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1.
Marie-Claire Fleury-Brugiere David Brugiere 《International journal of primatology》2010,31(3):383-392
The Republic of Guinea harbours the largest population of the endangered western chimpanzees Pan troglodytes verus, and the conservation of this population is regarded as a regional priority. Chimpanzees occur in 3 of the 5 protected areas
in Guinea but their conservation status is unknown. We conducted a chimpanzee census in 2001–2002 in the Haut Niger National
Park (HNNP), the largest protected area in the country. We counted nests along a total of 103.83 km of transects in the Mafou
forest, 1 of the 2 core areas of the park. We recorded a total of 823 nests, of which 38.1% were located in gallery forests,
although this habitat type covers only 4.2% of the study site. Using a site-specific mean nest decay rate of 194 days, we
estimated the mean density of chimpanzees in the study area at 0.87 weaned individuals/km2, the highest density recorded in
any West African protected area. A survey conducted in 2008–2009 by other authors in the Mafou forest suggests that the chimpanzee
population remained stable over the last 6 yr. Given the significance of the chimpanzee population of the HNNP at the national
and international levels, we provide recommendations for its conservation over the long term. Our results highlight the importance
of gallery forests as key habitat for chimpanzees in the savannah biome. We therefore recommend that more attention be paid
to the conservation of this habitat in land management and conservation planning schemes. In particular, we recommend setting
aside gallery forests as ecological corridors between nearby protected areas to maintain exchange between distant chimpanzee
populations. 相似文献
2.
The rate of predation on mammals by chimpanzees was determined from carcasses and from fecal specimens found on fresh trails
during a 16-month period in the montane forest of Kahuzi-Biega National Park, Zaire. A unit-group of semi-habituated chimpanzees,
composed of 22 – 23 individuals including 8 adult or adolescent males, appeared to kill about 18 – 30 mammalian prey (16 –
28Cercopithecus monkeys) per year, if the multiple kills by chimpanzees were not considered. A juvenile l'Hoest's monkey was recorded for
the first time as the prey of chimpanzees in this study. Predation occurred in the late dry and the early rainy seasons, when
the diversity of ripe fruits was the highest during the year. The Kahuzi chimpanzees tended to kill mammals less frequently
but to killCercopithecus monkeys more frequently than chimpanzees in other habitats. The absence of red colobus monkeys, which are the most frequent
prey in Gombe, Mahale, and Tai, might be responsible for the low predation rate. However, the estimated rate of predation
onCercopithecus monkeys is the highest record among various chimpanzee habitats. At least 11 – 18% of theCercopithecus population seemed to be lost annually as a result of being killed by chimpanzees. Chimpanzees may be the most important predators
on these monkeys in the absence of leopards at Kahuzi. The examination of fecal samples and carcasses suggested that adult
(probably male) or adolescent chimpanzees tended to eat juvenile or subadult monkeys most frequently, as is also seen for
chimpanzees in Gombe, Mahale, and Tai. 相似文献
3.
Rimgaudas Treinys Asko L?hmus Darius Stonius Saulis Skuja Eugenijus Drobelis Bronius ableviius Saulius Rumbutis Deivis Dementaviius Vladas Narueviius Antanas Petraka Danas Augutis 《Journal of Ornithology》2008,149(1):75-81
Recent trends in the European Black Stork Ciconia nigra population are geographically distinct: range expansion and adaptation to human activity dominate in western and central
Europe, while declines—probably induced by landscape change—are reported in the east. We studied the large Lithuanian Black
Stork population in the transition zone to explore whether, and how, the detrimental influences of recent Baltic landscape
changes are balanced by the West European tendency of behavioural adaptation to human activity. Based on monitoring in sample
plots, the current population was estimated at 650–950 pairs, indicating a significant decrease (possibly over 20%) during
the last two decades. In comparison to the Latvian and Estonian populations, however, this decline is smaller, and the reproductive
success remains at a high level [66% breeding success and 2.99 ± 0.97 (SD) fledglings per successful attempt, 2000–2006];
this north–south gradient suggests a climate-mediated impact of habitat degradation in the Baltic countries. The storks are
also nesting closer to forest edges and in younger stands than 15–30 years ago, which has probably reduced the nest-tree limitation,
as indicated by an increased use of large oaks. Thus, habitat degradation and adaptation seem to be taking place simultaneously
in the Lithuanian Black Stork population, as was expected from its geographical location. In general, our study supports the
view that, whenever possible, species conservation strategies and the use of indicator species should be geographically explicit. 相似文献
4.
