European Wolf Research Articles

New records of Common Wolf Snake Lycodon aulicus (Linnaeus, 1758) (Serpentes: Colubridae) from Uttar Pradesh (India), with distribution of other Indian species

Present study deals with the new records of Lycodon aulicus (Linnaeus, 1758), the Common Wolf Snake, belonging to family Colubridae, from Shikohabad (Firozabad district) and Ghaziabad proper(Ghaziabad dist.), Uttar Pradesh (India) with its systematic account, distribution, habitat, food & feeding, breeding, behaviour, threats and distribution of other Indian species.

The First Report on the Ecology and Distribution of the Wolf Population in Cilento, Vallo di Diano and Alburni National Park

The Apennine wolf (Canis lupus italicus, Altobello, 1921) is currently experiencing a period of great population change. Any information that helps to understand this transformation will be valuable for managing it. Here we provide, for the first time, quantitative data (habitat suitability, segregation, seasonal activity, daily time budget, social structure and sex-ratio) on the population of Italian wolf from the Cilento, Vallo di Diano and Alburni National Park, the largest protected area in Italy, that houses a rising population. Using transects to locate signs and traces, we have identified 224 presence points, useful for elaborating the ecological suitability map for the wolf, in and around the Park. The suitable area expands up to 1042.65 km2, with elevation being the strongest predictive variable affecting the species. The model predicts two main suitable patches (Alburni Mountains and Cervati/Motola Mountains), and at least seven remote areas, differently linked to each other by ecological corridors. Camera-trapping information was collected in the two suitable patches (Alburni and Cervati/Motola) for the wolf and revealed some characteristics of this population. The highest number of wolves was recorded in May and December, and during the night, depending on the reproductive behavior and dynamic of dispersion. Single individuals and couples (at least 3 recorded) are observed more frequently than groups (maximum of 3 groups that varied from three to eight individuals). The sex-ratio in the population, inferred by camera-trapping, showed a balanced population, with males found to be group leader in 91% of the cases. Furthermore, genetic analysis revealed that the males were in charge of marking the territory in 86% of cases. Our data increases the knowledge of the wolf population from Cilento, which seemed to have stopped at the 1990s, until now. Our contribution could be helpful in defining a wolf management strategy in the National Park, as well as in the other regions of the Apennine mountains and Alps, where the wolf is expanding, aiming also at coexistence with local human communities.

Genomes of Pleistocene Siberian Wolves Uncover Multiple Extinct Wolf Lineages

SummaryExtant Canis lupus genetic diversity can be grouped into three phylogenetically distinct clades: Eurasian and American wolves and domestic dogs.1 Genetic studies have suggested these groups trace their origins to a wolf population that expanded during the last glacial maximum (LGM)1, 2, 3 and replaced local wolf populations.4 Moreover, ancient genomes from the Yana basin and the Taimyr peninsula provided evidence of at least one extinct wolf lineage that dwelled in Siberia during the Pleistocene.35 Previous studies have suggested that Pleistocene Siberian canids can be classified into two groups based on cranial morphology. Wolves in the first group are most similar to present-day populations, although those in the second group possess intermediate features between dogs and wolves.67 However, whether this morphological classification represents distinct genetic groups remains unknown. To investigate this question and the relationships between Pleistocene canids, present-day wolves, and dogs, we resequenced the genomes of four Pleistocene canids from Northeast Siberia dated between >50 and 14 ka old, including samples from the two morphological categories. We found these specimens cluster with the two previously sequenced Pleistocene wolves, which are genetically more similar to Eurasian wolves. Our results show that, though the four specimens represent extinct wolf lineages, they do not form a monophyletic group. Instead, each Pleistocene Siberian canid branched off the lineage that gave rise to present-day wolves and dogs. Finally, our results suggest the two previously described morphological groups could represent independent lineages similarly related to present-day wolves and dogs.

