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1.
We made a quantitative analysis of the responses of urban and rural residents in Sweden to arguments supporting and opposing
conservation of large carnivores. The most important arguments in favour of conservation were: “I want them [the large carnivores] to exist in Sweden, even if I will never see any of them”, “Sweden should share the responsibility of conserving the large
carnivores” and “We owe it [conservation of large carnivores] to future generations”. We found only small differences between rural and urban residents. For arguments opposing conservation,
the difference between rural and urban areas was slightly greater. The most important arguments opposing conservation of large
carnivores were: “They may have serious negative impact on livestock farming”, “They may have serious negative impact on reindeer
husbandry” and “May inflict suffering on injured livestock”. We conclude that there seems to be less support for direct use
values such as hunting, ecotourism or just experiencing large carnivores, this may imply that the minimum viable population
size can be used as a long-term management goal for large carnivore populations, possibly with an exception for bears. We
also conclude that a separate conservation or management plan is needed for each species, since the conflicts with human interests
vary greatly between the different carnivore species. 相似文献
2.
Molecular genetic assays can contribute to conservation of aquatic taxa by assessing evolutionary and taxonomic distinctiveness,
levels of genetic variation within and between populations, and the degree of introgression with introduced taxa. The Athabasca
River drainage of␣western Alberta, Canada is one of only three (and the largest) drainages flowing east of the continental
divide that contain native populations of rainbow trout (Salmonidae: Oncorhynchus mykiss). The “Athabasca” rainbow trout has been considered a preglacial relict worthy of special conservation measures. In addition,
the native range of Athabasca rainbow trout has seen many instances of introductions of non-native populations since the beginning
of the 20th century. We assayed rainbow trout from the Athabasca River drainage, from hatchery populations, and from representative
populations in adjacent regions (N = 49 localities) for variation at 10 microsatelite loci to assess the level of evolutionary distinctiveness of Athabasca rainbow
trout, and to assess the levels of introgression with non-native hatchery fish. We found that native Athabasca rainbow trout
did not form a distinctive genetic assemblage and that the greatest amount of allele frequency variation was attributable
to contemporary drainage systems (29.3%) rather than by a Athabasca/non-Athabasca distinction (12.6%). We found that 78% of
all fish were confidently assigned to a “wild” rather than a “hatchery” genetic grouping and that most of the inferred introgression
with hatchery fish was restricted to a few localities (N = 6). Our results suggest that: (i)␣Athabasca River rainbow trout are likely postglacial immigrants from adjacent populations
of the Fraser River, and (ii) that there is no evidence of widespread introgression of hatchery alleles into native Athabasca
River drainage rainbow trout. 相似文献
3.
F. Casas F. Mougeot I. Sánchez-Barbudo J. A. Dávila J. Vi?uela 《Biological invasions》2012,14(2):295-305
Hybridization is a widespread phenomenon, which plays crucial roles in the speciation of living beings. However, unnatural
mixing of historically isolated taxa due to human-related activities has increased in recent decades, favouring levels of
hybridization and introgression that can have important implications for conservation. The wild red-legged partridge (Alectoris rufa, Phasianidae) populations have recently declined and the releases of farm-reared partridges have become a widespread management
strategy. The native range of the red-legged is limited to the south-west of Europe (from Italy to Portugal). This species
does not breed in sympatry with the chukar partridge (A. chukar), whose range is Eurasian (from Turkey to China). However, red-legged partridges have often been hybridized with chukar partridges
to increase the productivity of farmed birds, and game releases may have spread hybrid birds into the wild. In this study,
we investigated the fitness (survival and breeding) differences between hybrid and “pure” red-legged partridges in a wild
population located in central Spain. Incubation probability was similar in hybrids and “pure” partridges. Hybrid females laid
larger clutches than “pure” ones, but hatching success did not differ between hybrid and “pure” partridges. Hybrid birds had
lower survival rate than “pure” ones, mainly because of higher predation rates. Our results show that, despite lower survival,
hybrid partridges breed in natural populations, so this could increase extinction risk of wild pure partridge populations,
through releases of farmed hybrid birds. The consequences of continued releases could be of vital importance for the long
term conservation of wild red-legged partridges. 相似文献
4.
