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1.
Mao-feng Yue Ren-chao Zhou Ye-lin Huang Guo-rong Xin Su-hua Shi Li Feng 《Journal of Plant Biology》2010,53(2):165-171
High levels of genetic variation enable species to adapt to changing environments and provide plant breeders with the raw
materials necessary for artificial selection. In the present study, six AFLP primer pairs were used to assess the genetic
diversity of Desmodium triflorum (L.) DC. from 12 populations in South China. A high percentage of polymorphic loci (P = 76.16%) and high total gene diversity (H
T = 0.310) were found, indicating that the genetic diversity of D. triflorum is high at the species level. Genetic diversity was also relatively high at the population level (P = 55.85%, H
e = 0.230). The coefficient of gene differentiation among populations (G
ST) was 0.255, indicating that while most genetic diversity resided within populations, there was also considerable differentiation
among populations. AMOVA also indicated 24.29% of the total variation to be partitioned among populations (ΦST = 0.243). UPGMA clustering analysis based on genetic distances showed that the 12 populations could be separated into three
subgroups: an eastern, a western, and a central-southern subgroup. However, a Mantel test revealed no significant correlation
(r = 0.286, p = 0.983) between the geographical distances and genetic distances separating these populations; mountain barriers to gene
flow and human disturbance may have confounded these correlations. The present study has provided some fundamental genetic
data that will be of use in the exploitation of D. triflorum. 相似文献
2.
Fengjuan Zhao Fuli Liu Jidong Liu Put O. AngJr. Delin Duan 《Journal of applied phycology》2008,20(2):191-198
Sargassum muticum is important in maintaining the structure and function of littoral ecosystems, and is used in aquaculture and alginate production,
however, little is known about its population genetic attributes. In this study, random amplified polymorphic DNA (RAPD) and
inter-simple sequence repeat (ISSR) markers were used to investigate the genetic structure of four populations of S. muticum and one outgroup of S. fusiforme (Harv.) Setchell from Shandong peninsula of China. The selected 24 RAPD primers and 19 ISSR primers amplified 164 loci and
122 loci, respectively. Estimates of genetic diversity with different indicators (P%, percentage of polymorphic loci; H, the expected heterozygosity; I, Shannon’s information index) revealed low or moderate level of genetic variations within each S. muticum population, and a high level of genetic differentiations were determined with pairwise unbiased genetic distance (D) and fixation index (F
ST
) among the populations. The Mantel test showed that two types of matrices of D and F
ST
were highly correlated whether from RAPD (r = 0.9706, P = 0.009) or ISSR data (r = 0.9161, P = 0.009). Analysis of molecular
variance (AMOVA) was conducted to apportion the variations among and within the S. muticum populations. It indicated that variations among populations were higher than those within populations, being 55.82% verse
44.18% by RAPD and 55.21% verse 44.79% by ISSR, respectively. Furthermore, the Mantel test suggested that genetic differentiations
among populations were related to the geographical distances (r > 0.6), namely, conformed to the IBD (isolation by distance)
model, as expected from UPGMA (unweighted pair group method with arithmetic averages) cluster analysis. On the whole, the
high genetic structuring among the four S. muticum populations along the distant locations was clearly indicated in RAPD and ISSR analyses (r > 0.9, P < 0.05) in our study. 相似文献
3.
Founder group size is of prime importance in tree breeding programs. We determined whether sampling 20-plus trees for breeding
in Allanblackia floribunda, a tropical forest tree species that has been recently enrolled in tree improvement program for fruit and seed production,
would affect neutral genetic diversity and inbreeding level in both breeding and production populations. Using eight informative
microsatellite loci, we: (a) assessed the nuclear genetic diversity of ten natural populations, and of the breeding population
in the humid forest zone of Cameroon; (b) investigated temporal effective-size fluctuations in A. floribunda natural populations, with a view to identifying the role of past demographic events in the genetic structure of the studied
species; and (c) tested the hypothesis that genetic diversity in a founder group of 20 individuals is not different from that
existing in the wild. The eight loci were variable. High levels of genetic diversity (A = 4.96; H
E = 0.59) and moderate differentiation (R
ST = 0.061) were found within and among populations in wild stands. High genetic distances existed between populations
( \textaverage chord distance = 0.\text2769 ±0.00\text554 ) \left( {{\text{average chord distance}} = 0.{\text{2769}} \pm 0.00{\text{554}}} \right) . Eight of the ten surveyed populations showed signs of deviation from mutation-drift equilibrium, suggesting Pleistocene
population bottlenecks and fluctuations in effective population size. Mantel tests did not reveal any relationships between
genetic and geographic distances. A neighbor-joining dendrogram showed a population structure that could be explained by historical
factors. The hypothesis tested has been accepted. However, a slight increase in inbreeding was observed in the breeding population. 相似文献
4.