Paul Marchesi Nathalie Marchesi Barbara Fruth Christophe Boesch 《Primates; journal of primatology》1995,36(4):591-607
Most methods of estimating chimpanzee population densities rely on nest counts. We tested the most frequently used techniques on a known chimpanzee community living in the rainforest of the Taï National Park, Côte d’Ivoire. The best density estimates are given by counts that assume groups of nests to be distributed randomly and that use the mean group size for homogenous habitat but the median for heterogenous habitats. Correction for real forest cover within the region should be made because chimpanzees make nests only in forested regions. This method gave the exact chimpanzee density for the Taï population, i.e. 1.7 nest builders/km2. For the nationwide survey, we first estimated the chimpanzee density for different types of habitat (e.g. intact primary forest: 1.64 chimpanzees/km2; degraded forests: 0.4 chimpanzees/km2; human encroached forests and mosaic habitats: 0.09 chimpanzees/km2). Second, we estimated the total forest cover of the country with satellite pictures. This gave an estimated chimpanzee population in Côte d’Ivoire of about 11,676 ± 1,168 individuals, which equals the number of spectators at a soccer game in an average European town. Sadly, only three National Parks may have chimpanzee populations large enough to be viable, whereas the rest are scattered and isolated small populations that are already threatened in their survival. 相似文献
5.
Tatyana Humle Christelle Colin Matthieu Laurans Estelle Raballand 《International journal of primatology》2011,32(2):456-473
The release of wild or captive-bred mammals within their historical ranges typically aims to reestablish populations in areas
where they have become extinct or extirpated, to reinforce natural populations, or to resolve human–wildlife conflicts. Such
programs, which also typically in parallel help foster the protection of the release site, concern a wide range of endangered
mammalian species, including our closest living relatives: chimpanzees. In June 2008, the Chimpanzee Conservation Center (CCC),
which is located in the High Niger National Park (HNNP) in Guinea, released a group of 12 chimpanzees (Pan troglodytes verus) comprised of 6 females and 6 males (8–20 yr old). The selected release site lies 32 km from the sanctuary in the Mafou,
a core area of HNNP where wild chimpanzees are also known to occur. The purpose of this release was therefore to reinforce
the natural chimpanzee population within the Mafou core area and to promote the protection of the HNNP. Nearly 2 yr postrelease,
9 chimpanzees still remain free-living. Two thirds of the release chimpanzees were equipped with VHF-GPS store-on-board tracking
collars. We used data from retrieved collars to explore the release chimpanzees’ habitat use, individual day range, and core
area use (50% and 80%) during the first year of the release. Males traveled significantly further than females. Although minimum
day range did not differ between the sexes or vary seasonally, some release males were active for longer during the day than
the females. Males also ranged over larger areas and used a wider network of core areas than the females. Habitat use was
similar to that recorded in wild chimpanzees in the HNNP. As of September 2010, 2 males and 3 females form a group at the
release site. Two of these females gave birth to healthy offspring respectively 16 and 20 mo postrelease. Another female successfully
immigrated into a wild chimpanzee community. We suggest that the success of this chimpanzee release can be attributed to the
CCC’s lengthy rehabilitation process and the savanna-mosaic habitat of the HNNP. This release demonstrates that under special
socioecological circumstances, the release of wild-born adult chimpanzees of both sexes is a viable strategy, which can also
function as an effective conservation tool. 相似文献
6.
