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1.
Globally, long‐term research is critical to monitor the responses of tropical species to climate and land cover change at the range scale. Citizen science surveys can reveal the long‐term persistence of poorly known nomadic tropical birds occupying fragmented forest patches. We applied dynamic occupancy models to 13 years (2002–2014) of citizen science‐driven presence/absence data on Cape parrot (Poicephalus robustus), a food nomadic bird endemic to South Africa. We modeled its underlying range dynamics as a function of resource distribution, and change in climate and land cover through the estimation of colonization and extinction patterns. The range occupancy of Cape parrot changed little over time (ψ = 0.75–0.83) because extinction was balanced by recolonization. Yet, there was considerable regional variability in occupancy and detection probability increased over the years. Colonizations increased with warmer temperature and area of orchards, thus explaining their range shifts southeastwards in recent years. Although colonizations were higher in the presence of nests and yellowwood trees (Afrocarpus and Podocarpus spp.), the extinctions in small forest patches (≤227 ha) and during low precipitation (≤41 mm) are attributed to resource constraints and unsuitable climatic conditions. Loss of indigenous forest cover and artificial lake/water bodies increased extinction probabilities of Cape parrot. The land use matrix (fruit farms, gardens, and cultivations) surrounding forest patches provides alternative food sources, thereby facilitating spatiotemporal colonization and extinction in the human‐modified matrix. Our models show that Cape parrots are vulnerable to extreme climatic conditions such as drought which is predicted to increase under climate change. Therefore, management of optimum sized high‐quality forest patches is essential for long‐term survival of Cape parrot populations. Our novel application of dynamic occupancy models to long‐term citizen science monitoring data unfolds the complex relationships between the environmental dynamics and range fluctuations of this food nomadic species.  相似文献   

2.
Animal host–microbe interactions are a relevant concern for wildlife conservation, particularly regarding generalist pathogens, where domestic host species can play a role in the transmission of infectious agents, such as viruses, to wild animals. Knowledge on viral circulation in wild host species is still scarce and can be improved by the recent advent of modern molecular approaches. We aimed to characterize the fecal virome and identify viruses of potential conservation relevance of diarrheic free‐ranging wolves and sympatric domestic dogs from Central Portugal, where a small and threatened wolf population persists in a highly anthropogenically modified landscape. Using viral metagenomics, we screened diarrheic stools collected from wolves (n = 8), feral dogs (n = 4), and pet dogs (n = 6), all collected within wolf range. We detected novel highly divergent viruses as well as known viral pathogens with established effects on population dynamics, including canine distemper virus, a novel bocavirus, and canine minute virus. Furthermore, we performed a 4‐year survey for the six wolf packs comprising this endangered wolf population, screening 93 fecal samples from 36 genetically identified wolves for canine distemper virus and the novel bocavirus, previously identified using our metagenomics approach. Our novel approach using metagenomics for viral screening in noninvasive samples of wolves and dogs has profound implications on the knowledge of both virology and wildlife diseases, establishing a complementary tool to traditional screening methods for the conservation of threatened species.  相似文献   

3.
Hippobosca longipennis (Diptera: Hippoboscidae), the dog fly or dog louse fly, is an obligate blood‐feeding ectoparasite of wild and domestic carnivores in Africa and the Middle East. Outside its typically known geographic range, H. longipennis has been reported occasionally on mainly domestic dogs in Asia and southern Europe, and infrequently in other areas (central Europe and the U.S.A.). This paper presents the first report of H. longipennis in Romania and the second record of Lipoptena fortisetosa (Diptera: Hippoboscidae), a potentially invasive species. Hippobosca longipennis was found on domestic dogs in two regions of the country (northern Romania in Maramures and southwestern Romania in Dobrogea) and on two road‐killed wildcats in Maramures. Lipoptena fortisetosa was found on domestic dogs in Maramures. In both species identification was based on morphology and confirmed by barcoding of the cytochrome c oxidase subunit 1 gene. It is not clear for how long H. longipennis has been present in central Europe, nor if it was introduced (via the movement of domestic dogs or import of exotic carnivores) or present historically (Holocene remnants). This paper discusses the possible origins of H. longipennis in central Europe as its current distribution in the area is sparse and patchy.  相似文献   

