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The great whales (baleen and sperm whales), through their massive size and wide distribution, influence ecosystem and carbon dynamics. Whales directly store carbon in their biomass and contribute to carbon export through sinking carcasses. Whale excreta may stimulate phytoplankton growth and capture atmospheric CO

The sunken carcasses of great whales (i.e., whale falls) provide an important deep-sea habitat for more than 100 species that may be considered whale-fall specialists. Commercial whaling has reduced the abundance and size of whales, and thus whale-fall habitats, as great whales were hunted and removed from the oceans, often to near extinction. In this article, we use a metapopulation modeling approach to explore the consequences of whaling to the abundance and persistence of whale-fall habitats in the deep sea and to the potential for extinction of whale-fall specialists. Our modeling indicates that the persistence of metapopulations of whale-fall specialists is linearly related to the abundance of whales, and extremely sensitive (to the fourth power) to the mean size of whales. Thus, whaling-induced declines in the mean size of whales are likely to have been as important as declines in whale abundance to extinction pressure on whale-fall specialists. Our modeling also indicates that commercial whaling, even under proposed sustainable yield scenarios, has the potential to yield substantial extinction of whale-fall specialists. The loss of whale-fall habitat is likely to have had the greatest impact on the diversity of whale-fall specialists in areas where whales have been hunted for centuries, allowing extinctions to proceed to completion. The North Atlantic experienced dramatic declines, and even extirpation, of many whale species before the 20th century; thus, extinctions of whale-fall specialists are likely to have already occurred in this region. Whale depletions have occurred more recently in the Southern Hemisphere and across most of the North Pacific; thus, these regions may still have substantial "extinction debts," and many extant whale-fall specialists may be destined for extinction if whale populations do not recover in abundance and mean size over the next few decades. Prior to the resumption of commercial whaling, or the loosening of protections to reduce incidental take, the impacts of hunting on deep-sea whale-fall ecosystems, as well as differential protection of the largest whales within and across species, should be carefully considered.

Physical disruption of an ecosystem by sea otters affects the genetic diversity of their habitat

Key improvements are needed for implementation of the Endangered Species Act

Humans and natural systems face three pressing concerns: the loss of large animal biodiversity, eutrophication of many aquatic systems, and the need to better recycle phosphorus. Here we propose a mechanism to help alleviate these problems. Some have hypothesized that we are approaching “peak phosphorus,” where phosphorus may become more expensive as it becomes rarer, thus endangering the green agricultural revolution and the ability to feed ourselves. Animals play a key role in the recycling of phosphorus (P) from the ocean depths to the continental interiors, but this movement has declined by >90% over the past 10,000 years. Prior to this decline, animals played a critical role in the global P budget and the pre-Anthropocene P budget was in steady state only after accounting for animal P inputs. Recently a 5R strategy was developed by Withers et al (2015) to Realign P inputs, Reduce P losses, Recycle P in bio-resources, Recover P in wastes, and Redefine P in food systems. Here we suggest a sixth R, to Revitalize the natural phosphorus pump. Countries are starting to mandate P recycling, and here we propose a P-trading scheme based on REDD+, where a country could partially achieve its recycling goals through revitalizing the natural P pump. Accrued money from this scheme could be used to restore or conserve wild animal populations while increasing natural phosphorus recycling.

Post-print (lokagerð höfundar), Although whale ecosystem services have been scarcely explored in the academic literature, they illustrate many of the threats, trade-offs and decision-making dilemmas common to marine ecosystem services in general – climate change impacts, the ongoing need to provide remote communities with forms of sustenance, and the potential development of new economic sectors which are prosperous but undermine traditional ways of life. In this paper, the first evaluation is carried out of the ecosystem services specific to whales, involving (a) their classification using the established Common International Classification Ecosystem Services (CICES) framework, (b) an assessment of the most suitable methods for their valuation, and (c) implications for decision-making. Our findings are that whale ecosystem services belong to all three categories of the CICES classification and cultural services are the most common type. The most suitable approach for the respective valuation of each service depends on the local socio-cultural context, a fundamental ingredient in value formation, which can formulate on either an individual or collective basis. In the case of individual value formation, this paper recommends the use of economic information derived from non-market valuation techniques; for collective, non-monetary techniques are advised. Given the complexity of human-environment interactions, a pluralist approach to valuation is likely to be required, whereby decision-makers are informed about impacts to whale ecosystem services through a mixture of economic and non-monetary information. A logical consequence of value pluralism is the need for decision-support platforms which can satisfactorily integrate different types of information concerning ecosystem service impacts, evaluating these against multiple marine management objectives. The paper briefly reflects on the potential of Multi-Criteria Decision Analysis to fulfil this ambition, before discussing some of the current challenges and barriers which have limited the uptake of ecosystem services research in marine planning and decision-making., This paper has been funded by NordForsk (grant number 76654) via their financial support to the Nordic Centre of Excellence ARCPATH (Arctic Climate Predictions – Pathways to Resilient, Sustainable Communities).