Genetic variation of four populations of Sargassum thunbergii (Mert.) O. Kuntze and one outgroup of S. fusiforme (Harv.) Setchell from Shandong peninsula of China was studied with random amplified polymorphic DNA (RAPD) and inter-simple
sequence repeat (ISSR) markers. A total of 28 RAPD primers and 19 ISSR primers were amplified, showing 174 loci and 125 loci,
respectively. Calculation of genetic diversity with different indicators (P%, percentage of polymorphic loci; H, the expected heterozygosity; I, Shannon’s information index) revealed low or moderate levels of genetic variations within each S. thunbergii population. High genetic differentiations were determined with pairwise Nei’s unbiased genetic distance (D) and fixation index (F
ST
) between the populations. The Mantel test showed that two types of matrices of D and F
ST
were highly correlated, whether from RAPD or ISSR data, r = 0.9310 (P = 0.008) and 0.9313 (P = 0.009) respectively. Analysis of molecular variance (AMOVA) was used to apportion the variations between and within the
S. thunbergii populations. It indicated that the variations among populations were higher than those within populations, being 57.57% versus
42.43% by RAPD and 59.52% versus 40.08% by ISSR, respectively. Furthermore, the Mantel test suggested that the genetic differentiations
between the four populations were related to the geographical distances (r > 0.5), i.e., they conformed to the IBD (isolation by distance) model, as expected from UPGMA (unweighted pair group method
with arithmetic averages) cluster analysis. As a whole, the high genetic structuring between the four S. thunbergii populations along distant locations was clearly indicated in the RAPD and ISSR analyses (r > 0.8) in our study. 相似文献
5.
Mattias Olsson John J. Cox Jeffery L. Larkin Per Widén Anders Olovsson 《European Journal of Wildlife Research》2011,57(2):241-249
Increasingly, wildlife managers and land managers are challenged to maintain the viability of large mammal populations. Although
the moose (Alces alces) is an ecologically, economically, and culturally important ungulate species found throughout most of Sweden, little is known
about its ecology throughout the southern part of the country. We collected baseline ecological data on spatial and habitat
use patterns in urbanized southwestern Sweden by fitting 22 adult moose (13 F, nine M) with global positioning system (GPS)
radio collars. Home range size of cows did not differ among seasons (P > 0.10); however, bulls had larger home ranges during fall than all other seasons (P < 0.010). Mean home range size of males during fall and spring was larger than females during any season (P < 0.010). We used a Euclidean distance-based approach to analyze multi-scale habitat selection by moose. Moose of both sexes
and during all seasons selected boreal forest and mires when establishing a home range (P < 0.10). Moose had seasonal differences in habitat selection within their home range (P 0.001), and generally selected clear-cuts and early successional forests, mature coniferous forests, and glades, but avoided
agricultural areas and open water. Habitat and space use characteristics of moose in our urbanizing study area were similar
to characteristics reported for moose in forest-dominated landscapes of Fennoscandia. 相似文献
6.