4.
5.
Over time, populations of species can expand, contract, fragment and become isolated, creating subpopulations that must adapt to local conditions. Understanding how species maintain variation after divergence as well as adapt to these changes in the face of gene flow is of great interest, especially as the current climate crisis has caused range shifts and frequent migrations for many species. Here, we characterize how a mycophageous fly species, Drosophila innubila, came to inhabit and adapt to its current range which includes mountain forests in south‐western USA separated by large expanses of desert. Using population genomic data from more than 300 wild‐caught individuals, we examine four populations to determine their population history in these mountain forests, looking for signatures of local adaptation. In this first extensive study, establishing D. innubila as a key genomic "Sky Island" model, we find D. innubila spread northwards during the previous glaciation period (30–100 KYA) and have recently expanded even further (0.2–2 KYA). D. innubila shows little evidence of population structure, consistent with a recent establishment and genetic variation maintained since before geographic stratification. We also find some signatures of recent selective sweeps in chorion proteins and population differentiation in antifungal immune genes suggesting differences in the environments to which flies are adapting. However, we find little support for long‐term recurrent selection in these genes. In contrast, we find evidence of long‐term recurrent positive selection in immune pathways such as the Toll signalling system and the Toll‐regulated antimicrobial peptides.  相似文献   

6.
The late Pleistocene was a time of environmental change, culminating in an extinction event. Few fossil localities record a temporal series of carnivore fossil populations from this interesting interval as well as Rancho La Brea (RLB). We analysed mandibles of Smilodon fatalis from RLB using 2‐D geometric morphometrics to examine whether, and how, mandibular shape changes through time. Smilodon fatalis shows mandibular evolution with oscillations between a small, ancestral‐type morph in pits 77 (≈37 Kybp) and 2051 (≈26 Kybp), a larger, more derived morph in pits 91 (≈28 Kybp) and 61‐67 (≈13.6 Kybp), and an intermediate morph from pit 13 (≈17.7 Kybp). These oscillations end in pit 61‐67, with greatest body size, and are estimated to have its widest gape and lowest bite force. Additionally, variation is lowest in pit 61‐67, which was deposited concurrent with the Bølling–Allerød warming event, which may have important implications for the timing or conditions during the extinction event. Contra to a temporal Bergmann's rule, such rapid warming events appear to be correlated with larger, derived, morphologies whereas static, cooler, climates correlate with gracile, ancestral morphologies.  相似文献   

7.
The taxonomy of African black rhinoceros (Diceros bicornis) remains unresolved. Maintaining levels of genetic diversity and species rescue by reintroduction and restocking requires its resolution. We compared the sequences of the mitochondrial DNA (mtDNA) control region for a total of 101 D. bicornis from three subspecies: D. b. minor, D. b. michaeli and D. b. bicornis. A single unique haplotype was found within the 65 D. b. minor samples from KwaZulu‐Natal (KZN) Province, South Africa, 55 of which came from Hluhluwe‐iMfolozi Game Park (HiP) and Mkuzi Game Reserve (MGR) source populations. However, six different haplotypes were represented in eleven D. b. minor samples from Zimbabwe. Similarly, published autosomal microsatellite data indicate low levels of diversity within the KZN D. b. minor populations. The low levels of mtDNA diversity within the KZN metapopulation point to the possible need for genetic supplementation. However, there is a need to determine whether the low levels of genetic variation within KZN D. b. minor are a result of the recent bottleneck or whether KZN historically always had low diversity.  相似文献   