Two genetically distinct lineages of European green crabs (Carcinus maenas) were independently introduced to eastern North America, the first in the early 19th century and the second in the late 20th century. These lineages first came into secondary contact in southeastern Nova Scotia, Canada (NS), where they hybridized, producing latitudinal genetic clines. Previous studies have documented a persistent southward shift in the clines of different marker types, consistent with existing dispersal and recruitment pathways. We evaluated current clinal structure by quantifying the distribution of lineages and fine‐scale hybridization patterns across the eastern North American range (25 locations, ~39 to 49°N) using informative single nucleotide polymorphisms (SNPs; n = 96). In addition, temporal changes in the genetic clines were evaluated using mitochondrial DNA and microsatellite loci (n = 9–11) over a 15‐year period (2000–2015). Clinal structure was consistent with prior work demonstrating the existence of both northern and southern lineages with a hybrid zone occurring between southern New Brunswick (NB) and southern NS. Extensive later generation hybrids were detected in this region and in southeastern Newfoundland. Temporal genetic analysis confirmed the southward progression of clines over time; however, the rate of this progression was slower than predicted by forecasting models, and current clines for all marker types deviated significantly from these predictions. Our results suggest that neutral and selective processes contribute to cline dynamics, and ultimately, highlight how selection, hybridization, and dispersal can collectively influence invasion success.

The many values that humans place on biodiversity are widely acknowledged but difficult to measure in practice. We address this problem by quantifying the contribution of marine-related environmental stewardship, in the form of donations and volunteer hours, to the economy of coastal Massachusetts. Our conservative evaluation suggests that marine stewardship activities contributed at least $179 million to the state economy in 2014, a figure that exceeded revenues derived in that same year from commercial finfish operations ($105 million) and whale watching ($111 million), two acknowledged cornerstones of the regional economy. Almost imperceptibly, the coastal economy has been transformed from one dependent on commercial exchange to a diverse economy that includes, to a large measure, marine stewardship. Donations and volunteer efforts are useful indicators of environmental values that can be hard to quantify, and represent one measure of human determination to protect the planet.

Cuba has a long history of environmental protection, with a network of more than 250 national parks and protected areas, and relatively high levels of fish biomass and marine biodiversity in marine parks that are unparalleled in the Caribbean. There is concern that the normalization of relations between the United States and Cuba might reverse the country’s advances in ecological conservation. In this chapter, I propose an approach to protect Cuba’s coastal ecosystems and enhance conservation and ecological research throughout the Caribbean. After helping Cuba fight for independence from Spain, the United States occupied the island in 1898. As part of the Cuban-American Treaty, which granted Cuba independence in 1902, the new country was required to rent Guantanamo Bay to the United States as a coaling and naval station, a perpetual lease that could be broken only by mutual consent. The present U.S. policy is that withdrawal from the base is not an option. Cuba insists on an unconditional return of the land as part of normalization. There is a third path that would benefit Cuba, the United States, and the rest of the world. Once the military prison at U.S. Naval Station Guantanamo Bay is closed, the entire base should be repurposed into a state-of-the-art research institution and peace park, a conservation zone to help resolve conflicts between the two countries. A first step in returning the land to Cuba, this model could unite both nations in joint management, rather than serve as a wedge between them. By bringing together Cuban, U.S., and international scientists, artists, and scholars, Guantanamo could help all countries meet the challenges of climate change, mass extinction, and declining coral reefs.