The dispersal of individuals among populations affects the demographic and adaptive trajectories of animal populations and is fundamental to understanding population dynamics. White-tailed ptarmigan (Lagopus leucura) are a high elevation grouse species that live year-round in patchily distributed alpine areas in western North America. We investigated the patterns of dispersal and identified barriers to gene flow for a threatened subspecies (L. l. saxatilis) endemic to Vancouver Island, Canada. Connectivity among seven sites was examined using nine microsatellite loci (n = 133 individuals, H(O) = 0.62, mean number of alleles = 10) and direct movement observations using radio-telemetry (n = 118 individuals). Average movement distances of individuals measured by radio-telemetry were 0.63-3.23 km and considerably less than the shortest distance between sampling sites (18 km). Furthermore, despite extensive radio-telemetry data, movement was never observed between any of the seven sampling sites. In contrast, genetic results (STRUCTURE, TESS) showed connectivity among most of the seven sampling sites and suggested that genetic variation is best explained by two clusters of individuals which separated the South sampling site from all other areas of Vancouver Island. Analysis of molecular data also showed a generally consistent pattern of isolation by distance (Mantel test r = 0.11, P < 0.01) with large areas of unsuitable low elevation habitat possibly acting as barriers to gene flow. Despite the naturally subdivided distribution of populations, white-tailed ptarmigan do not fit well into any common definition of a metapopulation. We conclude the incongruities between the genetic and radio-telemetry data are best explained by episodic dispersal patterns. In this study, we demonstrated the importance of combining genetic and ecological data in understanding patterns of dispersal and population structure. 相似文献
7.
Wiebke Neumann Göran Ericsson Holger Dettki 《European Journal of Wildlife Research》2009,55(3):255-265
Previous studies on moose Alces alces have suggested that interactions with humans may trigger anti-predator behaviors and generate a demographical cost. Therefore,
we hypothesized that disturbances from small and big game hunting may have negative effects on moose movements, diurnal activity,
and activity range. Using location data from 64 moose equipped with GPS collars from three populations (Low Alpine, Inland,
Coastal) with different temporal human presence and spatial accessibility, we evaluated the impact of hunting on moose activity
rhythms. On average, female moose in the low human population density (Low Alpine) area (<0.5/km2) had significantly lower movement rates during moose hunting season, but variation in movement rates among individuals were
higher compared with female moose in regions with denser human populations (6–24/km2). We found no evidence that reproductive status influenced female moose sensitivity to disturbance. As expected, females
used smaller activity ranges and were less active nocturnally than males. The high within-group variation suggests that current
hunting disturbance levels do not alter moose population behavior in general. Our data indicate that alterations in movement
were related to rutting activity, not human disturbance induced by hunting. In line with behavioral theory, our study suggests
that some individuals were more sensitive to hunting disturbance than the general population. Our work suggests that individual
moose may perceive human predation risk to be similar to other predation risks. 相似文献
8.
We assessed genetic variation in a total of 22 populations of the tree species Cordia africana Lam. in Ethiopia and analyzed the country-wide impact of population history, forest disturbance and alteration of land use
on extant intraspecific diversity. Amplified Fragment Length Polymorphisms (AFLPs) and chloroplast microsatellite markers
were investigated. The analyses of the AFLP data revealed high diversity in all investigated populations: the percentage of
polymorphic loci (PPL) ranged from 62.2% to 92.2% and Nei's gene diversity from 0.220 to 0.320 within the populations. The
mean PPL and the mean diversity within populations were 85.7% and 0.287, respectively. The analysis of molecular variance
revealed a moderate level of differentiation (ΦST = 0.07, p < 0.001) among the populations. The Mantel test proved a significant but low correlation (r = 0.31, p < 0.001) between the geographic distance and the genetic differentiation matrices. Only three different cpDNA haplotypes
were observed; no more than two haplotypes were found in any population. The dominant haplotype with an overall frequency
of 81% was observed in all populations. The level of differentiation among the populations was comparatively low at chloroplast
DNA (G
ST = 0.18, R
ST, N
ST = 0.22). The observed patterns and levels of genetic variation within and among the populations indicate that efficient gene
flow via pollen and seed is likely to be the main factor contributing to the maintenance of genetic diversity in natural and
disturbed conditions. 相似文献
9.