Joseph D. DiBattista 《Conservation Genetics》2008,9(1):141-156
Genetic variation is considered critical for allowing natural populations to adapt to their changing environment, and yet
the effects of human disturbance on genetic variation in the wild are poorly understood. Different types of human disturbances
may genetically impact natural populations in a predictable manner and so the aim of this study was to provide an overview
of these changes using a quantitative literature review approach. I examined both allozyme and microsatellite estimates of
genetic variation from peer-reviewed journals, using the mean number of alleles per locus and expected heterozygosity as standardized
metrics. Populations within each study were categorized according to the type of human disturbance experienced (“hunting/harvest”,
“habitat fragmentation”, or “pollution”), and taxon-specific, as well as time- and context-dependent disturbance effects were
considered. I found that human disturbances are associated with weak, but consistent changes in neutral genetic variation
within natural populations. The direction of change was dependent on the type of human disturbance experienced, with some
forms of anthropogenic challenges consistently decreasing genetic variation from background patterns (e.g., habitat fragmentation),
whereas others had no effect (e.g., hunting/harvest) or even slightly increased genetic variation (e.g., pollution). These
same measures appeared sensitive to both the time of origin and duration of the disturbance as well. This suggests that the
presence or absence, strength, type, as well as the spatial and temporal scale of human disturbance experienced may warrant
careful consideration when conservation management plans are formulated for natural populations, with particular attention
paid to the effects of habitat fragmentation. 相似文献
5.
Seventy-five years ago, the geneticist Richard Goldschmidt hypothesized that single mutations affecting development could
result in major phenotypic changes in a single generation to produce unique organisms within animal populations that he called
“hopeful monsters”. Three decades ago, Sarah P. Gibbs proposed that photosynthetic unicellular micro-organisms like euglenoids
and dinoflagellates are the products of a process now called “secondary endosymbiosis” (i.e., the evolution of a chloroplast
surrounded by three or four membranes resulting from the incorporation of a eukaryotic alga by a eukaryotic heterotrophic
host cell). In this article, we explore the evidence for Goldschmidt’s “hopeful monster” concept and expand the scope of this
theory to include the macroevolutionary emergence of organisms like Euglena and Chlorarachnion from secondary endosymbiotic events. We argue that a Neo-Goldschmidtian perspective leads to the conclusion that cell chimeras
such as euglenids and dinoflagellates, which are important groups of phytoplankton in freshwater and marine ecosystems, should
be interpreted as “successful monsters”. In addition, we argue that Charles Darwin had euglenoids (infusoria) in mind when
he speculated on the “primordial intermediate form”, although his Proto-Euglena-hypothesis for the origin of the last common
ancestor of all forms of life is no longer acceptable. 相似文献
6.
?těpánka ?í?anová Josef Bryja Jean-Fran?ois Cosson Csongor Gedeon Luká? Choleva Michal Ambros Franti?ek Sedlá?ek 《Conservation Genetics》2011,12(4):1115-1129
Habitat fragmentation may influence the genetic make-up and adaptability of endangered populations. To facilitate genetic
monitoring of the endangered European ground squirrel (EGS), we analyzed 382 individuals from 16 populations in Central Europe,
covering almost half of its natural range. We tested how fragmentation affects the genetic architecture of presumably selectively
neutral (12 microsatellites) and non-neutral (the major histocompatibility class II DRB gene) loci. Spatial genetic analyses
defined two groups of populations, “western” and “eastern”, with a significantly higher level of habitat fragmentation in
the former group. The highly fragmented western populations had significantly lower genetic diversity in both types of markers.
Only one allele of the DRB gene predominated in populations of the western group, while four alleles were evenly distributed
across the eastern populations. Coefficient of inbreeding values (F
IS) calculated from microsatellites were significantly higher in the western (0.27–0.79) than in eastern populations (−0.060–0.119).
