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Local adaptation and adaptive radiations are typically associated with phenotypic variation suited to alternative environments. In the marine environment, the nature of relevant ecological or environmental transitions is poorly understood, especially for highly mobile species. Here we compare three genetic lineages in the genus Tursiops (bottlenose dolphins), using linear measurements and geometric morphometric techniques, in the context of environmental variation in the northwest Indian Ocean. Cranial morphology was clearly differentiated comparing Tursiops truncatus and Tursiops aduncus, while a recently discovered genetic lineage, found in the Arabian Sea, was morphologically most similar to T. aduncus from the same region, but distinct for various measures, particularly metrics associated with the lateral dimension of the skull. The extent of divergence between T. truncatus and T. aduncus compared to differences between the T. aduncus lineages is consistent with the recent phylogeny for these species. Therefore, with the corroboration of genetic and morphological inference, we propose two conservation units of T. aduncus be recognized in the region at a sub-specific level so that their conservation can be managed effectively. We consider possible evolutionary mechanisms associated with regional habitat characteristics and the exploitation of distinct prey resources.

35 pages, 3 figures.-- Open access Marine mammals can play important ecological roles in aquatic ecosystems, and their presence can be key to community structure and function. Consequently, marine mammals are often considered indicators of ecosystem health and flagship species. Yet, historical population declines caused by exploitation, and additional current threats, such as climate change, fisheries bycatch, pollution and maritime development, continue to impact many marine mammal species, and at least 25% are classified as threatened (Critically Endangered, Endangered or Vulnerable) on the IUCN Red List. Conversely, some species have experienced population increases/recoveries in recent decades, reflecting management interventions, and are heralded as conservation successes. To continue these successes and reverse the downward trajectories of at-risk species, it is necessary to evaluate the threats faced by marine mammals and the conservation mechanisms available to address them. Additionally, there is a need to identify evidence-based priorities of both research and conservation needs across a range of settings and taxa. To that effect we: (1) outline the key threats to marine mammals and their impacts, identify the associated knowledge gaps and recommend actions needed; (2) discuss the merits and downfalls of established and emerging conservation mechanisms; (3) outline the application of research and monitoring techniques; and (4) highlight particular taxa/populations that are in urgent need of focus S.E.N. acknowledges funding from the Natural Environment Research Council (NE/L002434/1). S.E.N. and B.J.G. also acknowledge support from the European Union (INDICIT; EU grant agreement no. 110661/ 2018/ 794561/ SUB/ENV. C2). E.C. has a doctoral fellowship from the World Wildlife Foundation - Education for Nature. M.I.D.C. was supported by the UK Department for Business and Industrial Strategy (BEIS; project number OESEA-16-78). D.J.F.R. was supported by National Capability funding from the UK Natural Environment Research Council (NERC) to the Sea Mammal Research Unit (SMRU) (grant no. SMRU1001). A.B.O. acknowledges funding from the Office of Naval Research (award no. N000141613017). D.M.P. was supported by the Whale Habitat Professorship Endowment Fund, Marine Mammal Institute, Oregon State University. K.A.S. was supported by a Royal Society of New Zealand Te Aparangi Rutherford Discovery Fellowship

Here we consider the role of depth as a driver of evolution in a genus of deep-sea fishes. We provide a phylogeny for the genus Coryphaenoides (Gadiformes: Macrouridae) that represents the breadth of habitat use and distributions for these species. In our consensus phylogeny species found at abyssal depths (> 4000 m) form a well-supported lineage, which interestingly also includes two non-abyssal species, C. striaturus and C. murrayi, diverging from the basal node of that lineage. Biogeographic analyses suggest the genus may have originated in the Southern and Pacific Oceans where contemporary species diversity is highest. The abyssal lineage seems to have arisen secondarily and likely originated in the Southern/Pacific Oceans but diversification of this lineage occurred in the Northern Atlantic Ocean. All abyssal species are found in the North Atlantic with the exception of C. yaquinae in the North Pacific and C. filicauda in the Southern Oceans. Abyssal species tend to have broad depth ranges and wide distributions, indicating that the stability of the deep oceans and the ability to live across wide depths may promote population connectivity and facilitate large ranges. We also confirm that morphologically defined subgenera do not agree with our phylogeny and that the Giant grenadier (formally Albatrossia pectoralis) belongs to Coryphaenoides, indicating that a taxonomic revision of the genus is needed. We discuss the implications of our findings for understanding the radiation and diversification of this genus, and the likely role of adaptation to the abyss.