8.
Defining the geographic origins of free‐living aquatic microorganisms can be problematic because many such organisms have ubiquitous distributions, and proving absence from a region is practically impossible. Geographic origins become important if microorganisms have invasive characteristics. The freshwater diatom Didymosphenia geminata is a potentially ubiquitous microorganism for which the recent global expansion of nuisance proliferations has been attributed to environmental change. The changes may include declines in dissolved reactive phosphorus (DRP) to low levels (e.g., <2 mg/m3) and increases in dissolved inorganic nitrogen (DIN) to >10 mg/m3 because both these nutrient conditions are associated with nuisance proliferations of D. geminata. Proliferations of D. geminata have been observed in South Island, New Zealand, since 2004. We aimed to address the ubiquity hypothesis for D. geminata in New Zealand using historical river water nutrient data and new molecular analyses. We used 15 years of data at 77 river sites to assess whether trends in DRP or DIN prior to the spread of D. geminata were consistent with a transition from a rare, undetected, species to a nuisance species. We used new sequences of chloroplast regions to examine the genetic similarity of D. geminata populations from New Zealand and six overseas locations. We found no evidence for declines in DRP concentrations since 1989 that could explain the spread of proliferations since 2004. At some affected sites, lowest DRP occurred before 2004. Trends in DIN also did not indicate enhanced suitability for D. geminata. Lack of diversity in the chloroplast intergenic regions of New Zealand populations and populations from western North America is consistent with recent dispersal to New Zealand. Our analyses did not support the proposal that D. geminata was historically present in New Zealand rivers. These results provide further evidence countering proposals of general ubiquity in freshwater diatoms and indicate that, as assumed in 2004, D. geminata is a recent arrival in New Zealand.  相似文献   

9.
The Pleistocene to Holocene transition was accompanied by a worldwide extinction event affecting numerous mammalian species. Several species such as the woolly mammoth and the giant deer survived this extinction wave, only to go extinct a few thousand years later during the Holocene. Another example for such a Holocene extinction is the Don‐hare, Lepus tanaiticus, which inhabited the Russian plains during the late glacial. After being slowly replaced by the extant mountain hare (Lepus timidus), it eventually went extinct during the middle Holocene. Here, we report the phylogenetic relationship of L. tanaiticus and L. timidus based on a 339‐basepair (bp) fragment of the mitochondrial D‐loop. Phylogenetic tree‐ and network reconstructions do not support L. tanaiticus and L. timidus being different species. Rather, we suggest that the two taxa represent different morphotypes of a single species and the extinction of ‘L. tanaiticus’ represents the disappearance of a local morphotype rather than the extinction of a species.  相似文献   

10.
Abundant isolated specimens of microconchid tubes have been extracted from a microbialite deposit near the Permian–Triassic boundary (PTB) in the Dajiang section, southern Guizhou Province, South China. They are assignable to Microconchus aff. utahensis, M. aff. aberrans and Helicoconchus aff. elongatus, all of which possess micro‐lamellar tube walls. Quantitative analysis of bulk samples indicates that most microconchids occur in the upper part of the PTB microbialite deposit and show substrate selectivity for bioclastic grainstone–packstones. In contrast, very few microconchids were found in the rocks bearing well‐developed microbialite structures. Both stratigraphical and substrate preferences indicate proliferation of microconchids coincided with an ebb of microbialite development. Microconchids therefore only proliferated in local niches in which microbial activities were not very active within the PTB microbialite ecosystem. The presence of abundant microconchids further strengthens the impression that PTB microbialite metazoans are much more diverse than previously thought. The end‐Permian mass extinction is calibrated to the base of microbialite deposit in South China. Thus, abundant microbialite metazoans, such as ostracods, lingulid brachiopods, microgastropods and microconchids, together with the considerable, temporarily surviving faunas reported from non‐microbialite PTB sections in South China, indicate that metazoans diversified immediately after the first episode of the end‐Permian mass extinction, supporting the scenario that marine ecosystems underwent episodic collapses during the devastating biocrisis over the Permian–Triassic transition.  相似文献   