Inter-population differentiation was very high, but similar in both groups (western F
ST = 0.23, eastern F
ST = 0.25). The test of isolation by distance was significant for the whole dataset, as well as for the two groups analyzed
separately. Comparison of genetic variability and structure on microsatellites and the DRB gene does not provide any evidence
for contemporary selection on MHC genes. We suggest that genetic drift in small bottlenecked and fragmented populations may
overact the role of balancing selection. Based on the resulting risk of inbreeding depression in the western populations,
we support population management by crossbreeding between the western and eastern populations. 相似文献
7.
Karine Louise dos Santos Nivaldo Peroni Raymond Paul Guries Rubens Onofre Nodari 《Economic botany》2009,63(2):204-214
Traditional Knowledge and Management of
Feijoa (Acca sellowiana)
in Southern Brazil. This paper investigates traditional knowledge of the use and management of Acca sellowiana in southern Brazil. Fifty-six informants from three rural communities were assigned to one of four subgroups (“maintainers,”
“managers,” “cultivators,” or “users”) based on their responses regarding management and use of A. sellowiana. Traditional knowledge related to use of this species is widespread among rural residents, but traditional knowledge related
to management is fragmented depending on whether one uses, manages, or cultivates the species. Knowledge held in rural communities
suggests that A. sellowiana could play an expanded role in local economies as well as biodiversity conservation. We suggest that participatory research
could stimulate greater local use as well as on-farm conservation of A. sellowiana. 相似文献
8.
Linda Laikre Lena C. Larsson Anna Palmé Johan Charlier Melanie Josefsson Nils Ryman 《Biodiversity and Conservation》2008,17(4):893-910
Programs for monitoring biological diversity over time are needed to detect changes that can constitute threats to biological
resources. The convention on biological diversity regards effective monitoring as necessary to halt the ongoing erosion of
biological variation, and such programs at the ecosystem and species levels are enforced in several countries. However, at
the level of genetic biodiversity, little has been accomplished, and monitoring programs need to be developed. We define “conservation
genetic monitoring” to imply the systematic, temporal study of genetic variation within particular species/populations with
the aim to detect changes that indicate compromise or loss of such diversity. We also (i) identify basic starting points for
conservation genetic monitoring, (ii) review the availability of such information using Sweden as an example, (iii) suggest
categories of species for pilot monitoring programs, and (iv) identify some scientific and logistic issues that need to be
addressed in the context of conservation genetic monitoring. We suggest that such programs are particularly warranted for
species subject to large scale enhancement and harvest—operations that are known to potentially alter the genetic composition
and reduce the variability of populations. 相似文献
9.
10.
Animals often exhibit accelerated or “compensatory” growth (CG) after periods of environmentally induced growth depression,
raising important questions about how they cope with environmental variability. We tested an underexplored hypothesis regarding
the evolutionary consequences of CG; namely, that natural populations differ in CG responses. Common-garden experiments were
used to compare subadult growth following food restriction between groups (control, treatment) of two Atlantic salmon (Salmo salar) populations and their first-generation (F1) hybrids. The populations are found at similar latitudes but characterized by differences in migration distance. We predicted
that long-distance migrants would better maintain growth trajectories following food restriction than short-distance migrants
because they: (1) require larger body sizes to offset energetic costs of migration and (2) face greater time constraints for
growth as they must leave non-breeding areas earlier to return to breeding areas. Long-distance migrants grew faster, achieved
quicker CG (relative to controls), and their overall body morphology was more streamlined (a trait known to improve swimming
efficiency) than slower growing short-distance migrants. F1 hybrids were generally intermediate in “normal” growth, CG, and body morphology. We concluded that CG responses may differ
considerably among populations and that the conditions generating them are likely interconnected with selection on a suite
of other traits. 相似文献
11.