Commercial whaling is a divisive issue in Iceland, and often considered to be irreconcilable with whale watching. The coexistence of both activities in Faxafloi Bay, adjacent to the capital city of Reykjavik, has led to the designation of part of the bay as a whale sanctuary, where whaling is banned. The study utilises the contingent valuation method to elicit the preferences of Icelanders and estimate their willingness to pay (WTP) to expand the sanctuary to the full extent of Faxafloi Bay, with an aim to inform marine spatial planning in Iceland. Using the double-bounded dichotomous approach, the mean WTP for expansion of the Faxafloi Bay Whale Sanctuary was estimated to be 5082 ISK/42 USD per person (1.32 billion ISK/10.9 million USD when multiplied by the number of taxpayers), and 29.7% of the respondents with clearly defined preferences expressed positive WTP. According to the logit regression model, statistically significant socioeconomic and attitudinal variables included age, gender, level of education, number of persons in a household, and attitudes towards environmental conservation and whaling. Policy implications of non-market valuation of marine ES are discussed, pointing to a need to further assess the multiple marine ES values applying a transdisciplinary approach to inform decision-making.

Post-print (lokagerð höfundar), Goal 14, ‘Life Below Water’, of the United Nations Sustainable Development Goals sets a target for nations to increase the number of marine protected areas managed using ecosystem-based management, which requires interventions focused on fish stock conservation and enhancement, environmental sustainability and ecosystem services of benefit to human beings. Although not adhering to the International Union for Conservation of Nature's criteria for marine protected areas, whale sanctuaries are an increasingly common approach to conservation around the world. This paper is the first in the academic literature to use a case study approach to review the extent to which whale sanctuaries contribute to ecosystem-based management. A fifteen-criteria framework for marine ecosystem-based management is applied with reference to six whale sanctuary case studies, including the International Whaling Commission's two designations in the Indian Ocean and Southern Ocean. The review underscores the generally very limited contribution of whale sanctuaries to ecosystem-based management, unless they are explicit in stating conservation goals and embedding these within iterative management plans. The Hawaiian Islands Humpback Whale National Marine Sanctuary is cited as an example of an approach that comes closest to fulfilling the objectives of ecosystem-based management, albeit its designation lacks consideration of ecosystem dynamics and the interrelationships between multiple economic actors operating within its boundaries. In order to meet the requirements of Goal 14, the case studies in this paper reveal advancements necessary for whale sanctuaries to transition towards ecosystem-based management: establishment of objectives broader than the conservation of whale stocks, assessment of the contribution of the sanctuary to human well-being and trade-offs in ecosystem services, accounting for ecological and socio-economic dynamics, and ensuring broad stakeholder consultation and participatory adaptive management., This paper has been funded by NordForsk (grant number 76654) via their financial support to the Nordic Centre of Excellence ARCPATH (Arctic Climate Predictions – Pathways to Resilient, Sustainable Communities).

Rumen microorganisms are the origin of many bioactive fatty acids (FA) found in ruminant-derived food products. Differences in plant leaf anatomy and chemical composition between cool- and warm-season pastures may alter rumen microorganisms, potentially enhancing the quantity/profile of bioactive FA available for incorporation into milk. The objective of this study was to identify rumen bacteria and protozoa and their cellular FA when cows grazed a warm-season annual, pearl millet (PM), in comparison to a diverse cool-season pasture (CSP). Individual rumen digesta samples were obtained from five Holstein cows in a repeated measures design with 28-day periods. The treatment sequence was PM, CSP, then PM. Microbial DNA was extracted from rumen digesta and sequence reads were produced with Illumina MiSeq. Fatty acids (FA) were identified in rumen bacteria and protozoa using gas-liquid chromatography/mass spectroscopy. Microbial communities shifted in response to grazing regime. Bacteria of the phylum Bacteroidetes were more abundant during PM than CSP (P < 0.05), while protozoa of the genus Eudiplodinium were more abundant during CSP than PM (P < 0.05). Microbial cellular FA profiles differed between treatments. Bacteria and protozoa from cows grazing CSP contained more n-3 FA (P < 0.001) and vaccenic acid (P < 0.01), but lower proportions of branched-chain FA (P < 0.05). Microbial FA correlated with microbial taxa and levels of vaccenic acid, rumenic acid, and α-linolenic acid in milk. In conclusion, grazing regime can potentially be used to alter microbial communities shifting the FA profile of microbial cells, and subsequently, alter the milk FA profile.