Survival of an Extinct in the Wild skink from Christmas Island is reduced by an invasive centipede: implications for future reintroductions

The blue-tailed skink (Cryptoblepharus egeriae) is endemic to Christmas Island but underwent rapid population declines in the 1990s and 2000s and was listed as Extinct in the Wild in 2017. As invasive giant centipedes (Scolependra subspinipes) were implicated as a cause of a failed reintroduction of captive bred skinks into a fenced enclosure, we undertook a mesocosm experiment to investigate if skink survival and body condition was negatively affected by the presence and density of S. subspinipes. In addition, we used DNA barcoding to determine if wild centipedes consume other reptile species on Christmas Island. In the mesocosm experiments, survival of skinks was reduced by 30% and 44% at low and high centipede densities respectively over 12 weeks, and skink body condition also declined significantly over this period. DNA barcoding confirmed that skinks that were lost during the mesocosm experiment had been consumed by centipedes. Further, we detected DNA of two invasive reptiles (the common wolf snake Lycodon capucinus and the Asian House gecko Hemidactylus frenatus) in the stomachs of wild-caught centipedes, suggesting that centipedes are a generalist predator of reptiles in this island ecosystem. Based on these results, we recommend that attempts to reintroduce C. egeriae to Christmas Island should include the control of centipedes to increase the likelihood of success.

Using social network methodological approach to better understand human–wildlife interactions

Human-wildlife interactions (HWI) are present in areas where wild animals and humans compete for limited space, sometimes resulting in potentially harmful conflicts on both sides. The upper Prahova Valley within the central Carpathian range of Romania represents an area where interactions between humans and wildlife can still be found, but potentially conflicting due to the presence of both large intact natural habitats and increasing human pressure over the environment. In our study, we hypothesize that an adequate understanding of the HWI problem involves analyses on landscape pattern, natural or human induced triggering factors, and local stakeholders’ perception of the phenomenon including the measures they consider suitable for optimizing their interactions with wild animals. Therefore, the goal of our paper was to analyse the characteristics of the HWI phenomenon in the upper Prahova Valley, based on exploring the local stakeholders’ perspective. The study methodology consists of three steps: (i) applying 450 questionnaires to local stakeholders in order to extract HWI data; (ii) detecting the interconnection between various types of HWI and the perception of local people, using statistical and network approaches; and (iii) develop a set of recommendations which are applicable at both, local and regional decisional level in order to decrease the negative impact of HWI, enhance wildlife conservation strategies and promote a sustainable interactions with humans and mitigate potential conflicts that occur between humans and wildlife. The results indicate that the brown bear, wild boar and red fox were constantly increasing in HWI after 1990, while interactions with Eurasian wolf, stone marten, European polecat, roe deer and mountain viper were usually scarcer. The brown bear and wild boar were the prior species involved in conflict interactions with humans, such as the destruction of fences, orchards, or gardens. The bear was the only wildlife responsible for non-fatal human attacks. Locals consider the lack of wildlife food supply by the forest staff and the deficient forest management practices after 1990 to be the main triggering factors of these negative HWI. They perceive that the interactions with these animals pose a high risk to human security. Our results stand as a strong argument for a complex management system concerning the HWI phenomenon which adapts upper-level policies and governance decisions to both local stakeholder’s needs and wildlife management objectives to be achieved in order to attain a favorable conservation status.

Morphological and Immunohistochemical Description of a Splenic Haemangioma in a Captive European Wolf (Canis lupus lupus) and a Review of the Current Literature.

Neoplastic diseases are rarely described in wild carnivores; only a few reports have been published on this topic. Here, we describe the histological and immunohistochemical features of a haemangioma in the spleen of a grey wolf (Canis lupus lupus) and we compare the results with the dog (Canis lupus familiaris). Additionally, we list the different publications found in the literature with neoplastic lesions in wolves. Our results show similar immunohistochemical features to dogs, in which neoplastic cells express Vimentin, von Willebrand factor, alpha smooth muscle actin antibody, vascular endothelial growth factor C and low vascular endothelial growth factor receptor 3. Toluidine blue special stain shows moderated increased numbers of mast cells infiltrating the tumor, a feature observed in benign vascular tumors in domestic dogs, but not in the malignant counterparts. To our knowledge, this is the first article describing the gross, histological and immunohistochemical features of a splenic haemangioma in a wolf.