Carroll SP 《Genetica》2007,129(2):193-204
Classical examples indicated rapid evolution to be both rare and largely anthropogenic. As the pace and scale of human disturbance
increase, such evolution is becoming more the norm. Genetically based adaptation may underlie successful biological invasions,
and may likewise characterize responses in natives to invasives. Recent published studies confirm that natives are adapting
morphologically, behaviorally, physiologically and life historically to selection from invasive species. Some of the processes
involved are evident in our studies of recent host shifts to invasive plants by native soapberry bugs in North America and
Australia. On both continents populations have differentiated extensively in fitness traits. Genetic architecture of these
adaptations involves a surprising degree of non-additive variation (epistasis, dominance), a result that in theory may reflect
a history of colonization by a small number of individuals followed by population growth. Such “founder-flush” events may
unleash extraordinary evolutionary potential, and their importance will be clarified as more studies take advantage of the
accidental perturbation experiments that biotic invasions represent. From a conservation standpoint, rapid evolution in natives
will present challenges for ecologically appropriate and sustainable management, but at the same time may enhance the capacity
of the native community to act in the biological control of invasive species. 相似文献
12.
Protein evolution is not a random process. Views which attribute randomness to molecular change, deleterious nature to single-gene
mutations, insufficient geological time, or population size for molecular improvements to occur, or invoke “design creationism”
to account for complexity in molecular structures and biological processes, are unfounded. Scientific evidence suggests that
natural selection tinkers with molecular improvements by retaining adaptive peptide sequence. We used slot-machine probabilities
and ion channels to show biological directionality on molecular change. Because ion channels reside in the lipid bilayer of
cell membranes, their residue location must be in balance with the membrane’s hydrophobic/philic nature; a selective “pore”
for ion passage is located within the hydrophobic region. We contrasted the random generation of DNA sequence for KcsA, a
bacterial two-transmembrane-domain (2TM) potassium channel, from Streptomyces lividans, with an under-selection scenario, the “jackprot,” which predicted much faster evolution than by chance. We wrote a computer
program in JAVA APPLET version 1.0 and designed an online interface, The Jackprot Simulation
, to model a numerical interaction between mutation rate and natural selection during a scenario of polypeptide evolution.
Winning the “jackprot,” or highest-fitness complete-peptide sequence, required cumulative smaller “wins” (rewarded by selection)
at the first, second, and third positions in each of the 161 KcsA codons (“jackdons” that led to “jackacids” that led to the
“jackprot”). The “jackprot” is a didactic tool to demonstrate how mutation rate coupled with natural selection suffices to
explain the evolution of specialized proteins, such as the complex six-transmembrane (6TM) domain potassium, sodium, or calcium
channels. Ancestral DNA sequences coding for 2TM-like proteins underwent nucleotide “edition” and gene duplications to generate
the 6TMs. Ion channels are essential to the physiology of neurons, ganglia, and brains, and were crucial to the evolutionary
advent of consciousness. The Jackprot Simulation illustrates in a computer model that evolution is not and cannot be a random
process as conceived by design creationists. 相似文献
13.
Heat shock proteins HSP70 and GP96: structural insights 总被引:3,自引:0,他引:3
Facciponte JG Wang XY MacDonald IJ Park JE Arnouk H Grimm MJ Li Y Kim H Manjili MH Easton DP Subjeck JR 《Cancer immunology, immunotherapy : CII》2006,55(3):339-346
Several heat shock proteins (HSPs) act as potent adjuvants for eliciting anti-tumor immunity. HSP-based tumor vaccine strategies
have been highly successful in animal models and are undergoing testing in clinical trials. It is generally accepted that
HSPs, functioning as chaperones for tumor antigens, elicit tumor-specific adaptive immune responses. HSPs also appear to induce
innate immune responses in an antigen-independent fashion. Innate responses generated by HSPs may contribute to anti-tumor
immunity. Immunologically active chaperones with anti-tumor activity are referred to as “immunochaperones”. Here, we review
the studies that address the role of structural domains or regions of the immunochaperones HSP70 and GP96 that may be involved
in the induction of adaptive or innate immune responses.
This article forms part of the Symposium in Writing “Thermal stress-related modulation of tumor cell physiology and immune
responses”, edited by Elfriede Noessner. 相似文献
14.
Personality means suites of correlated behavioural traits, also referred to as “behavioural syndromes” or “personality dimensions”.