Classical ecology provides principles for construction and function of biological communities, but to what extent these apply to the animal-associated microbiota is just beginning to be assessed. Here, we investigated the influence of several well-known ecological principles on animal-associated microbiota by characterizing gut microbial specimens from bilaterally symmetrical animals (Bilateria) ranging from flies to whales. A rigorously vetted sample set containing 265 specimens from 64 species was assembled. Bacterial lineages were characterized by 16S rRNA gene sequencing. Previously published samples were also compared, allowing analysis of over 1,098 samples in total. A restricted number of bacterial phyla was found to account for the great majority of gut colonists. Gut microbial composition was associated with host phylogeny and diet. We identified numerous gut bacterial 16S rRNA gene sequences that diverged deeply from previously studied taxa, identifying opportunities to discover new bacterial types. The number of bacterial lineages per gut sample was positively associated with animal mass, paralleling known species-area relationships from island biogeography and implicating body size as a determinant of community stability and niche complexity. Samples from larger animals harbored greater numbers of anaerobic communities, specifying a mechanism for generating more-complex microbial environments. Predictions for species/abundance relationships from models of neutral colonization did not match the data set, pointing to alternative mechanisms such as selection of specific colonists by environmental niche. Taken together, the data suggest that niche complexity increases with gut size and that niche selection forces dominate gut community construction., IMPORTANCE The intestinal microbiome of animals is essential for health, contributing to digestion of foods, proper immune development, inhibition of pathogen colonization, and catabolism of xenobiotic compounds. How these communities assemble and persist is just beginning to be investigated. Here we interrogated a set of gut samples from a wide range of animals to investigate the roles of selection and random processes in microbial community construction. We show that the numbers of bacterial species increased with the weight of host organisms, paralleling findings from studies of island biogeography. Communities in larger organisms tended to be more anaerobic, suggesting one mechanism for niche diversification. Nonselective processes enable specific predictions for community structure, but our samples did not match the predictions of the neutral model. Thus, these findings highlight the importance of niche selection in community construction and suggest mechanisms of niche diversification.

Cuba has some of the most well-protected coastal ecosystems in the Caribbean Sea, with strong marine policies and legislation, including a system of marine protected areas intended to cover 25% of its insular shelf. The "crown jewel" of the system, Jardines de la Reina National Park, has near pristine levels of apex predators and well-preserved coral reefs. Yet overfishing, illegal fishing, land-based pollution, and global changes, including increased bleaching events and more intense hurricanes, are widespread stressors and major threats to marine ecosystems. Limited resources have hindered Cuba's ability to address these threats. Despite having numerous shared species and resources with the United States, the political division between the two governments has resulted in limited transfer of scientific information. At the end of 2014, the Obama and Castro administrations announced that they would begin improving relations after an approximately 50- yr gap that followed the US embargo of 1962, presenting an opportunity for more scientific exchange and collaboration in environmental management. This special issue of the Bulletin of Marine Science celebrates Cuban marine science and conservation efforts, while recognizing that improved relations and increased tourism and trade could put some natural areas at risk. Joint research shows promise that Cuba, the US, and other countries can work together on regional conservation efforts.

In coupled human and natural systems ecosystem services form the link between ecosystem function and what humans want and need from their surroundings. Interactions between natural and human components are bidirectional and define the dynamics of the total system. Here we describe the MIMES, an analytical framework designed to assess the dynamics associated with ecosystem service function and human activities. MIMES integrate diverse types of knowledge and elucidate how benefits from ecosystem services are gained and lost. In MIMES, users formalize how materials are transformed between natural, human, built, and social capitals. This information is synthesized within a systems model to forecast ecosystem services and human-use dynamics under alternative scenarios. The MIMES requires that multiple ecological and human dynamics be specified, and that outputs may be understood through different temporal and spatial lenses to assess the effects of different actions in the short and long term and at different spatial scales. Here we describe how MIMES methodologies were developed in association with three case studies: a global application, a watershed model, and a marine application. We discuss the advantages and disadvantage of the MIMES approach and compare it to other broadly used ecosystem service assessment tools.

Baleen and sperm whales, known collectively as the great whales, include the largest animals in the history of life on Earth. With high metabolic demands and large populations, whales probably had a strong influence on marine ecosystems before the advent of industrial whaling: as consumers of fish and invertebrates; as prey to other large-bodied predators; as reservoirs of and vertical and horizontal vectors for nutrients; and as detrital sources of energy and habitat in the deep sea. The decline in great whale numbers, estimated to be at least 66% and perhaps as high as 90%, has likely altered the structure and function of the oceans, but recovery is possible and in many cases is already underway. Future changes in the structure and function of the world's oceans can be expected with the restoration of great whale populations.