Patterns of Livestock Depredation and Large Carnivore Conservation Implications in the Indian Trans-Himalaya

Livestock is one of the major sources of livelihood for the agro-pastoral communities in central and south Asia. Livestock depredation by large carnivores is a wide-ranging issue that leads to economic losses and a deviance from co-existence. We investigated the grass root factors causing livestock depredation in Kargil, Ladakh and tested the findings of diet analysis in validating reported livestock depredation. Globally vulnerable snow leopard (Panthera uncia) and more common wolf (Canis lupus) were the two main wild predators. A total of 1113 heads of livestock were reportedly killed by wolf (43.6%) followed by unknown predators (31.4%) and snow leopard (21.5%) in the study site from 2009 to 2012, which comes to 2.8% annual livestock losses. Scat analysis also revealed a significant amount of livestock in the diet of snow leopard (47%) and wolf (51%). Poor livestock husbandry practices and traditional livestock corrals were found to be the major drivers contributing in the livestock depredation. Based on the research findings, we worked with the local communities to sensitize them about wildlife conservation and extended limited support for predator proof livestock corrals at a small scale. Eventually it helped in reducing conflict level and conserving the globally threatened carnivores. We conclude that a participatory approach has been successful to generate an example in reducing large carnivore-human conflict in the west Himalaya.

Genomic evidence for the Old divergence of Southern European wolf populations.

The grey wolf (Canis lupus) is one of the most widely distributed mammals in which a variety of distinct populations have been described. However, given their currently fragmented distribution and recent history of human-induced population decline, little is known about the events that led to their differentiation. Based on the analysis of whole canid genomes, we examined the divergence times between Southern European wolf populations and their ancient demographic history. We found that all present-day Eurasian wolves share a common ancestor ca 36 000 years ago, supporting the hypothesis that all extant wolves derive from a single population that subsequently expanded after the Last Glacial Maximum. We also estimated that the currently isolated European populations of the Iberian Peninsula, Italy and the Dinarics-Balkans diverged very closely in time, ca 10 500 years ago, and maintained negligible gene flow ever since. This indicates that the current genetic and morphological distinctiveness of Iberian and Italian wolves can be attributed to their isolation dating back to the end of the Pleistocene, predating the recent human-induced extinction of wolves in Central Europe by several millennia.

European agreements for nature conservation need to explicitly address wolf-dog hybridisation

Hybridisation between wolves and dogs is increasingly reported in Europe. Nonetheless, no systematic survey has ever been attempted at the continental scale. We made the first assessment of wolf-dog hybridisation (WDH) occurrence in Europe and analysed how the phenomenon is addressed by international legislation and managed at the country level. We found that WDH is reported in all nine extant European wolf populations, and in 21 out of 26 countries for which we received information. The two main international legal instruments (i.e., the Habitats Directive and the Bern Convention) do not explicitly mention the threat posed by hybridisation but do provide guidance promoting control of free-ranging wolf-dog hybrids. However, we recorded poor compliance with such recommendations in most European countries, and a lack of coordination in addressing WDH among countries sharing the same wolf population. Alarmingly, we revealed a lack of well-designed and implemented country-wide genetic surveys to detect and monitor hybridisation, both relevant pre-requisites to effectively implement WDH management. By recommending criteria for an operative definition of “hybrid”, we also suggest improvements to enhance WDH-related policy at the European scale.

Molecular survey of tick-borne pathogens reveals a high prevalence and low genetic variability of Hepatozoon canis in free-ranging grey wolves (Canis lupus) in Germany

Wild carnivores are important hosts for ixodid ticks and presumed reservoirs for several tick-borne pathogens (TBPs) of medical and veterinary importance. However, little is known about the role that the European grey wolf (Canis lupus) plays in the enzootic cycle of TBPs. The recent recolonization of Central European lowland, including some regions in Germany, by the grey wolf, opened up an excellent opportunity for studying the impact of the wolf population on pathogen diversity and transmission dynamics. Therefore, in the present study, we investigated spleen samples collected from 276 grey wolves in 11 federal states in Germany for common TBPs by molecular methods. In total, 127 grey wolves (46.0 %) were found to be positive for Hepatozoon canis. Only two genetic variants of this protozoan parasite (herein designated as G1 and G2) were found to circulate among the grey wolves, which can be potentially shared between populations of domestic and other wild carnivores in the country. Two grey wolves were positive for Anaplasma phagocytophilum (0.7 %), and both were co-infected with H. canis G1 genotype. The presence of other pathogens could not be confirmed by PCR and sequencing. This study represents the first one reporting H. canis in a grey wolf population worldwide, and it provides highly relevant information, which may contribute to a better understanding of the epidemiology of TBPs and the pathogen transmission dynamics among the reintroduced population of grey wolves and other carnivores.