Across animal taxa similar combinations of traits seem to prevail, which may have proximate foundation in common neuroendocrine
mechanisms. Hitherto, these have been rarely studied in intact social settings. We investigated personalities of greylag goose
males from a free-roaming flock that shows complex social relationships. In connection with our longitudinal study on the
consistency of behavioural and physiological responses to multiple challenges, we asked whether and how single, personality-related
behavioural traits correlate with each other to form personality dimension(s). We tested whether these dimensions were related
to physiological characteristics that previously showed limited plasticity (heart rate (HR), baseline and stress-induced excreted
immuno-reactive corticosterone (BM), and testosterone metabolites levels) and, furthermore, to age, body measures, and dominance
rank. Principal-components analysis based on behavioural variables revealed two factors: 51.1% of variability was explained
by “aggressiveness” and a further 19.1% by “sociability”. “Aggressiveness” comprised correlated measures of aggression, subordinance,
boldness, vigilance, and proximity to the mate. This “aggressiveness” positively correlated with stress-induced BM levels,
the HR increase during aggressive interactions, and with dominance rank, which may suggest proximate and functional contingencies
of this personality dimension. 相似文献
15.
A mathematical model of HIV dynamics in the presence of a rescuing virus with replication deficiency
Recently, an enzyme (Cre recombinase) has been developed by directed evolution that successfully removes the HIV genome from
the nuclear DNA of infected cells. To explore this idea further, we hypothesized that a replication deficient virus (called
“police virus”), added externally, can deliver such a recombinase which excises the integrated HIV DNA from the genome of
infected cells. Such a “police virus” could attack and remove the integrated provirus which is not possible using contemporary
strategies. The hypothesis was tested by developing a mathematical model that describes the dynamics of virus-host cell interaction
and the consequences of introducing the “police virus”. The simulations show that such a therapeutic vector may eradicate
all HIV viruses from the system in the long term. All components of the HIV infection (free virus, latently, and actively
infected cells) can be cleared and the system ends up only with susceptible CD4+ cells. The proposed model may provide new
insights in the dynamical behavior and future alternative treatments of HIV. 相似文献
16.
Biologists studying short-lived organisms have become aware of the need to recognize an explicit temporal extend of a population
over a considerable time. In this article we outline the concept and the realm of populations with explicit spatial and temporary
boundaries. We call such populations “temporally bounded populations”. In the concept, time is of the same importance as space
in terms of a dimension to which a population is restricted. Two parameters not available for populations that are only spatially
defined characterise temporally bounded populations: total population size, which is the total number of individuals present
within the temporal borders, and total residence time, which is the sum of the residence times of all individuals. We briefly
review methods to estimate these parameters. We illustrate the concept for the large blue butterfly (Maculinea nausithous) and outline insights into ecological and conservation-relevant processes that cannot be gained without the use of the concept. 相似文献
17.
Olivier Duriez Jean-Marie Sachet Emmanuel Ménoni Nathalie Pidancier Christian Miquel Pierre Taberlet 《Conservation Genetics》2007,8(3):513-526
The Western capercaillie (Tetrao urogallus) is a keystone species of Palearctic boreal and altitude coniferous forests. With the increase of mountain leisure activities
and habitat loss, populations are declining in most mountain ranges in Western Europe. Recent work has shown that the populations
from the Pyrenees and Cantabrian Mountains survived a severe bottleneck during the 19th century, and are still considered
as threatened due to habitat fragmentation and isolation with other populations. We present an extensive phylogeographic study
based on mitochondrial DNA sequence (control region) extracted non-invasively from faeces collected throughout the species
range (from western European mountains to central and eastern Europe, Fenno-Scandia, Russia and Siberia). We also compared
our results with DNA sequences of closely related black-billed capercaillie (T. parvirostris). We found that populations from Pyrenees and Cantabrians are closely related but are different from all other capercaillie
populations that form a homogenous clade. Therefore, we consider that these South-Western populations should be considered
as forming an Evolutionary Significant Unit that needs an appropriate management at a local scale. We also discuss the possible
locations of glacial refugia and subsequent colonisation routes in Eurasia, with a Western “aquitanus” lineage from Iberia and Balkans, and an Eastern “urogallus” lineage from Southern Asia. This work might have important implication for capercaillie conservation strategies to define
important areas for conservation, and to prevent possible exchange or introductions of individuals originated from other lineages.