Yeong-Seok Jo Soo-Rang Lee John Thomas Baccus Jongwoo Jung Michael R. J. Forstner 《Ecological Research》2018,33(5):989-999
The cognizing of connectivity among small mammal populations across heterogeneous landscapes is complicated due to complex influences of landscape and anthropogenic factors on gene flow. A landscape genetics approach offers inferences on how landscape features drive population structure. Through a landscape genetics approach, we investigated influences of geographical, environmental, and anthropogenic features on populations of Apodemus agrarius, the striped field mouse, the prime vector of hemorrhagic fever by a landscape genetic approach. We identified landscape features that might affect the population structure of striped field mice by analyzing microsatellite markers of 197 striped field mice from 21 populations throughout South Korea. We developed Maximum-likelihood population effects models based on landscape distances and resistance matrices and pairwise FST values for meta-populations of striped field mouse. We also conducted Mantel and partial Mantel tests to investigate geographic patterns of genetic similarities. In Mantel and partial Mantel tests, the FST was significantly correlated with all three models of movement; movement cost, Euclidian distance and least-cost distance, although the magnitudes of correlations varied. The 4 top-ranked models included three variables; temperature, precipitation and one human disturbance factor (population). We did not attain a significant effect for anthropogenic factors on genetic similarities among populations in the Korean striped field mouse, but we confirmed a significant association for genetic similarity with climatic features (temperature and precipitation). 相似文献
10.
Climatic oscillations during the Quaternary strongly affected the distribution of warm-temperate tree species, which experienced
local restrictions into ice-free areas and posterior expansions. To evaluate the impact of these range movements on the genetic
structure of populations, we performed a phylogeographical analysis of the species Nothofagus obliqua with chloroplast DNA markers. A total of 27 populations covering the whole natural distribution range were analyzed using
polymerase chain reaction-restriction fragment length polymorphism. Diversity (h
T, h
S), allelic richness (r
g), and differentiation among populations for unordered (G
ST) and ordered alleles (N
ST) were calculated. The relationships among haplotypes were evaluated by the construction of a minimum spanning network. The
spatial distribution of the genetic variation was analyzed through a Mantel test and with a nested analysis of molecular variance
to differentiate between geographic regions. The screening of 11 non-coding regions allowed the identification of 14 haplotypes.
A high genetic differentiation was detected (N
ST = 0.875 and G
ST = 0.824) with the existence of phylogeographic structure (p < 0.05). The distribution of the genetic variation was partially explained by the topography of the region when the populations
were divided longitudinally into Coastal Mountains, Central Valley, and Andes Mountains (ϕ
RT = 0.093, p = 0.001). In agreement with pollen records, our results support the hypothesis of Coastal refuges since the region harbors
high diversity together with older and private haplotypes. Long-lasting persistence of some Coastal populations without contribution
to re-colonization is proposed. Additional refuges are also postulated along the Andes and Longitudinal Valley. Survival in
multiple glacial refuges is discussed together with the possible migratory routes. 相似文献
11.
The aim of the present study was to assess the degree of genetic variation and divergence among six populations of Calomys hummelincki, a phyllotine rodent distributed in northern South America. With this information we will try to evaluate the two hypotheses
of possible colonization and differentiation of this group of rodents postulated by Baskin and Reig. We studied 34 loci by
electrophoretic analysis: 21 were monomorphic for all populations and 13 were polymorphic in at least one population, being
P
1% = 21.6% the mean value for all populations. The mean value of heterozygosity per locus was H = 0.075. Low values of genetic distance were observed among populations of the Llanos region (0.001 < D < 0.006). There was a larger genetic distance (D = 0.024) between the population from Isiro, in the northwestern semiarid region, and those from the Llanos region. The insular
population of Aruba displayed the lowest value of genetic distance with the population from Isiro (D = 0.014). The specimens from Sipao, on the right side of the Orinoco river, displayed the highest values of genetic distances
in comparison with other populations of C. hummelincki (0.070 < D < 0.095). The relatively high differentiation was due to the fixation of new alleles, not found in other populations of C. hummelincki, at loci Idh-1 and Est-2. F-statistics and Nm values indicated reduced gene flow among the populations sampled. Despite the limited data, the results
seem to support Reig's hypothesis about south to north colonization of genus Calomys in South America.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
A. Allan Degen Luma Nidhi Pandey Michael Kam Shambhu B. Pandey Chet R. Upreti Netra P. Osti 《Human ecology: an interdisciplinary journal》2010,38(5):625-637
More than 50% of Nepal’s population lives in the hill regions, usually with small land holdings, and over 60% are considered
below the poverty line. Livestock, and particularly goats, provide these small-scale farmers with about 55% of their on-farm
income. We studied goat production in Katteldanda, a mid-hill village of 78 households, mainly Brahmins, in Ghorka District.