Global Phylogeographic and Admixture Patterns in Grey Wolves and Genetic Legacy of An Ancient Siberian Lineage

The evolutionary relationships between extinct and extant lineages provide important insight into species’ response to environmental change. The grey wolf is among the few Holarctic large carnivores that survived the Late Pleistocene megafaunal extinctions, responding to that period’s profound environmental changes with loss of distinct lineages and phylogeographic shifts, and undergoing domestication. We reconstructed global genome-wide phylogeographic patterns in modern wolves, including previously underrepresented Siberian wolves, and assessed their evolutionary relationships with a previously genotyped wolf from Taimyr, Siberia, dated at 35 Kya. The inferred phylogeographic structure was affected by admixture with dogs, coyotes and golden jackals, stressing the importance of accounting for this process in phylogeographic studies. The Taimyr lineage was distinct from modern Siberian wolves and constituted a sister lineage of modern Eurasian wolves and domestic dogs, with an ambiguous position relative to North American wolves. We detected gene flow from the Taimyr lineage to Arctic dog breeds, but population clustering methods indicated closer similarity of the Taimyr wolf to modern wolves than dogs, implying complex post-divergence relationships among these lineages. Our study shows that introgression from ecologically diverse con-specific and con-generic populations was common in wolves’ evolutionary history, and could have facilitated their adaptation to environmental change.

Comparison of minidogfiler and "ASCH" STR multiplex systems for preliminary estimation of variability within wolf´s like dog breeds

This study was undertaken to estimate basic population parameters and compare resolution capabilities of two chosen STR panels (Mini-DogFiler, MDF; “ASCH”). Wolf´s like dog breeds, namely Czechoslovakian wolfdog (n = 55), Saarloos wolfdog (n = 22), and samples of the Eurasian wolf (n = 21) were selected for their close genetic relationship. Also, German Shepherd (n = 26) breed was included as a donor of dog genome for the Czechoslovakian wolfdog.Overall 228 alleles were detected using 20 STR markers (MDF 11 and “ASCH” 9 loci). Number of alleles ranged from 3 to 23 per locus, with median 11 alleles per locus for MDF and 10 for “ASCH”. Both panels showed similar level of variability in the means of number of alleles per locus (k) and observed heterozygostity (HO) as there were not found statistically significant differences (Mann-Whithey U-test; p = 0.85 for k, p = 0.88 for HO). A group of wolves showed the highest variability unlike Saarloos wolfdog with very low variability within all measured parameters, although such differences were statistically significant only for k parameter of MDF panel (Kruskal-Wallis ANOVA; p = 0.0003) and no other groups were different. Both microsatellite panels were able correctly distinguish 3 dog breeds and wolfs as was verified by STRUCTURE programme and several potential hybrids were identified. Moreover, this pilot analysis amenable creation of allelic ladders for MDF and “ASCH” panels and thus ensure consistency and reliability of future study with extended number of samples.

Detection of selected pathogens in Apennine wolf (Canis lupus italicus) by a non-invasive GPS-based telemetry sampling of two packs from Majella National Park, Italy.