Electronic Supplementary Material The online version
of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
18.
Miguel A. Pérez-Farrera Andrew P. Vovides Pablo Octavio-Aguilar Jorge González-Astorga Jesús de la Cruz-Rodríguez Rigoberto Hernández -Jonapá Susana Maza Villalobos-Méndez 《Plant Ecology》2006,187(1):97-108
The cycad Ceratozamia mirandae is endemic to Chiapas, Mexico. Demographic studies were made in two of its populations in the Sepultura Biosphere Reserve under different conservation conditions; in the nucleus zone “Tres Picos” (conserved) and buffer zone “La Sombra” (disturbed and under management). Spatial distribution of C. mirandae was aggregated, showed a clumped local distribution on shallow soils on steep slopes and male and female cones appear to be synchronous in both populations. The population structure was of type I (Bongers) for both sites. Individuals between the sites showed differences in growth pattern. The oldest plants (80–90 cm tall) were estimated to be about 490 years at “La Sombra”. The finite growth rate () in the buffer zone population showed a tendency for decrease whilst in the nucleus zone this estimate remained stable. The highest elasticity values lied in the transition of the first three classes of the “La Sombra” population, in “Tres Picos” this corresponded to adult plants between 20 and 30 cm tall. Given the above, it is proposed that in the nucleus zone, reproductive adults should be of highest conservation priority, whereas in the buffer zone seedling reintroduction should be carried out regularly until the population increases. We recommend an IUCN Red List category of Vulnerable (VU C, 2a), largely due to difficult-to-control destructive annual forest fires that occur in this Reserve. 相似文献
19.
N. Rashevsky 《Bulletin of mathematical biology》1947,9(1):1-8
We may consider that most of the human behavior is a set of learned responses to certain patterns which recur frequently in
the course of human life. Some “abnormal” events or experiences may result in the learning of abnormal responses, and thus
in abnormal behavior. The “abnormal” responses may begin to be learned after some of the normal response patterns have been
fairly well established. The development of both normal and abnormal behavior may thus be represented by learning curves of
the type studied by H. D. Landahl. Applying some of the results of the theory of learning curves and considering that the
normal and abnormal reactions may reciprocally inhibit each other, a quantitative theory of some psychoses may be developed.
In particular, the effects of shock may be deduced from the assumption that they cause the more recently learned abnormal
reactions to be “unlearned” more readily, than the earlier learned “normal” reactions. The effectiveness of shock treatments
as a function of the duraction of psychosis is discussed from this point of view. 相似文献
20.
Damian O. Elias Bruce R. Land Andrew C. Mason Ronald R. Hoy 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2006,192(8):799-800
Animals emit visual signals that involve simultaneous, sequential movements of appendages that unfold with varying dynamics in time and space. Algorithms have been recently reported (e.g. Peters et al. in Anim Behav 64:131–146, 2002) that enable quantitative characterization of movements as optical flow patterns. For decades, acoustical signals have been rendered by techniques that decompose sound into amplitude, time, and spectral components. Using an optic-flow algorithm we examined visual courtship behaviours of jumping spiders and depict their complex visual signals as “speed waveform”, “speed surface”, and “speed waterfall” plots analogous to acoustic waveforms, spectrograms, and waterfall plots, respectively. In addition, these “speed profiles” are compatible with analytical techniques developed for auditory analysis. Using examples from the jumping spider Habronattus pugillis we show that we can statistically differentiate displays of different “sky island” populations supporting previous work on diversification. We also examined visual displays from the jumping spider Habronattus dossenus and show that distinct seismic components of vibratory displays are produced concurrently with statistically distinct motion signals. Given that dynamic visual signals are common, from insects to birds to mammals, we propose that optical-flow algorithms and the analyses described here will be useful for many researchers.Damian O. Elias and Bruce R. Land contributed equallyAn erratum to this article can be found at 相似文献