11.
Despite substantial interest in coevolution's role in diversification, examples of coevolution contributing to speciation have been elusive. Here, we build upon past studies that have shown both coevolution between South Hills crossbills and lodgepole pine (Pinus contorta), and high levels of reproductive isolation between South Hills crossbills and other ecotypes in the North American red crossbill (Loxia curvirostra) complex. We used genotyping by sequencing to generate population genomic data and applied phylogenetic and population genetic analyses to characterize the genetic structure within and among nine of the ecotypes. Although genome‐wide divergence was slight between ecotypes (FST = 0.011–0.035), we found evidence of relative genetic differentiation (as measured by FST) between and genetic cohesiveness within many of them. As expected for nomadic and opportunistic breeders, we detected no evidence of isolation by distance. The one sedentary ecotype, the South Hills crossbill, was genetically most distinct because of elevated divergence at a small number of loci rather than pronounced overall genome‐wide divergence. These findings suggest that mechanisms related to recent local coevolution between South Hills crossbills and lodgepole pine (e.g. strong resource‐based density dependence limiting gene flow) have been associated with genome divergence in the face of gene flow. Our results further characterize a striking example of coevolution driving speciation within perhaps as little as 6000 years.  相似文献   

12.
The parasitic phaeophycean endophyte Herpodiscus durvillaeae (Lindauer) G. R. South has previously only been recorded from New Zealand, in association with a single host species, Durvillaea antarctica (Chamisso) Hariot (southern bull‐kelp). Here we use DNA sequence data from plastid and nuclear markers (chloroplast rbcL, ribosomal LSU, and a nuclear pseudogene copy of COI) to test for the presence of H. durvillaeae beyond the New Zealand region, and on host species other than D. antarctica. Analyses of samples from the Falkland Islands confirm the first record of H. durvillaeae from the Atlantic Ocean. We report that Falkland Islands H. durvillaeae are genetically indistinguishable from samples of this species from New Zealand's sub‐Antarctic Campbell Island, suggesting recent dispersal of the parasite across the Pacific Ocean, presumably by rafting with its buoyant macroalgal host. We also here record Hdurvillaeae from New Zealand endemics Durvillaea poha Fraser et al. and D. willana Lindauer.  相似文献   

13.
Binary communication systems that involve sex‐specific signaling and sex‐specific signal perception play a key role in sexual selection and in the evolution of sexually dimorphic traits. The driving forces and genetic changes underlying such traits can be investigated in systems where sex‐specific signaling and perception have emerged recently and show evidence of potential coevolution. A promising model is found in Drosophila prolongata, which exhibits a species‐specific increase in the number of male chemosensory bristles. We show that this transition coincides with recent evolutionary changes in cuticular hydrocarbon (CHC) profiles. Long‐chain CHCs that are sexually monomorphic in the closest relatives of D. prolongata (D. rhopaloa, D. carrolli, D. kurseongensis, and D. fuyamai) are strongly male‐biased in this species. We also identify an intraspecific female‐limited polymorphism, where some females have male‐like CHC profiles. Both the origin of sexually dimorphic CHC profiles and the female‐limited polymorphism in D. prolongata involve changes in the relative amounts of three mono‐alkene homologs, 9‐tricosene, 9‐pentacosene, and 9‐heptacosene, all of which share a common biosynthetic origin and point to a potentially simple genetic change underlying these traits. Our results suggest that pheromone synthesis may have coevolved with chemosensory perception and open the way for reconstructing the origin of sexual dimorphism in this communication system.  相似文献   

14.
Emerging evidence shows that interleukin (IL)‐10 gene polymorphisms can regulate its expression level and thus influence person's susceptibility to preeclampsia. However, various published results were inconsistent. To explore the association between maternal IL‐10 gene polymorphisms and preeclampsia, we performed a meta‐analysis based upon 11 individual studies here. Our meta‐analysis results indicated that IL‐10 ‐819C/T (C versus T, OR = 1.28, 95% CI = 1.08–1.50, P = 0.003) and ‐592C/A (C versus A, OR = 1.28, 95% CI = 1.03–1.59, P = 0.03) polymorphisms were associated with preeclampsia. Although there was no overall association between ‐1082A/G polymorphism and preeclampsia (G versus A, OR = 0.93, 95% CI = 0.77–1.13, P = 0.49), such association existed among Asian (G versus A, OR = 1.29, 95% CI = 1.04–1.60, P = 0.02) and South American (G versus A, OR = 0.72, 95% CI = 0.54–0.94, P = 0.02) populations in the subgroup analysis stratified by continents.  相似文献   