The study presents the first systematic review of the existing literature on Arctic ES. Applying the Search, Appraisal, Synthesis and Analysis (SALSA) and snowballing methods and three selection criteria, 33 publications were sourced, including peer-reviewed articles, policy papers and scientific reports, and their content synthesised using the thematic analysis method. Five key themes were identified: (1) general discussion of Arctic ES, (2) Arctic social-ecological systems, (3) ES valuation, (4) ES synergies and/or trade-offs, and (5) integrating the ES perspective into management. The meta-synthesis of the literature reveals that the ES concept is increasingly being applied in the Arctic context in all five themes, but there remain large knowledge gaps concerning mapping, assessment, economic valuation, analysis of synergies, trade-offs, and underlying mechanisms, and the social effects of ES changes. Even though ES are discussed in most publications as being relevant for policy, there are few practical examples of its direct application to management. The study concludes that more primary studies of Arctic ES are needed on all of the main themes as well as governance initiatives to move Arctic ES research from theory to practice.

Passed in 1972, the Marine Mammal Protection Act has two fundamental objectives: to maintain U.S. marine mammal stocks at their optimum sustainable populations and to uphold their ecological role in the ocean. The current status of many marine mammal populations is considerably better than in 1972. Take reduction plans have been largely successful in reducing direct fisheries bycatch, although they have not been prepared for all at-risk stocks, and fisheries continue to place marine mammals as risk. Information on population trends is unknown for most (71%) stocks; more stocks with known trends are improving than declining: 19% increasing, 5% stable, and 5% decreasing. Challenges remain, however, and the act has generally been ineffective in treating indirect impacts, such as noise, disease, and prey depletion. Existing conservation measures have not protected large whales from fisheries interactions or ship strikes in the northwestern Atlantic. Despite these limitations, marine mammals within the U.S. Exclusive Economic Zone appear to be faring better than those outside, with fewer species in at-risk categories and more of least concern.

In a single well-mixed population, equally abundant neutral alleles are equally likely to persist. However, in spatially complex populations structured by an asymmetric dispersal mechanism, such as a coastal population where larvae are predominantly moved downstream by currents, the eventual frequency of neutral haplotypes will depend on their initial spatial location. In our study of the progression of two spatially separate, genetically distinct introductions of the European green crab ( Carcinus maenas ) along the coast of eastern North America, we captured this process in action. We documented the shift of the genetic cline in this species over 8 y, and here we detail how the upstream haplotypes are beginning to dominate the system. This quantification of an evolving genetic boundary in a coastal system demonstrates that novel genetic alleles or haplotypes that arise or are introduced into upstream retention zones (regions whose export of larvae is not balanced by import from elsewhere) will increase in frequency in the entire system. This phenomenon should be widespread when there is asymmetrical dispersal, in the oceans or on land, suggesting that the upstream edge of a species’ range can influence genetic diversity throughout its distribution. Efforts to protect the upstream edge of an asymmetrically dispersing species’ range are vital to conserving genetic diversity in the species.

Aim To determine timing, source and vector for the recent introduction of the European green crab, Carcinus maenas (Linnaeus, 1758), to Newfoundland using multiple lines of evidence. Location Founding populations in Placentia Bay, Newfoundland, Canada and potential source populations in the north-west Atlantic (NWA) and Europe. Methods We analysed mitochondrial and microsatellite genetic data from European and NWA populations sampled during 1999‐2002 to determine probable source locations and vectors for the Placentia Bay introduction discovered in 2007. We also analysed Placentia Bay demographic data and shipping records to look for congruent patterns with genetic analyses. Results Demographic data and surveys suggested that C. maenas populations are established and were in Placentia Bay for several years (c. 2002) prior to discovery. Genetic data corroboratively suggested central/western Scotian Shelf populations (e.g., Halifax) as the likely source area for the anthropogenic introduction. These Scotian Shelf populations were within an admixture zone made up of genotypes from both the earlier (early 1800s) and later (late 1900s) introductions of the crab to the NWA from Europe. Placentia Bay also exhibited this mixed ancestry. Probable introduction vectors included vessel traffic and shipping, especially vessels carrying ballast water. Main conclusions Carcinus maenas overcame considerable natural barriers (i.e., coastal and ocean currents) via anthropogenic transport to become established and abundant in Newfoundland. Our study thus demonstrates how non-native populations can be important secondary sources of introduction especially when aided by human transport. Inference of source populations was possible owing to the existence of an admixture zone in central/western Nova Scotia made up of southern and northern genotypes corresponding with the crab’s two historical

