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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. To improve quantitative guidelines for taxonomic decisions in cetaceans, we build on a previous effort targeting the control region and evaluate, for whole mitogenome sequences, a suite of divergence and diagnosability estimates for pairs of recognized cetacean populations, subspecies, and species. From this overview, we recommend new guidelines based on complete mitogenomes, combined with other types of evidence for isolation and divergence, which will improve resolution for taxonomic decisions, especially in the face of small sample sizes or low levels of genetic diversity. We further use simulated data to assist interpretations of divergence in the context of varying forms of historical demography, culture, and ecology. [ABSTRACT FROM AUTHOR]

Three subspecies of fin whales (Balaenoptera physalus) are currently recognized, including the northern fin whale (B. p. physalus), the southern fin whale (B. p. quoyi), and the pygmy fin whale (B. p. patachonica). The Northern Hemisphere subspecies encompasses fin whales in both the North Atlantic and North Pacific oceans. A recent analysis of 154 mitogenome sequences of fin whales from these two ocean basins and the Southern Hemisphere suggested that the North Pacific and North Atlantic populations should be treated as different subspecies. Using these mitogenome sequences, in this study, we conduct analyses on a larger mtDNA control region data set, and on 23 single-nucleotide polymorphisms (SNPs) from 144 of the 154 samples in the mitogenome data set. Our results reveal that North Pacific and North Atlantic fin whales can be correctly assigned to their ocean basin with 99% accuracy. Results of the SNP analysis indicate a correct classification rate of 95%, very low rates of gene flow among ocean basins, and that distinct mitogenome matrilines in the North Pacific are interbreeding. These results indicate that North Pacific fin whales should be recognized as a separate subspecies, with the name B. p. velifera Cope in Scammon 1869 as the oldest available name. [ABSTRACT FROM AUTHOR]

The article offers information on the marine species condition at Upper Gulf of California. Topics discussed include concern for extinction of vaquita porpoise, most endangered marine mammal of Mexico; reduction of freshwater flow into the Upper Gulf of California (UGC) due to damming and diversion of the Colorado River, cause decline in vaquita; and collaborative efforts required among fishermen, the seafood supply chain, and environmental and fisheries agencies for conservative solution.

Genetic data are often critical for defining populations for management purposes (e.g., identifying geographic boundaries or diagnostic characters for genetically discrete subunits) but can be called into question by both scientific and legal review. This can result in reversed or delayed implementation of management actions. We discuss methods for data quality control and quality analysis and describe examples of steps applied to 2 of the most common types of genetic data, mitochondrial DNA sequences, and microsatellite genotypes. These steps can serve both as guides to conservation geneticists and as an initial protocol for managers to determine whether genetic data will hold up against legal and scientific challenges. In addition, we suggest types of data and quality measures that should be reported as supplementary materials to published reports. These supplementary data serve to reduce the occurrence of legal and conservation controversies and improve reproducibility over time in population genetics studies where genetic monitoring is likely to play an increasing role. [ABSTRACT FROM PUBLISHER]

In an open letter published in 2002 in the "New York Times", 21 distinguished scientists criticized Japan's program of scientific research whaling, noting its poor design and unjustified reliance upon lethal sampling. In a Forum article in "BioScience," Aron, Burke, and Freeman castigate the letter's signers and accuse them of meddling in political issues without sufficient knowledge of the science involved in those issues. As members of the Scientific Committee (SC) of the International Whaling Commission (IWC), we can attest that the signers of the open letter correctly summarized criticisms made by researchers very familiar with Japanese scientific whaling. One such critique was presented and discussed last year at a meeting of the SC. It was authored by SC members representing a broad range of countries, yet mention of this paper and others like it was absent from Aron and his colleagues' commentary, betraying a selectiveness that pervades their article. The authors quote lines from SC reports to support their contention that the IWC regards scientific whaling as valuable, but they fail to acknowledge many other sections that are highly critical of the Japanese program. Japan's scientific whaling program in the North Pacific (JARPN) was originally described as a feasibility study, but it included no performance measures by which to judge its success or failure. Fundamental problems of the JARPN II study include a lack of testable hypotheses or performance measures; inappropriate use of ecosystem models and failure to include sensitivity analyses and key data on other ecosystem components; selective or inappropriate use of data or methods in estimating whale abundance; unnecessary reliance on lethal sampling; inappropriate geographic sampling for population structure analysis; and unrealistic assessments of the effect of the proposed catches on the populations concerned.

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. Both mtDNA and nucDNA exhibit highly significant differentiation between populations, confirming limited gene flow in both sexes. The mtDNA haplotypes exhibit a strong pattern of phylogeographic concordance, with island-associated populations sharing 3 closely related haplotypes not found elsewhere in the Pacific. However, nucDNA data suggest that NWHI animals are at least as differentiated from MHI animals as they are from offshore animals. The patterns of differentiation revealed by the 2 marker types suggest that the island-associated false killer whale populations likely share a common colonization history, but have limited contemporary gene flow. [ABSTRACT FROM PUBLISHER]