In this study, a multi-pathogens survey was conducted to verify the sanitary status of two Italian wolf packs of Majella National Park. Twenty fecal samples (10/pack) were collected using a sampling protocol, based on the combining data from radio-collared wolves with geographic information system (GIS) analysis, allowing to mark off the home range of packs and to recover group-specific and high-quality specimens. Virological screening against the most prevalent canine viruses (protoparvovirus, distemper virus, adenoviruses, and coronaviruses) was carried out by molecular methods, while parasites were detected by means of copromicroscopic and molecular analysis. Canine parvovirus type 2b (CPV-2b) is the most prevalent virus in both packs (7/20), followed by canine adenovirus type 2 (CAdV-2), while no sequences of canine distemper virus and coronaviruses were detected. The sequence analysis of the viruses demonstrated the domestic origin of the infection, highlighting the importance of vaccination of local dogs in order to reduce the risk of exposure of wildlife to these pathogens. Fourteen samples resulted positive for parasites. Capillaria aerophila (sin. Eucoleus aerophilus), Ancylostoma/Uncinaria, Trichuris vulpis eggs, Sarcocystis spp., Cystoisospora canis, and Angiostrongylus vasorum larvae were identified. Echinococcus granulosus sensu stricto (ovine genotype G1) and Giardia duodenalis(canid-specific Assemblage C) were also characterized, providing insights into the wolves’ diet and their effects on environmental contamination. The sampling protocol applied in this study, based on a multidisciplinary approach, represents an innovative tool for the survey of Apennine wolf, able to integrate sanitary data with the ecological and demographic features of this population.Electronic supplementary materialThe online version of this article (10.1007/s10344-019-1326-y) contains supplementary material, which is available to authorized users.

Dogs, but Not Wolves, Lose Their Sensitivity Toward Novelty With Age.

Selection of behavioral traits holds a prominent role in the domestication of animals, and domesticated species are generally assumed to express reduced fear and reactivity toward novel stimuli compared to their ancestral species. However, very few studies have explicitly tested this proposed link between domestication and reduced fear responses. Of the limited number of studies experimentally addressing the alterations of fear during domestication, the majority has been done on canids. These studies on foxes, wolves, and dogs suggest that decreased expression of fear in domesticated animals is linked to a domestication-driven delay in the first onset of fearful behavior during early ontogeny. Thus, wolves are expected to express exaggerated fearfulness earlier during ontogeny compared to dogs. However, while adult dogs are less fearful toward novelty than adult wolves and wolf-dog hybrids, consensus is lacking on when differences in fear expression arise in wolves and dogs. Here we present the first extended examination of fear development in hand-raised dogs and European gray wolves, using repeated novel object tests from 6 to 26 weeks of age. Contrary to expectations, we found no evidence in support of an increase in fearfulness in wolves with age or a delayed onset of fear response in dogs compared to wolves. Instead, we found that dogs strongly reduced their fear response in the period between 6 and 26 weeks of age, resulting in a significant species difference in fear expression toward novelty from the age of 18 weeks. Critically, as wolves did not differ in their fear response toward novelty over time, the detected species difference was caused solely by a progressive reduced fear response in dogs. Our results thereby suggest that species differences in fear of novelty between wolves and dogs are not caused by a domestication-driven shift in the first onset of fear response. Instead, we suggest that a loss of sensitivity toward novelty with age in dogs causes the difference in fear expression toward novelty in wolves and dogs.

De Novo Mutation Rate Estimation in Wolves of Known Pedigree.

Knowledge of mutation rates is crucial for calibrating population genetics models of demographic history in units of years. However, mutation rates remain challenging to estimate because of the need to identify extremely rare events. We estimated the nuclear mutation rate in wolves by identifying de novo mutations in a pedigree of seven wolves. Putative de novo mutations were discovered by whole-genome sequencing and were verified by Sanger sequencing of parents and offspring. Using stringent filters and an estimate of the false negative rate in the remaining observable genome, we obtain an estimate of ∼4.5 × 10−9 per base pair per generation and provide conservative bounds between 2.6 × 10−9 and 7.1 × 10−9. Although our estimate is consistent with recent mutation rate estimates from ancient DNA (4.0 × 10−9 and 3.0–4.5 × 10−9), it suggests a wider possible range. We also examined the consequences of our rate and the accompanying interval for dating several critical events in canid demographic history. For example, applying our full range of rates to coalescent models of dog and wolf demographic history implies a wide set of possible divergence times between the ancestral populations of dogs and extant Eurasian wolves (16,000–64,000 years ago) although our point estimate indicates a date between 25,000 and 33,000 years ago. Aside from one study in mice, ours provides the only direct mammalian mutation rate outside of primates and is likely to be vital to future investigations of mutation rate evolution.