Changes in the type and prevalence of human diseases have occurred during shifts in human social organization, for example, from hunting and gathering to agriculture and with urbanization during the Industrial Revolution. The recent emergence and reemergence of infectious diseases appears to be driven by globalization and ecological disruption. We propose that habitat destruction and biodiversity loss associated with biotic homogenization can increase the incidence and distribution of infectious diseases affecting humans. The clearest connection between biotic homogenization and infectious disease is the spread of nonindigenous vectors and pathogens. The loss of predators and hosts that dilute pathogen transmission can also increase the incidence of vectorborne illnesses. Other mechanisms include enhanced abiotic conditions for pathogens and vectors and higher host-pathogen encounter rates. Improved understanding of these causal mechanisms can inform decisionmaking on biodiversity conservation as an effective way to protect human health.

There is mounting evidence that reduced genetic diversity in invasive populations is not as commonplace as expected. Recent studies indicate that high propagule vectors, such as ballast water and shellfish transplantations, and multiple introductions contribute to the elimination of founder effects in the majority of successful aquatic invasions. Multiple introductions, in particular, can promote range expansion of introduced populations through both genetic and demographic mechanisms. Closely related to vectors and corridors of introduction, propagule pressure can play an important role in determining the genetic outcome of introduction events. Even low-diversity introductions have numerous means of avoiding the negative impact of diversity loss. The interaction of high propagule vectors and multiple introductions reveal important patterns associated with invasion success and deserve closer scrutiny.

Under the U.S. Environmental Protection Agency's mission to protect human health and the environment, the agency seeks to conduct research on the structure and function of ecosystems and to improve our understanding of the processes that contribute to the sustained health of the nation's ecosystems and the well-being of human populations. Changes in biodiversity can profoundly impact the ability of ecosystems to provide clean water, energy, food, recreation, and other services that contribute to human well-being. In addition, changes in biodiversity can affect the transmission of infectious disease to humans, particularly vectorborne diseases such as malaria and Lyme disease. The Environmental Protection Agency's new initiative supports interdisciplinary research to characterize the mechanisms that link biodiversity and human health and to use this knowledge to develop integrative tools and approaches for quantifying and predicting these rela- tionships. Research on these links can have an important impact on our view of biodiversity and how we manage resources to protect human and ecosystem health.

The past was a world of giants, with abundant whales in the sea and large animals roaming the land. However, that world came to an end following massive late-Quaternary megafauna extinctions on land and widespread population reductions in great whale populations over the past few centuries. These losses are likely to have had important consequences for broad-scale nutrient cycling, because recent literature suggests that large animals disproportionately drive nutrient movement. We estimate that the capacity of animals to move nutrients away from concentration patches has decreased to about 8% of the preextinction value on land and about 5% of historic values in oceans. For phosphorus (P), a key nutrient, upward movement in the ocean by marine mammals is about 23% of its former capacity (previously about 340 million kg of P per year). Movements by seabirds and anadromous fish provide important transfer of nutrients from the sea to land, totalling ∼150 million kg of P per year globally in the past, a transfer that has declined to less than 4% of this value as a result of the decimation of seabird colonies and anadromous fish populations. We propose that in the past, marine mammals, seabirds, anadromous fish, and terrestrial animals likely formed an interlinked system recycling nutrients from the ocean depths to the continental interiors, with marine mammals moving nutrients from the deep sea to surface waters, seabirds and anadromous fish moving nutrients from the ocean to land, and large animals moving nutrients away from hotspots into the continental interior.

