverse and potentially represent a single interconnected population, distinct from their Northern Hemisphere counterparts, marking the first availability of historic genomic data for these whales.
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  • * The Group on Earth Observations Biodiversity Observation Network (GEO BON) developed Essential Biodiversity Variables (EBVs), which are key metrics to standardize biodiversity data and help evaluate geographical distribution and changes over time.
  • * The text focuses on implementing Genetic Composition EBVs, assessing genetic variation within species, and proposes four specific Genetic EBVs while discussing their relevance and the processes needed for effective data generation and archiving.
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Belugas (Delphinapterus leucas) and narwhals (Monodon monoceros) are highly social Arctic toothed whales with large vocal repertoires and similar acoustic profiles. Passive Acoustic Monitoring (PAM) that uses multiple hydrophones over large spatiotemporal scales has been a primary method to study their populations, particularly in response to rapid climate change and increasing underwater noise. This study marks the first acoustic comparison between wild belugas and narwhals from the same location and reveals that they can be acoustically differentiated and classified solely by echolocation clicks.

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  • Studying repeated adaptation helps us understand how species like dolphins can adjust to different environments over time.
  • The research focuses on the common bottlenose dolphin, examining how distinct groups in coastal and pelagic habitats have evolved separately across the world.
  • An analysis of 57 dolphin genomes reveals that adaptations occurred through a complex history of evolution, highlighting how ancient genetic variations played a role in these adaptations despite challenges like small population sizes.
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The health of the world's oceans is intrinsically linked to the biodiversity of the ecosystems they sustain. The importance of protecting and maintaining ocean biodiversity has been affirmed through the setting of the UN Sustainable Development Goal 14 to conserve and sustainably use the ocean for society's continuing needs. The decade beginning 2021-2030 has additionally been declared as the UN Decade of Ocean Science for Sustainable Development.

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The vaquita is the most critically endangered marine mammal, with fewer than 19 remaining in the wild. First described in 1958, the vaquita has been in rapid decline for more than 20 years resulting from inadvertent deaths due to the increasing use of large-mesh gillnets. To understand the evolutionary and demographic history of the vaquita, we used combined long-read sequencing and long-range scaffolding methods with long- and short-read RNA sequencing to generate a near error-free annotated reference genome assembly from cell lines derived from a female individual.

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In the California Current off the United States West Coast, there are three offshore cetacean species that produce narrow-band high frequency (NBHF) echolocation pulses: Dall's porpoise (Phocoenoides dalli) and two species of Kogia. NBHF pulses exist in a highly specialized acoustic niche thought to be outside the hearing range of killer whales and other potential mammal-eating odontocetes. Very little is known about the dwarf and pygmy sperm whales (K.

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Theory suggests that the direct transmission of beneficial endosymbionts (mutualists) from parents to offspring (vertical transmission) in animal hosts is advantageous and evolutionarily stable, yet many host species instead acquire their symbionts from the environment (horizontal acquisition). An outstanding question in marine biology is why some scleractinian corals do not provision their eggs and larvae with the endosymbiotic dinoflagellates that are necessary for a juvenile's ultimate survival. We tested whether the acquisition of photosynthetic endosymbionts (family Symbiodiniaceae) during the planktonic larval stage was advantageous, as is widely assumed, in the ecologically important and threatened Caribbean reef-building coral Orbicella faveolata.

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Genetic monitoring estimates temporal changes in population parameters from molecular marker information. Most populations are complex in structure and change through time by expanding or contracting their geographic range, becoming fragmented or coalescing, or increasing or decreasing density. Traditional approaches to genetic monitoring rely on quantifying temporal shifts of specific population metrics-heterozygosity, numbers of alleles, effective population size-or measures of geographic differentiation such as .

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We compare the two main classes of measures of population structure in genetics: (i) fixation measures such as ,, and θ and (ii) allelic differentiation measures such as Jost's and entropy differentiation. These two groups of measures quantify complementary aspects of population structure, which have no necessary relationship with each other. We focus especially on empirical aspects of population structure relevant to conservation analyses.

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Many dinoflagellate microalgae of the genus Symbiodinium form successful symbioses with a large group of metazoans and selected protists. Yet knowledge of growth kinetics of these endosymbionts and their ecological and evolutionary implications is limited. We used a Bayesian biphasic generalized logistic model to estimate key parameters of the growth of five strains of cultured Symbiodinium, S.

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Untargeted metabolomics of environmental samples routinely detects thousands of small molecules, the vast majority of which cannot be identified. Meta-mass shift chemical (MeMSChem) profiling was developed to identify mass differences between related molecules using molecular networks. This approach illuminates metabolome-wide relationships between molecules and the putative chemical groups that differentiate them (e.

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Simulations are a key tool in molecular ecology for inference and forecasting, as well as for evaluating new methods. Due to growing computational power and a diversity of software with different capabilities, simulations are becoming increasingly powerful and useful. However, the widespread use of simulations by geneticists and ecologists is hindered by difficulties in understanding these softwares' complex capabilities, composing code and input files, a daunting bioinformatics barrier and a steep conceptual learning curve.

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Genetic sequences of multiple genes are becoming increasingly common for a wide range of organisms including viruses, bacteria and eukaryotes. While such data may sometimes be treated as a single locus, in practice, a number of biological and statistical phenomena can lead to phylogenetic incongruence. In such cases, different loci should, at least as a preliminary step, be examined and analysed separately.

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We introduce the r package stratag as a user-friendly population genetics toolkit. stratag provides easy access to a suite of standard genetic summaries as well as the ability to rapidly manipulate stratified genetic data for custom analyses. Tests of population subdivision with most common measures of population subdivision (e.

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Global climate change during the Late Pleistocene periodically encroached and then released habitat during the glacial cycles, causing range expansions and contractions in some species. These dynamics have played a major role in geographic radiations, diversification and speciation. We investigate these dynamics in the most widely distributed of marine mammals, the killer whale (Orcinus orca), using a global data set of over 450 samples.

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Microorganisms in terrestrial and marine ecosystems are essential to environmental sustainability. In the marine environment, invertebrates often depend on metabolic cooperation with their endosymbionts. Coral reefs, one of the most important marine ecosystems, are based on the symbiosis between a broad diversity of dinoflagellates of the genus Symbiodinium and a wide phyletic diversity of hosts (i.

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False killer whales (Pseudorca crassidens) are large delphinids typically found in deep water far offshore. However, in the Hawaiian Archipelago, there are 2 resident island-associated populations of false killer whales, one in the waters around the main Hawaiian Islands (MHI) and one in the waters around the Northwestern Hawaiian Islands (NWHI). We use mitochondrial DNA (mtDNA) control region sequences and genotypes from 16 nuclear DNA (nucDNA) microsatellite loci from 206 individuals to examine levels of differentiation among the 2 island-associated populations and offshore animals from the central and eastern North Pacific.

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