Xingyi Gao Weikang Yang Jianfang Qiao Jun Yao Kefen Xu 《Frontiers of Biology in China》2008,3(4):385-391
This article presents the distribution and status of bustards, which are listed as first-category protected animals according
to the survey results during 1990–2002 in China. The Chinese populations of Otis tarda dybowskii are breeding in south-west of Heilongjiang Province, western Jilin Province, east and middle Inner Mongolia, north Ningxia
Hui Autonomous Region, and Gansu Province. A few can winter in the south breeding-range. Its winter-range lies from the south
to the Yellow River, as far as to Guizhou Province and Jiangxi Province. Its population number is about 200–300 or 500–800.
The Chinese populations of O. t. tarda are breeding in the north and west of Xinjiang. It is unclear about its winter-range, which is presumed to be in south Asia.
Recently we found individuals wintering in Chabuchaer and west Xinjiang. The population number is about 2000–3000. The habitat
in breeding range includes steppe, grassland, desert grassland, and farmland. The habitat in winter range is the beach of
rivers and lakes, meadows, meadow-grassland, and wheatland. The Chinese populations of Chlamydotis undulata macqueeni are breeding in the fringe of the Jungar Basin, the banks of the Ulungur River, Balikun and south Turpan Basin in Xinjiang,
west Inner Mongolia, and west Gansu. NortheastMulei in eastern Jungar Basin of Xinjiang is the main breeding-range in the
world. The bird uses desert and desert grassland as its habitat. Its winter-range is west Asia and south Asia. Its population
number is about 2000. The Chinese populations of Tetrax tetrax are breeding in north Xinjiang, and China is located on the east border of its breeding-range. Its habitat is grassland and
semi-desert, and its winter-range lies in south Asia. Its population in China is very scarce. In addition, we analyzed the
causes of their endangerment and put forward protection tactics of Chinese Bustards.
__________
Translated from Arid Zone Research, 2007, 24(2): 179–186 [译自: 干旱区研究] 相似文献
7.
Naoki Agetsuma 《International journal of primatology》2007,28(1):97-106
I estimated the minimum area required (MAR) for local populations of Japanese macaques (Macaca fuscata) from empirical data
on habitat area and population viability. I used logistic regression analysis to examine the relationship between habitat
area and survival/extinction among 50 populations over 50 yr. Estimated habitat areas satisfying 95–99% probability of a population
persisting for 100–1000 yr range from 525 to 975 km2. However, confidence limits of parameters in the logistic regression equation are very large. Moreover, the number of extinct
population might be underestimated in the empirical data. Consequently, a much wider habitat area (>1000 km2) should be considered for actual conservation planning for local populations of Japanese macaques. The method involves fewer
variables and assumptions than previous methods of MAR estimation, and therefore may be a more useful way to estimate MAR
for various species and regions. 相似文献
8.
Rates of chimpanzee predation on mammals are calculated using data on 75 kills recorded during focal observation in Gombe
National Park, Tanzania, from January 1972 to April 1975. The chimpanzees were members of two study communities (Kanyawara,
or Northern, and Kahama, or Southern, community), and were observed as focal individuals for 14,583 hr by more than 30 researchers
and field assistants working in pairs. The rate of predation by females was too low to allow reasonable estimates. For males,
the mean rate of killing during the study period was 0.31 kills per male per 100 hr (N=17 males), or 4.65 kills per 100 hr in the two communities. In contrast to results from Mahale Mountains, there was no difference
in predation rate between wet and dry seasons. However, predation rates varied over time, increasing by four times between
the first three and last four seasons of the sample period. In an average year the 15 adult and subadult male chimpanzees
are calculated to have killed 204 prey per year in an area of 16 km2, varying between 99 and 420 prey per year in periods of low and high predation rate. Red colobus were the most frequent prey,
followed by bushpig and bushbuck. Predation rates varied greatly on different prey species, and were not related to either
the proportion of time spent within 200 m of male chimpanzees, or to their population densities. In relation to encounter
rates and population density, baboons, blue monkeys, and redtail monkeys were killed at a fraction of the rate of red colobus
monkeys, which suffered severe mortality from chimpanzee predation. Predation on bushpig and bushbuck also appears to have
been high in relation to population density. The amount of food provided by predation is estimated to have averaged 600 kg
per year for chimpanzees in the two communities (totalling 14–17 adult or subadult males, 18–20 adult of subadult females,
and about 19 infants or juveniles). This suggests that adult males consumed around 25 kg of meat per year, although any average
figure undoubtedly masks considerable individual variation. Present data suggest that chimpanzees in Gombe and Tai National
Park, Ivory Coast, prey on mammals at rates higher than other populations. 相似文献
9.