15.
16.
Temperature during a particular period prior to spring leaf‐out, the temperature‐relevant period (TRP), is a strong determinant of the leaf‐out date in temperate‐zone trees. Climatic warming has substantially advanced leaf‐out dates in temperate biomes worldwide, but its effect on the beginning and length of the TRP has not yet been explored, despite its direct relevance for phenology modeling. Using 1,551 species–site combinations of long‐term (1951–2016) in situ observations on six tree species (namely, Aesculus hippocastanum, Alnus glutinosa, Betula pendula, Fagus sylvatica, Fraxinus excelsior, and Quercus robur) in central Europe, we found that the advancing leaf‐out was accompanied by a shortening of the TRP. On average across all species and sites, the length of the TRP significantly decreased by 23% (p < .05), from 60 ± 4 days during 1951–1965 to 47 ± 4 days during 2002–2016. Importantly, the average start date of the TRP did not vary significantly over the study period (March 2–5, DOY = 61–64), which could be explained by sufficient chilling over the study period in the regions considered. The advanced leaf‐out date with unchanged beginning of the TRP can be explained by the faster accumulation of the required heat due to climatic warming, which overcompensated for the retarding effect of shortening daylength on bud development. This study shows that climate warming has not yet affected the mean TRP starting date in the study region, implying that phenology modules in global land surface models might be reliable assuming a fixed TRP starting date at least for the temperate central Europe. Field warming experiments do, however, remain necessary to test to what extent the length of TRP will continue to shorten and whether the starting date will remain stable under future climate conditions.  相似文献   

17.
Ongoing rapid climate change is predicted to cause local extinction of plant species in mountain regions. However, some plant species could have persisted during Quaternary climate oscillations without shifting their range, despite the limited evidence from fossils. Here, we tested two candidate mechanisms of persistence by comparing the macrorefugia and microrefugia (MR) hypotheses. We used the rare and endemic Saxifraga florulenta as a model taxon and combined ensembles of species distribution models (SDMs) with a high‐resolution paleoclimatic and topographic dataset to reconstruct its potential current and past distribution since the last glacial maximum. To test the macrorefugia hypothesis, we verified whether the species could have persisted in or shifted to geographic areas defined by its realized niche. We then identified potential MR based on climatic and topographic properties of the landscape and applied refined scenarios of MR dynamics and functions over time. Last, we quantified the number of known occurrences that could be explained by either the macrorefugia or MR model. A consensus of two or three SDM techniques predicted absence between 14–10, 3–4 and 1 ka bp , which did not support the macrorefugia model. In contrast, we showed that S. florulenta could have contracted into MR during periods of absence predicted by the SDMs and later re‐colonized suitable areas according to the macrorefugia model. Assuming a limited and realistic seed dispersal distance for our species, we explained a large number of the current occurrences (61–96%). Additionally, we showed that MR could have facilitated range expansions or shifts of S. florulenta. Finally, we found that the most recent and the most stable MR were the ones closest to current occurrences. Hence, we propose a novel paradigm to explain plant persistence by highlighting the importance of supporting functions of MR when forecasting the fate of plant species under climate change.  相似文献   

18.

Aim

Climatic oscillations have been suggested to promote speciation and changes in species distributions, mostly in connection with the Last Glacial Maximum (LGM). However, the LGM is just the most recent of the 20+ glacial‐interglacial periods that characterise the Quaternary. Here, we investigate the role of climatic changes and geomorphological features in shaping the evolution, distribution and population dynamics of the South American cactus Cereus hildmannianus.

Location

South‐eastern South America.

Methods

We built a large fossil‐calibrated phylogeny for cacti (family Cactaceae), comprising 128 species distributed in all subfamilies, using a Bayesian relaxed clock. We used the results to derive a secondary calibration for a population‐level phylogeny in C. hildmannianus. We amplified two plastid (trnQ‐5′rps16 and psbJ‐petA) and one nuclear marker (PhyC) for 24 populations. We estimated population dynamics, ancestral areas, and species distribution models to infer the clade's evolutionary history in time and space.