Mammals host gut microbiomes of immense physiological consequence, but the determinants of diversity in these communities remain poorly understood. Diet appears to be the dominant factor, but host phylogeny also seems to be an important, if unpredictable, correlate. Here we show that baleen whales, which prey on animals (fish and crustaceans), harbor unique gut microbiomes with surprising parallels in functional capacity and higher level taxonomy to those of terrestrial herbivores. These similarities likely reflect a shared role for fermentative metabolisms despite a shift in primary carbon sources from plant-derived to animal-derived polysaccharides, such as chitin. In contrast, protein catabolism and essential amino acid synthesis pathways in baleen whale microbiomes more closely resemble those of terrestrial carnivores. Our results demonstrate that functional attributes of the microbiome can vary independently even given an animal-derived diet, illustrating how diet and evolutionary history combine to shape microbial diversity in the mammalian gut., Diet is a major factor determining the composition of gut microbiota in mammals, while host evolutionary history seems to play an unclear role. Here, Sanders et al. show that baleen whales, which prey on animals, harbour a unique gut microbiome with similarities to those of terrestrial herbivores.

Most invasion histories include an estimated arrival time, followed by range expansion. Yet, such linear progression may not tell the entire story. The European green crab ( Carcinus maenas ) was first recorded in the US in 1817, followed by an episodic expansion of range to the north. Its population has recently exploded in the Canadian Maritimes. Although it has been suggested that this northern expansion is the result of warming sea temperatures or cold-water adaptation, Canadian populations have higher genetic diversity than southern populations, indicating that multiple introductions have occurred in the Maritimes since the 1980s. These new genetic lineages, probably from the northern end of the green crab's native range in Europe, persist in areas that were once thought to be too cold for the original southern invasion front. It is well established that ballast water can contain a wide array of nonindigenous species. Ballast discharge can also deliver genetic variation on a level comparable to that of native populations. Such gene flow not only increases the likelihood of persistence of invasive species, but it can also rapidly expand the range of long-established nonindigenous species.

Biologists and policymakers are accustomed to managing species in decline, but for the first time in generations they are also encountering recovering populations of ocean predators. Many citizens perceive these species as invaders and conflicts are increasing. It is time to celebrate these hard-earned successes and lift baselines for recovering species.

The Gaia hypothesis, which proposes that Earth's biota and material environment form a self-regulating system, has been influential in conservation biology, but it has not translated into specific guidelines. Proponents of phylogenetics and ecology often claim primacy over the foundations of conservation biology, a debate that has deep roots in philosophy and science. A more recent claim is that conservation efforts should protect evolutionary processes that will allow diversification. Phylogenetics, ecology, and evolution all have legitimate roles in conservation, when viewed in a temporal perspective. Phylogenetic studies identify the bioheritage of past species radiations, ecology preserves the life-support systems for these lineages in the present, and evolutionary processes allow adaptation of these lineages to novel challenges in the future. The concept of temporal domains in conservation (past, present, future) has an appropriate metaphor in the Norse worldview known as the Orlog. In this body of mythology, three sisters tend the tree of life and fend off a dragon gnawing at the roots. The names of these sisters, Urd, Verdandi, and Skuld, translate to Past, Present, and Future. In Viking mythology, the threads of life cannot persist without the cooperation of these sisters. In the science of conservation biology, they represent the handmaidens of Gaia–three scientific disciplines that can succeed only with a spirit of familial cooperation.

The European green crab, Carcinus maenas , has a native distribution that extends from Norway to Mauritania. It has attracted attention because of its recent invasions of Australia, Tasmania, South Africa, Japan and both coasts of North America. To examine the population structure of this global invader in its native range, we analysed a 502-base-pair fragment of the mitochondrial cytochrome c oxidase I (COI) gene from 217 crabs collected in the North Atlantic and 13 specimens from the Mediterranean. A clear genetic break (11% sequence divergence) occurs between the Mediterranean and Atlantic, supporting the species-level status of these two forms. Populations in the Faeroe Islands and Iceland were genetically distinct from continental populations ( F ST = 0.264–0.678), with Iceland represented by a single lineage also found in the Faeroes. This break is consistent with a deep-water barrier to dispersal in green crabs. Although there are relatively high levels of gene flow along the Atlantic coast of Europe, slight population structure was found between the central North Sea and populations to the south. Analysis of variance, multidimensional scaling, and the distribution of private haplotypes support this break, located between Bremerhaven, Germany, and Hoek van Holland. Similar biogeographical and genetic associations for other species, such as benthic algae and freshwater eels, suggest that the marine fauna of Europe may be generally subdivided into the areas of Mediterranean, western Europe and northern Europe.