A total of 24 commercial fields of cabbages and Brussels sprouts were sampled in a grid fashion with 20–25 equally spaced
cells with four plants per cell. Using this data base of 80–100 plants, we conducted computer stimulations to compare the
treatment decisions that would be made for the major insect pests using published sequential sampling programs and a newly
developed variable-intensity sampling program. Additionally, we compared the number of samples required to make the decision.
At low thresholds (10–20%) for both Lepidoptera and cabbage aphids, variable intensity-sampling required a smaller sample
size and provided more reliable decisions, while at high thresholds (40–50%) sequential sampling provided more reliable decisions.
In both procedures, the occurrence of incorrect decisions was minimal. The number of cases in which a decision would not be
reached after a 40-plant sample was lower for variable-intensity sampling. Considering the number of samples required to make
a correct decision and the greater need for reliable decisions at lower thresholds, variable-intensity sampling was superior
to sequential sampling. Additionally, variable-intensity sampling has the advantage of requiring samples to be taken in a
greater area of the field and thus increases the probability of detecting localized infestations. Although variable-intensity
sampling was not designed to classify pest populations for treatment decisions but rather to achieve sampling precision around
the population mean, our present studies indicate that it can also be an effective method to aid in treatment decisions. 相似文献
10.
Guillermo Velo-Antón Mario García-París Adolfo Cordero Rivera 《Conservation Genetics》2008,9(5):1263-1274
The European pond turtle (Emys orbicularis) is threatened and in decline in several regions of its natural range, due to habitat loss combined with population fragmentation.
In this work, we have focused our efforts on studying the genetic diversity and structure of Iberian populations with a fine-scale
sampling (254 turtles in 10 populations) and a representation from North Africa and Balearic island populations. Using both
nuclear and mitochondrial markers (seven microsatellites, ∼1048 bp nDNA and ∼1500 bp mtDNA) we have carried out phylogenetic
and demographic analyses. Our results show low values of genetic diversity at the mitochondrial level although our microsatellite
dataset revealed relatively high levels of genetic variability with a latitudinal genetic trend decreasing from southern to
northern populations. A moderate degree of genetic differentiation was estimated for Iberian populations (genetic distances,
F
ST
values and clusters in the Bayesian analysis). The results in this study combining mtDNA and nDNA, provide the most comprehensive
population genetic data for E. orbicularis in the Iberian Peninsula. Our results suggest that Iberian populations within the Iberian–Moroccan lineage should be considered
as a single subspecies with five management units, and emphasize the importance of habitat management rather than population
reinforcement (i.e. captive breeding and reintroduction) in this long-lived species. 相似文献
11.
Report on the distribution,population, and ecology of the yunnan snub-nosed monkey (Rhinopithecus bieti) 总被引:2,自引:0,他引:2
Yongcheng Long Craig R. Kirkpatrick Zhongtai Xiaolin 《Primates; journal of primatology》1994,35(2):241-250
The Yunnan snub-nosed monkey (Rhinopithecus bieti), an endangered species in China, has received more protection in theory than in practice. Therefore it is on the very verge
of extinction. The population of the species was estimated less than 2,000 individuals spread in 19 distinct groups. It was
confirmed that the monkey was confined to the Yunling Mountain System, the area between the Yangtze River (Changjiang, aka
Jinshajiang) to the east and the Mekong River (Lancangjiang) to the west. We further concluded that a lowland belt to the
east, about 100 km long and 20 – 30 km wide was not suitable habitat for the monkeys, and appeared to serve as the natural
ecogeologic barrier for the species. Our results indicated that the southern limit of the distribution was at Longma (26°14′N),
and that the northern limit of the distribution was at Xiaochangdu (29°20′N). The distribution area of the species was substantially
smaller than previously estimated. There were substantial ecological differences between the southern and northern parts of
the species range. The monkey was found only in fir-larch forest. 相似文献
12.