Biodiversity lost: The phylogenetic relationships of a complete mitochondrial DNA genome sequenced from the extinct wolf population of Sicily

Using next-generation sequencing, we obtained for the first time a complete mitochondrial DNA genome from a museum specimen of the extinct wolf (Canis lupus) population of the island of Sicily (Italy). Phylogenetic analyses indicated that this genome, which was aligned with a number of historical and extant wolf and dog mitogenomes sampled worldwide, was closely related to an Italian wolf mtDNA genome (the observed proportion of nucleotide sites at which the two sequences are different was p = 0.0012), five to seven times shorter than divergence among Sicilian and any other known wolf mtDNA genomes (p range = 0.0050 – 0.0070). Sicilian and Italian mitogenomes joined a basal clade belonging to the mtDNA haplogroup-2 of ancient western European wolf populations (Pilot et al., 2010). Bayesian calibration of divergence times indicated that this clade coalesced at MRCA = 13.400 years (with 95% HPD = 4000 – 21.230 years). These findings suggest that wolves probably colonized Sicily from southern Italy towards the end of the last Pleistocene glacial maximum when the Strait of Messina was almost totally dry. Additional mtDNA and genomic data will further clarify the origin and population dynamics before the extinction of wolves in Sicily.

Feeding Enrichment in a Captive Pack of European Wolves (Canis Lupus Lupus): Assessing the Effects on Welfare and on a Zoo's Recreational, Educational and Conservational Role.

Simple SummaryFeeding enrichment is widely used to improve the welfare of zoo animals, but it may also affect zoo visitors’ experience and perception of the animals. The objective of this study was to assess the effects of a naturalistic and a non-naturalistic feeding enrichment program, on both wolf behaviour and visitors’ interest in the exhibit. A questionnaire was administered to visitors with the aim of assessing whether our feeding enrichment programs might affect their perception of captive wolf welfare as well as their attitude towards wolf conservation issues. Our findings suggest that, although wolves seemed to benefit from enrichment, their behavioural responses were highly variable among individuals. Visitors’ interest in the exhibit and perception of captive wolf welfare improved by observing the wolves interacting with food, especially when novel feeding objects were provided. Finally, their attitude towards wolf conservation issues did not change in relation to enrichment, but improved when they observed the wolves performing feeding-related behaviours. These findings may help zoos implement enrichment programs that are effective for enhancing their wolves’ welfare as well as their recreational and educational role.This study investigated the effects of two feeding enrichment programs on the behaviour of a captive pack of European wolves (Canis lupus lupus) and their correlation with both zoo visitors’ interest towards the exhibit and their overall perception of the species. Behavioural data (exploration, stereotypies, social interactions, activity/inactivity rates) were collected on four male wolves during four two-week long phases: initial control, hidden food, novel object, final control. Three observation sessions were performed daily: before, during and after feeding. Number of visitors and their permanence in front of the exhibit were recorded. After watching the wolves, visitors were asked to fill out a brief questionnaire in order to investigate their perception of captive wolf welfare, as well as their attitude towards wolf conservation issues. Despite the high inter-individual variability in their behavioural response, all wolves seemed to benefit from feeding enrichment. With regard to visitors, interest in the exhibit increased when enrichment was provided. Visitors’ perception of the level of welfare of wolves improved if they attended a feeding session, especially during the novel object phase. Visitors’ attitude towards wolf conservation issues also improved during feeding sessions, regardless of enrichment provision.

The Sicilian Wolf: Genetic Identity of a Recently Extinct Insular Population.