Subsistence farmers raise six or seven goats and one or two buffalo, and cultivate mainly maize, millet and rice. Tree fodder
constituted about 70% of dry matter intake of goats for large parts of the year and was collected by lopping branches from
trees on upland, rain-watered, private terraces (bari) near the household compound. Local farmers ranked the fodder trees they considered best and we measured the actual fodder
they offered to goats. In addition, we evaluated and ranked 23 fodder species on the basis of laboratory in vitro nutritional
and metabolizable energy yields. Using a Mantel test, a significant correlation was found between what the farmers thought
was best fodder and fodder offered to goats (Mantel r = 0.398; P = 0.037) but non-significant correlations were found between either what the farmers thought was best fodder or fodder offered
to goats and laboratory rankings (Mantel r = −0.027; P = 0.49 and Mantel r = 0.187; P = 0.18, respectively). We concluded that biomass produced and availability throughout the year, in addition to nutritional
and energy yield, are important criteria for selecting fodder trees for goat production. 相似文献
13.
Ti Feng Shan Shao Jun Pang Yu Rong Zhang Irina M. Yakovleva Anna V. Skriptsova 《Journal of applied phycology》2011,23(1):35-45
The genetic diversity and relationships of six representative cultivars and six geographically isolated wild populations
of Saccharina japonica along the northwest coasts of the Pacific Ocean were investigated using AFLP markers. A total of 547 bands were generated
across all samples by ten primer combinations. At the cultivar or population level, the percentage of polymorphic loci (P), gene diversity (H), and Shannon’s information index (I) was highest in Dalian population (P 59.05%; H 0.2057; I 0.3062) and lowest in Lianjiang cultivar (P 9.87%; H 0.0331; I 0.0497). At the species level, P, H, and I were 85.01%, 0.1948, and 0.3096, respectively. Unique bands were detected in all the six wild populations, with Dalian being
the most. In comparison, only Yanza cultivar possessed one unique band. The G
ST
value was 0.6226 and the gene flow (N
m
) was 0.1515, indicating strong genetic differentiation among cultivars and populations. Two UMPGA dendrograms were constructed
based on the Dice similarity coefficients among individuals and on genetic distances among cultivars and populations, which
generally revealed three major clades corresponding to three countries. Analysis of molecular variance revealed that a larger
proportion (60.21%) of the total genetic variation was attributable to differences among cultivars and populations. The Mantel
test suggested that genetic differentiation was positively correlated with geographic distance (r = 0.7962, P = 0.011) in the six wild populations, agreeing with the isolation by distance model. On the whole, low to moderate genetic
diversity within cultivars and populations (except Dalian population) and high genetic differentiation among cultivars and
populations were detected. 相似文献
14.
CATHERINE LAURIAN CHRISTIAN DUSSAULT JEAN-PIERRE OUELLET RÉHAUME COURTOIS MARIUS POULIN LAURIER BRETON 《The Journal of wildlife management》2008,72(5):1094-1100
Abstract: Sodium has many fundamental physiological functions in animals but is rare in boreal ecosystems where moose (Alces alces) thrive. In Québec (Canada), sodium is readily available in aquatic vegetation and in salt pools that form along highways. We do not know if moose are adopting specific behaviors to access sodium sources or if they simply use the sodium sources they encounter during their movements. We tested the hypothesis that moose modify both space and habitat use to gather sodium from salt pools. We expected moose to use salt pools mostly in spring and early summer, when needs are greatest and before aquatic vegetation has fully developed. We fitted 47 moose with Global Positioning System telemetry collars and collected data for 2 to 36 months between 2003 and 2006. We rarely located moose at salt pools (0.12% among the 95,007 locations collected). As we expected, use of salt pools was highest in late spring and in early summer, and we observed a time lag between peak use of salt pools compared to use of lakes and waterways, indicating moose fulfilled their sodium requirements in salt pools before aquatic vegetation was available. Moose selected salt pools over lakes and waterways when these 2 sodium sources were present in their home range and moved rapidly over large distances to reach them. Our results were consistent with moose using salt pools when they are likely to be sodium deficient. Salt pools were less accessible, required long-distance movements, and were located in habitually avoided areas along highways. Elimination of roadside salt pools should be considered among strategies to reduce cervid-vehicle collision risks in boreal environments. 相似文献
15.