Population responses of Japanese serow (Capricornis crispus) to clear-cut logging and planted tree growth were studied by a direct count of the number observed in three areas, Takiyama
(305 ha), Gentouziro (270 ha), and Tanokashira (324 ha), near Wakinosawa Village, Aomori Prefecture, Japan, during 1976–89.
At Takiyama, a mature mixed forest ofThujopsis dolabrata var.hondai andFagus crenata decreased from 73 to 39% coverage of the area due to clear-cutting during 1978–83. The serow population maintained a relatively
low stable density (3–6 individuals per km2) until 1985–87, and increased 5–10 years after the clear-cutting, reaching 9–10 km−2 in 1988. At Gentouziro and Tanokashira, young plantations of Japanese cedar (Cryptomeria japonica) covered about half of each area. The population densities between 1980 and 1983 were relatively high (14–19 km−2), but declined thereafter, reaching 10–14 km−2 in 1988–89. These results indicated that the density increase resulted from an improvement of food supply due to growth of
scrub following the clear-cutting, and that the density decline resulted from a habitat change due to growth of planted Japanese
cedar and a decrease in the food supply. In Wakinosawa Village, serow density began to increase 5–10 years after forest cutting,
and the high population density, about three- or six-fold larger than that in mature forest, is expected to be maintained
for about 20 years after logging. 相似文献
13.
Kay H. Farmer Hannah M. Buchanan-Smith Aliette Jamart 《International journal of primatology》2006,27(3):747-765
As wild primate populations decline, numbers of orphaned primates, sanctuaries, and attempts to release primates back to the natural environment increase. Release projects frequently are poorly documented despite IUCN guidelines recommending post-release monitoring and systematic data collection as central to the process. Since 1996, Habitat Ecologique et Liberté des Primates (HELP) has been releasing wild-born orphaned chimpanzees into natural habitat in the Conkouati-Douli National Park, Republic of Congo. HELP developed a post-release monitoring system as an integral component. We present activity budgets and diet of released chimpanzees, and compared them to those of wild chimpanzee, as primary indicators of successful release. Feeding, moving, and resting dominated activity budgets, reflecting the overall patterns in wild populations. Diet was diverse and dominated by fruit, and the released chimpanzees showed specialization on a smaller number of species, as in many wild communities. The high survival rates of the chimpanzees and overall success of the release program are attributed to careful planning and post-release support facilitated via the monitoring process. Systematic post-release data collection monitoring has confirmed that wild-born chimpanzees can adjust behaviorally and nutritionally to the wild. Survival statistics of the reintroduced chimpanzees—confirmed 56%, possible 88%— reflect the behavioral adaptability.2nd revision March 11, 2005An erratum to this article can be found at 相似文献
14.
Hideshi Ogawa Gen’ich Idani Jim Moore Lilian Pintea Adriana Hernandez-Aguilar 《International journal of primatology》2007,28(6):1397-1412
We conducted ecological studies of chimpanzees (Pan troglodytes) in the Ugalla area, western Tanzania. Ugalla is one of the driest habitats of chimpanzees and the Ugalla River is the eastern
boundary of chimpanzee distribution. Most of Ugalla is occupied by savanna woodlands dominated by deciduous trees of Brachystegia and Julbernardia. Chimpanzees tended not to make nests in riverine forests in plains, but in small patchy forests dominated by Monopetalanthus richardsiae and valley forests dominated by Julbernardia unijugata on slopes in mountainous areas. We estimated population density of chimpanzees to be 7–9 × 10−2 individuals/km2 based on nest censuses, suggesting that 2–3 × 102 individuals inhabited the 3352 km2 area of Ugalla. The size of the largest nest cluster (n=23) suggests that 1 unit group (community) comprised 30–35 individuals.