Ecosystem function and resilience is determined by the interactions and independent contributions of individual species. Apex predators play a disproportionately determinant role through their influence and dependence on the dynamics of prey species. Their demographic fluctuations are thus likely to reflect changes in their respective ecological communities and habitat. Here, we investigate the historical population dynamics of the killer whale based on draft nuclear genome data for the Northern Hemisphere and mtDNA data worldwide. We infer a relatively stable population size throughout most of the Pleistocene, followed by an order of magnitude decline and bottleneck during the Weichselian glacial period. Global mtDNA data indicate that while most populations declined, at least one population retained diversity in a stable, productive ecosystem off southern Africa. We conclude that environmental changes during the last glacial period promoted the decline of a top ocean predator, that these events contributed to the pattern of diversity among extant populations, and that the relatively high diversity of a population currently in productive, stable habitat off South Africa suggests a role for ocean productivity in the widespread decline.

Barbuda and Antigua's national animal is the fallow deer, Dama dama dama, a species native to the eastern Mediterranean that has been transported around the world by people during the last 8,000 years. The timing and circumstances by which fallow deer came to be established on Barbuda are currently uncertain but, by examining documentary, osteological and genetic evidence, this paper will consider the validity of existing theories. It will review the dynamics of human-Dama relationships from the 1500s AD to the present day and consider how the meaning attached to this species has changed through time: from a symbol of colonial authority and dominance, to a 'walking larder' after the slave emancipation of 1834, and now an important part of the island's economy and cultural heritage that requires careful management.

Tese de Doutoramento, Biologia, 1 de junho de 2015, Universidade dos Açores. This PhD thesis is focusing on the ecology of a medium sized and poorly studied oceanic dolphin species: The Risso’s dolphin (Grampus griseus). […]. In this study, we present for the first time a model for the social structure of Risso’s dolphin (Grampus griseus Cuvier 1812). Over the period 2004-2006, 1028 Risso’s dolphins were identified at Pico Island, Azores. Individuals sighted on 10 or more occasions were included in analysis of social structure (n = 183). High resighting rates indicate strong site-fidelity of at least part of the population. We found that individuals form stable long-term bonds, organised in pairs, or in clusters of 3-12 individuals. Social structure is stratified based on age and sex classes, with strong associations between adult males and adult females. We suggest that clusters form the basic units of Risso’s dolphin society. Thirteen pods consisting solely of adults, likely males, and 3 pods consisting of mother-calf pairs were identified. Males are organised in stable, long-term associations of varying size that occur throughout the complete range of behavioural states observed. For females, associations can be of similar strength, but the time-scale may vary depending on the presence of nursing calves. As subadults, associations also occur (pair-formation), but are less stable than those observed for adults. We propose a new model for Risso’s dolphin societies known as a stratified social organisation, which differs from the fission-fusion and matrilineal society models. […]. This research was fundamentally supported by the Nova Atlantis Foundation and a Ph.D. grant from Fundo Regional para a Ciência (FRC ref. M3.1.2/F/014/2009). Additional funds and logistic support were provided by CIRN and the European Regional Development Fund (ERDF) through the COMPETE - Operational Competitiveness Programme and national funds through FCT – Foundation for Science and Technology, under the project "PEst-C/MAR/LA0015/2013".