Results

Our results show a major population divergence of C. hildmannianus at c. 2.60 Ma, which is strikingly coincident with the transition of the Pliocene–Pleistocene and onset of Quaternary glaciations. This was followed by a complex phylogeographic scenario involving population expansions across ecologically diverse regions.

Main conclusions

Contrary to the dominant research focus on the LGM, our study indicates a major impact of the first Quaternary glaciation on the distribution and population divergence of a South American plant species. Further intraspecific events seem related to successive climatic changes and geomorphology, including the development of the coastal plain and its peculiar diversity. We propose that the first Quaternary glaciation acted as a major evolutionary bottleneck, whereby many warm‐adapted lineages succumbed, while those that survived could diversify and better cope with subsequent climatic oscillations.  相似文献   

19.
Drosophila suzukii (Diptera: Drosophilidae), known commonly as spotted wing drosophila, is a vinegar fly originating from South‐East Asia and a major pest to many soft‐skinned fruits. Due to the species recent arrival in North America in 2008, many fruit varieties are yet untested for susceptibility to infestation. While previous work has focused on Vitis vinifera, this study aimed to determine grape susceptibility of cold hardy varieties based on hybrids of V. labrusca, V. riparia and V. vinifera. Field sampling was conducted in Southern Wisconsin (USA) vineyards to establish adult and larval abundance and determine whether the number of adults caught in traps correlates with fruit infestation. Host susceptibility was further assessed through no‐choice bioassays of both intact and damaged fruits. The field study found D. suzukii adults present in all varieties, low larval abundance and no correlation between adult abundance and larval presence. Peak adult abundance occurred mid‐season between veraison and harvest, while larval infestation rates were highest near harvest. In laboratory no‐choice tests, significantly more eggs, larvae and adults occurred in damaged than undamaged grapes. In damaged grapes, larvae and adult abundance was comparable between varieties and to the highly susceptible control of undamaged raspberry; however, D. suzukii developed significantly faster in raspberry than grapes. Fruit characteristics (°Brix, titratable acidity, pH) in grapes were uncorrelated with D. suzukii performance. Together, these findings suggest that cold hardy grapes are overall resistant to D. suzukii if intact and highly susceptible if damaged.  相似文献   

20.
Proterosuchidae is one of the first clades of Archosauriformes (archosaurs and closely related species) to appear in the fossil record, with the richest sample of the group coming from the Lystrosaurus Assemblage Zone (earliest Triassic) of South Africa. Four nominal proterosuchid species were described from South Africa during the twentieth century (Proterosuchus fergusi, Chasmatosaurus vanhoepeni, Chasmatosaurus alexanderi and Elaphrosuchus rubidgei), but interpretations of their taxonomy have been widely disparate. The most recent taxonomic revision concluded that P. fergusi is the only valid species and that the other nominal species are junior subjective synonyms of this taxon. This proposal was based on the interpretation that anatomical differences between the nominal species could be explained as a result of ontogenetic changes and/or post‐mortem deformation. The recent discoveries of multiple new South African proterosuchid specimens provide an impetus to revisit their taxonomy. Based upon a comprehensive re‐examination of all known specimens, as well as examination of other proterosuchid taxa in collections worldwide, we conclude that the holotype of Proterosuchus fergusi is undiagnostic. As a result, we propose a neotype (RC 846) for the species. ‘Chasmatosaurus vanhoepeni’ and ‘Elaphrosuchus rubidgei’ are considered subjective junior synonyms of P. fergusi. ‘Chasmatosaurusalexanderi is considered a valid species, for which we propose the new combination P. alexanderi comb. nov. A third species, P. goweri sp. nov., is erected on the basis of a single specimen (NMQR 880). All three species recognized here are taxonomically distinct from a previously described archosauriform maxilla from the lower Lystrosaurus AZ. As a result, we recognize a minimum of four archosauriform species following the Permo‐Triassic mass extinction in South Africa. Our results suggest a greater species richness of earliest Triassic archosauriforms than previously appreciated, but that archosauriform morphological disparity remained low and did not expand until the late Early Triassic – early Mid‐Triassic.  相似文献   

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