In the daytime, chimpanzees formed small feeding parties (mean 2.0 individuals), but larger ones in the evening (mean 4.8
individuals and 5.2 individuals based on fresh nest clusters). The pattern might reduce the predation risk from large nocturnal
carnivores such as lions and leopards. The sleeping sites may function as both a safe sleeping site and a meeting point for
chimpanzees with a huge home range that may have difficulty in finding other members of their unit group. 相似文献
15.
Four pine forests (6–10, 11–15, 16–20, and 31–40 year-old) located in the Cangshan Mountain and Erhai Lake National Reserve
and 7 pine forests (1–5, 6–10, 11–15, 16–20, 21–30, 31–40, and more than 50 year-old) located in the non-protective area near
the national reserve were selected. Three replications of each forest was set and a total of 33 sites were investigated. At
each site, we quantified 6 habitat variables (species richness, abundance, and percentage of grasses and shrubs coverage respectively
at the bottom layer of forests) within randomly determined 5 m × 5 m areas. One hundred cages were set in five lines at each
site to trap small mammals, whose species and numbers were recorded. Dominance of Dremomys pernyi and Callosciurus erythraeus in small mammal communities, time niche breadth, and time niche overlap between the two small mammals were calculated, respectively.
Step-wise regression was used to analyze the relationship between small mammals and habitat factors. Our results indicated
that D. pernyi occurred earlier than C. erythraeus in protective pine forests. D. pernyi was captured in 6–10 year-old forest initially, and C. erythraeus was captured in 16–20 year-old forest initially. D. pernyi and C. erythraeus were captured in the 31–40 and 21–30 year-old forests initially in the non-protective area, respectively. Populations of
D. pernyi and C. erythraeus in the 31–40 year-old protective forests were 3 and 3.75 times of those in the same-aged non-protective forests, respectively.
Shrubs significantly influenced the populations of the two small mammals. The population of D. pernyi was positively correlated with the density of shrubs; the population of C. allosciurus erythraeus was positively correlated with the coverage of shrubs, and negatively correlated with the coverage of grasses. D. remomys pernyi and C. allosciurus erythraeus were important for pine forests to scatter pine seeds. Human activities in the nonprotective pine forests decreased the vegetation
heterogeneity at the bottom layer of pine forests, postponed the occurrence of D. pernyi and C. erythraeus, and decreased the populations of the two small mammals.
__________
Translated from Zoological Research, 2006, 27(1): 29–33 [译自: 动物学 研究] 相似文献
16.
Yukimaru Sugiyama 《Primates; journal of primatology》1984,25(4):391-400
The population dynamics of a small group of wild chimpanzees at Bossou, Guinea, were studied during a 6.5-year period between
1976 and 1983. The natality rate (0.23 births/female/year) was higher and the interbirth interval (4.3–4.4 years/female) was
shorter than those of chimpanzees at East African study sites (the Gombe and Mahale National Parks). The infant mortality
for the first 3 years (0.06–0.18/year) was lower than those in East Africa. However, the population had remained almost stable
since 1967 (growth rate: 0.985/year). The increase in number by births was offset by the disappearance (perhaps emigration)
of adolescent chimpanzees. Adult males immigrated and disappeared (perhaps emigrated) but adult females rarely did. 相似文献
17.
This study examined the impact of wetland habitat loss and isolation on an insect–plant interaction, and the subsequent rate of recovery of the interaction following experimental habitat restoration. We compared herbivore colonisation rates and herbivory damage by ‘Batrachedra’ sp. (Lepidoptera: Coleophoridae) on experimentally placed potted Sporadanthus ferrugineus (Restionaceae) plants at increasing distances (up to 800 m) from an intact habitat (the source population). These tests showed that even a moderate degree of isolation (i.e. greater than 400 m) from the intact wetland habitat caused an almost complete collapse of the insect–plant interaction, at least in the short term. The number of eggs and larvae of colonising ‘Batrachedra’ sp., as well as average larval size and the proportion of S. ferrugineus stems damaged, all decreased logarithmically with increasing distance from the intact habitat, presumably due to dispersal limitation of the herbivore. Subsequently, to test whether the interaction can recover following habitat restoration, we surveyed herbivore colonisation rates and herbivory damage on naturally regenerated S. ferrugineus plants on experimentally restored ‘islands’ at increasing distances (up to 800 m) from an intact habitat. The rate of recovery of the interaction was surprisingly rapid (i.e. between 196 and 308 weeks). The degree of difference in the density of eggs and larvae, and in the proportion of stems damaged with increasing isolation from the intact wetland, gradually diminished over 196 weeks. After 308 weeks there was no significant difference in the insect–plant interaction between the intact wetland sites and any of the experimentally restored sites up to 800 m away. These results suggest that some insect–plant interactions can recover rapidly from habitat loss with restoration management.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
18.
