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Island populations have long been important for understanding the dynamics and mechanisms of evolution in natural systems. While genetic drift is often strong on islands due to founder events and population bottlenecks, the strength of selection can also be strong enough to counteract the effects of drift. Here, we used several analyses to identify the roles of genetic drift and selection on genetic differentiation and diversity of Canada lynx (Lynx canadensis) across eastern Canada, including the islands of Cape Breton and Newfoundland. Specifically, we assessed whether we could identify a genetic component to the observed morphological differentiation that has been reported across insular and mainland lynx. We used a dinucleotide repeat within the promoter region of a functional gene that has been linked to mammalian body size, insulin‐like growth factor‐1 (IGF‐1). We found high genetic differentiation at neutral molecular markers but convergence of allele frequencies at the IGF‐1 locus. Thus, we showed that while genetic drift has influenced the observed genetic structure of lynx at neutral molecular markers, natural selection has also played a role in the observed patterns of genetic diversity at the IGF‐1 locus of insular lynx.

Elusive wildlife are challenging to study, manage, or conserve, as the difficulty of obtaining specimens or conducting direct observations leads to major data deficiencies. Specimens of opportunity, such as salvaged carcasses or museum specimens, are a valuable source of fundamental biological and ecological information on data-deficient, elusive species, increasing knowledge of biodiversity, habitat and range, and population structure. Stable isotope analysis is a powerful indirect tool that can be used to infer foraging behavior and habitat use retrospectively from archived specimens. Beaked whales are a speciose group of cetaceans that are challenging to study in situ, and although Sowerby's beaked whale (Mesoplodon bidens) was discovered >200 years ago, little is known about its biology. We measured δ13C and δ15N stable isotope composition in bone, muscle, and skin tissue from 102 Sowerby's beaked whale specimens of opportunity collected throughout the North Atlantic Ocean to infer movement ecology and spatial population structure. Median δ13C and δ15N values in Sowerby's beaked whale bone, muscle, and skin tissues significantly differed between whales sampled from the east and west North Atlantic Ocean. Quadratic discriminant analysis that simultaneously considered δ13C and δ15N values correctly assigned >85% of the specimens to their collection region for all tissue types. These findings demonstrate Sowerby's beaked whale exhibits both short- and long-term site fidelity to the region from which the specimens were collected, suggest that this species is composed of two or more populations or exhibits a metapopulation structure, and have implications for conservation and management policy. Stable isotope analysis of specimens of opportunity proved a highly successful means of generating new spatial ecology data for this elusive species and is a method that can be effectively applied to other elusive species.

Ecology of Canis aureus was seasonally studied from 1983 to 1986 in Tijkda area, National Park of Djurdjura (Algeria). This species presents a complex social organization with seasonal rythms. It lives solitarily or in pair or in small groups. This organization is greatly depending on breeding behaviour. Their territorial organization is also very complex. Investigation by radio-tracking permits to consider that the field territories of two individuals are in part overlapping. Space is organized in territories delimited by some marking signals. Identification of territory becomes very important during breeding season.R sume. -L'ecologie du chacal dore a fait 1'objet d'une etude sur pres de 3 ans, pendant toutes les saisons de l'annee, dans la region de Tikjda, dans le Pare National du Djurdjura. L'etude montre que le chacal ne presente pas une organisation de type solitaire simple mais une organisation sociale complexe qui presente des fluctuations selon les saisons de Tannee. Trois types de groupements ont etc releves : solitaire, par couple et en petits groupes. L Observation de comportements lies ä la reproduction montre que cette organisation sociale en depend pour une large part, alors que Palimentation n'influe sur eile que relativement peu.L'organisation territoriale est egalement complexe. Les donnees recueillies avec le suivi de 2 animaux par radiopistage sur le terrain montrent que les 2 domaines vitaux observes se chevauchent en partie et que leur exploitation se fait de fagon non aleatoire. L'espace est organiso en territoires que I'animal delimite en utilisant difforents signaux de marquage : hurlements, urines accompagnees parfois de grattages du sol et amas de crottes. Le territoire prend toute son importance lors de la periode de reproduction.Le chacal dore est Tun des rares mammiferes qui demeurent encore abondants en Algerie. II est largement repandu dans tout le pays, depuis le littoral jusqu'aux limites meridionales. Bien qu'il soit familier et connu de tous, sa biologic n'a jamais pour autant fait Pobjet d'etudes approfondies. Jusqu'a present, seuls des travaux de systematique sont disponibles. Des observations fragmentaires sur sa biologie ont ete signalees par quelques auteurs (Loche 1867 ; Seurat 1930 ; Anonyme Mammalia, t. 54, n° 3, 1990. Brought to you by | University of Queensland -UQ Library Authenticated Download Date | 6/16/15 1:25 PM