Inhibited dispersal, leading to reduced gene flow, threatens populations with inbreeding depression and local extinction. Fragmentation may be especially detrimental to social insects because inhibited gene flow has important consequences for cooperation and competition within and among colonies. Army ants have winged males and permanently wingless queens; these traits imply male‐biased dispersal. However, army ant colonies are obligately nomadic and have the potential to traverse landscapes. Eciton burchellii, the most regularly nomadic army ant, is a forest interior species: colony raiding activities are limited in the absence of forest cover. To examine whether nomadism and landscape (forest clearing and elevation) affect population genetic structure in a montane E. burchellii population, we reconstructed queen and male genotypes from 25 colonies at seven polymorphic microsatellite loci. Pairwise genetic distances among individuals were compared to pairwise geographical and resistance distances using regressions with permutations, partial Mantel tests and random forests analyses. Although there was no significant spatial genetic structure in queens or males in montane forest, dispersal may be male‐biased. We found significant isolation by landscape resistance for queens based on land cover (forest clearing), but not on elevation. Summed colony emigrations over the lifetime of the queen may contribute to gene flow in this species and forest clearing impedes these movements and subsequent gene dispersal. Further forest cover removal may increasingly inhibit Eciton burchellii colony dispersal. We recommend maintaining habitat connectivity in tropical forests to promote population persistence for this keystone species. 相似文献
16.
Francesca Gherardi Federica Tarducci Marco Vannini 《Ethology : formerly Zeitschrift fur Tierpsychologie》1988,77(4):300-316
Locomotor activity in a field population of the freshwater crab, Potamon fluviatile, was studied during the breeding season by means of radio-telemetry and by direct counts of active animals along a transect of the stream. The basic pattern of crabs' locomotor activity can be described as a sequence of short distance movements around the shelters (foraging movements), followed by rarer long distance displacements (wandering movements). Whilst direct counting showed that the crabs exhibit a broadly nocturnal rhythm in foraging movements, no daily periodicity in wandering activity was revealed by telemetry. There is sexual difference in these latter excursions: females move farther along the stream and into the surrounding terrestrial habitat than do males. This behaviour is in contrast to observations made during the non-breeding season and is probably related to the stage of female reproduction. 相似文献
17.
Hedia Bourguiba Lamia Krichen Jean-Marc Audergon Bouchaib Khadari Neila Trifi-Farah 《Plant Molecular Biology Reporter》2010,28(4):578-587
The impact of mapped microsatellites on the study of genetic diversity of Tunisian apricot accessions was assessed. The genetic
variability of 47 traditional apricot cultivars originating from several areas in Tunisia was investigated with 32 polymorphic
microsatellite loci selected for their location throughout the eight linkage groups of Prunus genome. The higher polymorphism and greater transportability of these markers among Prunus species were proved by the expected heterozygosity (He = 0.56) and Shannon’s index of diversity (I = 1.05), indicating that Tunisian apricot germplasm maintained a substantial level of genetic diversity. According to their
geographical origin, the genetic differentiation among groups (north, center, and south; Fst = 0.04) was lower, while the
gene flow among groups was consequent (Nm = 4.79), attesting a narrow genetic background of apricot in the country. Both unweighted
pair-group method with arithmetic mean dendrogram, based on Nei’s genetic distances and factorial correspondence analysis,
separated northern cultivars from central and southern cultivars, revealing the same molecular basis of apricot material in
the Center and the South of Tunisia. These results revealed the efficiency of mapped markers for genetic variability measurements
compared to randomly ones, however, no advantage was observed considering the genetic relationships among studied accessions. 相似文献
18.