Comparison of the complete mitochondrial DNA (mtDNA) of the high-Arctic ringed seal (Phoca hispida) and the sub-Arctic harbour (P. vitulina) and grey (Halichoerus grypus) seals shows that they are genetically equidistant from one another. We relate the evolutionary divergence of the three species
to expanding glaciation in the Arctic Basin and establish, in conjunction with mtDNA data, a standard reference for calibration
of recent divergence events among mammalian taxa. In the present study, we apply the “Phoca standard” to the dating of divergences within the hominid phylogenetic tree. After determining the relative rates of substitution
over all mitochondrial protein-coding genes in the different evolutionary lineages, we estimate that humans and chimpanzees
diverged from each other 6.1 Mya (95% confidence limits: 5.2–6.9 Mya). The corresponding lower-limit divergence between common
chimpanzee,Pan troglodytes, and pygmy chimpanzee,P. paniscus, occurred 3 (2.4–3.6) Mya, and the primary split within theP. troglodytes complex 1.6 (1.3–2.0) Mya. The analyses suggest that the split betweenGorilla andPan/Homo occurred 8.4 (7.3–9.4) Mya. They also suggest thatPongo (orangutan) and the lineage leading to gorillas, chimpanzees, and humans diverged 18.1 (16.5–19.6) Mya. The present analysis
is independent of the hominid paleontological record and inferential morphological interpretations and thus is a novel approach
to the lower-limit dating of recent divergences.
Correspondence to: U. Arnason 相似文献
19.
We report on the isolation and characterization of 11 microsatellite loci in the Sichuan snub-nosed monkey (Rhinopithecus roxellana) from AC-enriched genomic libraries. 20 microsatellite loci were screened from the libraries, of which 11 were polymorphic.
The number of observed alleles among 32 samples of snub-nosed monkey ranged from three to nine. The observed and expected
heterozygosity were 0.071–0.815 and 0.201–0.819, respectively. The high variability revealed in this study should be useful
tools for further study on social structure and population genetics of snub-nosed monkey in the future. 相似文献
20.
Fish respiration rates that are presumed to represent standard metabolic rates (SMR) may sometimes include an unspecified energy expenditure associated with activity and digestion. This situation may introduce a bias in bioenergetics models because standard metabolism, digestion, and activity may not be affected by the same environmental conditions. The aim of this study was to (1) develop a SMR model for juvenile yellow perch, Perca flavescens (Mitchill), that represent the minimum energy expenditure required to maintain life and (2) compare the results of this study with published perch metabolic rates and bioenergetics models. SMR was estimated for yellow perch over a range of body␣mass (4.4–24.7 g) and water temperature (12–20°C). The intercept of the relationship between fish respiration and swimming velocity obtained during forced swimming experiments was used to determine SMR. SMR estimated by the present study were comparable to values presented by two published studies on Eurasian perch, Perca fluviatilis L. However, estimated SMR were 4.1–20.9 times lower than values of a third respirometry study and predictions of bioenergetics models for perch. The present study suggests that published SMR models may sometimes include a significant fraction of energy expenditures (39.2–75.9%) associated with digestion and activity. This may complicate the implementation and the interpretation of fish bioenergetics models. The present study indicates that the intercept of respiration-velocity relationships and long-term respiration rates during starvation experiments may provide similar and reliable SMR values. 相似文献