The Alligator Snapping Turtle, Macrochelys temminckii, is a large, aquatic turtle limited to river systems that drain into the Gulf of Mexico. Previous molecular analyses using both mitochondrial and nuclear DNA suggested that Macrochelys exhibits significant genetic variation across its range that includes three distinct genetic assemblages (western, central, and eastern = Suwannee). However, no taxonomic revision or morphological analyses have been conducted previously. In this study, we test previous hypotheses of distinct geographic assemblages by examining morphology, reanalyzing phylogeographic genetic structure, and estimating divergence dating among lineages in a coalescent framework using Bayesian inference. We reviewed the fossil record and discuss phylogeographic and taxonomic implications of the existence of three distinct evolutionary lineages. We measured cranial (n=145) and post-cranial (n=104) material on field-captured individuals and museum specimens. We analyzed 420 base pairs (bp) of mitochondrial DNA sequence data for 158 Macrochelys. We examined fossil Macrochelys from ca. 15-16 million years ago (Ma) to the present to better assess historical distributions and evaluate named fossil taxa. The morphological and molecular data both indicate significant geographical variation and suggest three species-level breaks among genetic lineages that correspond to previously hypothesized genetic assemblages. The holotype of Macrochelys temminckii is from the western lineage. Therefore, we describe two new species as Macrochelys apalachicolae sp. nov. from the central lineage and Macrochelys suwanniensis sp. nov. from the eastern lineage (Suwannee River drainage). Our estimates of divergence times suggest that the most recent common ancestor (MRCA) of M. temminckii (western) and M. apalachicolae (central) existed 3.2-8.9 Ma during the late Miocene to late Pliocene, whereas M. temminckii-M. apalachicolae and M. suwanniensis last shared a MRCA 5.5-13.4 Ma during the mid-Miocene to early Pliocene. Examination of fossil material revealed that the fossil taxon M. floridana is actually a large Chelydra. Our taxonomic revision of Macrochelys has conservation and management implications in Florida, Georgia, and Alabama.

Biological invasions offer unique opportunities to investigate evolutionary dynamics at the peripheries of expanding populations. Here, we examine genetic patterns associated with admixture between two distinct invasive lineages of the European green crab,Carcinus maenasL., independently introduced to the northwest Atlantic. Previous investigations based on mitochondrial DNA sequences demonstrated that larval dispersal driven by advective currents could explain observed southward displacement of an admixture zone between the two invasions. Comparison of published mitochondrial results with new nuclear data from nine microsatellite loci, however, reveals striking discordance in their introgression patterns. Specifically, introgression of mitochondrial genomes relative to nuclear background suggests that demographic processes such as sex-biased reproductive dynamics and population size imbalances—and not solely larval dispersal—play an important role in driving the evolution of the genetic cline. In particular, the unpredicted introgression of mitochondrial alleles against the direction of mean larval dispersal in the region is consistent with recent models invoking similar demographic processes to explain movements of genes into invading populations. These observations have important implications for understanding historical shifts inC. maenasrange limits, and more generally for inferences of larval dispersal based on genetic data.

We studied the diets of four sympatric carnivores in the flooding savannas of western Venezuela by analysing predator DNA and prey remains in faeces. DNA was isolated and a portion of the cytochrome b gene of the mitochondrial genome amplified and sequenced from 20 of 34 scats. Species were diagnosed by comparing the resulting sequences to reference sequences generated from the blood of puma ( Puma concolor ), jaguar ( Panthera onca ), ocelot ( Leopardus pardalus ) and crab-eating fox ( Cerdocyon thous ). Scat size has previously been used to identify predators, but DNA data show that puma and jaguar scats overlap in size, as do those of puma, ocelot and fox. Prey-content analysis suggests minimal prey partitioning between pumas and jaguars. In field testing this technique for large carnivores, two potential limitations emerged: locating intact faecal samples and recovering DNA sequences from samples obtained in the wet season. Nonetheless, this study illustrates the tremendous potential of DNA faecal studies. The presence of domestic dog ( Canis familiaris ) in one puma scat and of wild pig ( Sus scrofa ), set as bait, in one jaguar sample exemplifies the forensic possibilities of this noninvasive analysis. In addition to defining the dietary habits of similar size sympatric mammals, DNA identifications from faeces allow wildlife managers to detect the presence of endangered taxa and manage prey for their conservation.