Dispersal is a key determinant of the evolution and ecology of species. For a comprehensive picture of dispersal, a combination
of both field observations and indirect genetic measures are required, as both of these have strengths that may mitigate the
other’s limitations. Here, we used microsatellite markers and radio-telemetry data to study dispersal and gene flow in Siberian
flying squirrels. Genetic data confirmed our empirical results that dispersal is female biased in the flying squirrel. Female
bias in dispersal is exceptional among mammals and in flying squirrels is probably explained by competition for food resources
and nesting cavities among mothers and daughters. The individual-level genetic pattern was influenced by isolation by distance.
Using this information fairly comparable dispersal distances were derived using indirect data as observed directly with radio
telemetry. Thus, our results support the recent conclusion that individual-level genetic data can be useful in inferring dispersal
distances for species for which direct data are lacking. 相似文献
19.
Kerry L. Nicholson Paul R. Krausman Adrian Munguia-Vega Melanie Culver 《European Journal of Wildlife Research》2011,57(6):1151-1163
Spatial and temporal interactions among individual members of populations can have direct applications to habitat management
of mountain lions (Puma concolor). Our objectives were to evaluate home range overlap and spatial/temporal use of overlap zones (OZ) of mountain lions in
Arizona. We incorporated spatial data with genetic analyses to assess relatedness between mountain lions with overlapping
home ranges. We recorded the space use patterns of 29 radio-collared mountain lions in Arizona from August 2005 to August
2008. We genotyped 28 mountain lions and estimated the degree of relatedness among individuals. For 26 pairs of temporally
overlapping mountain lions, 18 overlapped spatially and temporally and eight had corresponding genetic information. Home range
overlap ranged from 1.18% to 46.38% (
[`(x)] = \text24.\text43 \overline x = {\text{24}}.{\text{43}} , SE = 2.96). Male–male pairs were located within 1 km of each other on average, 0.04% of the time, whereas male–female pairs
on average were 3.0%. Two male–male pairs exhibited symmetrical spatial avoidance and two symmetrical spatial attractions
to the OZ. We observed simultaneous temporal attraction in three male–male pairs and four male–female pairs. Individuals from
Tucson were slightly related to one another within the population (n = 13, mean R = 0.0373 ± 0.0151) whereas lions from Payson (n = 6, mean R = −0.0079 ± 0.0356) and Prescott (n = 9, mean R = −0.0242 ± 0.0452) were not as related. Overall, males were less related to other males (n = 20, mean R = −0.0495 ± 0.0161) than females were related to other females (n = 8, mean R = 0.0015 ± 0.0839). Genetic distance was positively correlated with geographic distance (r
2 = 0.22, P = 0.001). Spatial requirements and interactions influence social behavior and can play a role in determining population density. 相似文献
20.
Sixty nine hammerhead sharks, Sphyrna lewini, were tagged at Malpelo Island (Colombia) with ultrasonic transmitters during March 2006, 2007 and 2008, as part of a study
to understand their residency at the island and their horizontal and vertical movements. Five sharks visited Cocos Island,
627 km distant from Malpelo. One of the sharks that appeared at Cocos Island also visited the Galapagos Islands, 710 km from
Cocos, a month later. There is connectivity of Sphyrna lewini between Malpelo, Cocos and the Galapagos Islands, but the frequency of movements between the islands appears to be relatively
low (<7% of the tagged sharks). The most common depth at which the sharks swam coincided with the thermocline (rs = 0.72, p < 0.01). The depth of the thermocline varied depending on the time of the year. Nocturnal detections of the sharks were more
frequent during the cold season than during the warm season (W = 60, p < 0.01). We also found that hammerheads spent significantly more time on the up-current side of the island (Kruskal-Wallis = 31.1008;
p < 0.01). This study contributes to the knowledge of hammerhead sharks not only in Malpelo Island but also at a regional level
in the Eastern Tropical Pacific. 相似文献