Historically, many local grey wolf (Canis lupus) populations have undergone substantial reductions in size or become extinct. Among these, the wolf population once living in Sicily, the largest island in the Mediterranean Sea, was completely eradicated by human activity in the early decades of the 20th century. To gain a better understanding of the genetic identity of the Sicilian wolf, we used techniques for the study of ancient DNA to analyze the mitochondrial (mt) variability of six specimens stored in Italian museums. We were able to amplify a diagnostic mtDNA fragment of the control region (CR) in four of the samples. Two of the samples shared the same haplotype, differing by two substitutions from the currently most diffused Italian wolf haplotype (W14) and one substitution from the only other Italian haplotype (W16). The third sample showed a previously unreported wolf-like haplotype, and the fourth a haplotype commonly found in dogs. All of the wolf haplotypes analyzed in this study belonged to the mitochondrial haplogroup that includes haplotypes detected in all the known European Pleistocene wolves and in several modern southern European populations. Unfortunately, this endemic island population, which exhibited unique mtDNA variability, was definitively lost before it was possible to understand its taxonomic uniqueness and conservational value.

Bony labyrinth shape differs distinctively between modern wolves and dogs

Additional reliable anatomical markers are needed for differentiating archaeological wolves and dogs, to support clarifying the origin(s) of dogs. Candidate structures should have good potential to survive various taphonomic conditions. The petrous bone is one potential differentiating structure, and could be further useful when aDNA cannot be extracted otherwise. The petrous bone houses the bony labyrinth (semicircular canals, vestibule, and cochlea). Across a number of taxa, its intricate shape has been shown to carry indicator taxonomic information, supporting clear distinctions between and among mammalian groups. In this report, we explore the three-dimensional shape of the bony labyrinth of wolves and dogs, using micro-computed tomography and 3D geometric morphometrics. We examined 20 modern Eurasian wolves and 20 modern mesaticephalic dogs with comparable skull lengths. We show that dogs have on average a significantly smaller bony labyrinth than wolves. In shape space, wolves and dogs form significantly different, non-overlapping clusters with dogs having a larger relative size of the lateral semicircular canal, smaller relative size of the vertical canals and oval window, and shorter relative cochlea streamline length, with a more antero-ventrally tilted modiolus. These shape differences are not related to allometric effects. Results of this study warrant examination of preserved archaeological and paleo-ontological petrous bones from the oldest possible dogs and isopatric wolves.

Old wild wolves: ancient DNA survey unveils population dynamics in Late Pleistocene and Holocene Italian remains

BackgroundThe contemporary Italian wolf (Canis lupus italicus) represents a case of morphological and genetic uniqueness. Today, Italian wolves are also the only documented population to fall exclusively within the mitochondrial haplogroup 2, which was the most diffused across Eurasian and North American wolves during the Late Pleistocene. However, the dynamics leading to such distinctiveness are still debated.MethodsIn order to shed light on the ancient genetic variability of this wolf population and on the origin of its current diversity, we collected 19 Late Pleistocene-Holocene samples from northern Italy, which we analyzed at a short portion of the hypervariable region 1 of the mitochondrial DNA, highly informative for wolf and dog phylogenetic analyses.ResultsFour out of the six detected haplotypes matched the ones found in ancient wolves from northern Europe and Beringia, or in modern European and Chinese wolves, and appeared closely related to the two haplotypes currently found in Italian wolves. The haplotype of two Late Pleistocene samples matched with primitive and contemporary dog sequences from the canine mitochondrial clade A. All these haplotypes belonged to haplogroup 2. The only exception was a Holocene sample dated 3,250 years ago, affiliated to haplogroup 1.DiscussionIn this study we describe the genetic variability of the most ancient wolf specimens from Italy analyzed so far, providing a preliminary overview of the genetic make-up of the population that inhabited this area from the last glacial maximum to the Middle Age period. Our results endorsed that the genetic diversity carried by the Pleistocene wolves here analyzed showed a strong continuity with other northern Eurasian wolf specimens from the same chronological period. Contrarily, the Holocene samples showed a greater similarity only with modern sequences from Europe and Asia, and the occurrence of an haplogroup 1 haplotype allowed to date back previous finding about its presence in this area. Moreover, the unexpected discovery of a 24,700-year-old sample carrying a haplotype that, from the fragment here obtained, falls within the canine clade A, could represent the oldest evidence in Europe of such dog-rich clade. All these findings suggest complex population dynamics that deserve to be further investigated based on mitochondrial or whole genome sequencing.