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1.
The stumptail macaque species Macaca thibetana and Macaca arctoides replace one another from north to south in subtropical and tropical China. These species differ in external and cranial characters. Neonatal pelage color is pale grayish-brown in M. thibetana and whitish in M. arctoides. In adults, ventral pelage is whitish in M. thibetana and brown in M. arctoides. The forehead and cheeks are thickly furred in adult M. thibetana and bald in M. arctoides. Facial skin color typically is sexually dimorphic in M. thibetana—buffy in males and reddish in females—and monomorphic in M. arctoides—reddish in both sexes. Head and body length, weight, relative tail length, and relative ear length all tend to average greater in M. thibetana than in M. arctoides. Skull length, rostral-postrostral ratio, and relative canine length in males average greater in M. thibetana. than in M. arctoides; relative zygomatic breadth and relative bimalar breadth average greater in M. arctoides than in M. thibetana. Reproductive anatomy in both sexes is strikingly divergent in these two species. Although these species are adapted to different climatic zones, many aspects of their natural history are generally similar, as far as is now known. One apparent behavioral difference is that M. thibetana usually sleeps in caves or rocky crevices, while M. arctoides usually sleeps in trees.  相似文献   

2.
Natasha Newsome 《Grana》2017,56(5):377-385
This study aimed to determine whether or not a seasonal, or even monthly, pattern of pollen accumulation could be found in surface soil. Three mature woodlands in the English Midlands were selected and soil samples were taken from the same area, each month, for 12 months. Pollen types were recorded and compared across the woodlands. Pollen condition was assessed for seasonal differences in Bannam’s woodland. Two of the woodlands (Windmill Naps and Wirehill) had pollen assemblages that were dominated heavily by Quercus pollen but the third (Bannam’s) was more balanced. Each pollen type found was present in almost every month and winter was, for some types, a time of increased pollen. No clear, consistent patterns were visible in the results across the woodlands or for each pollen type. Although some pollen types showed an increase in levels during their flowering season, this was only consistent across all three woodlands for grasses (Poaceae). The condition of the pollen grains remained similar across the 12 months with a small (up to 12%) increase in fresh pollen in May. This study concludes that for damp woodland soil in the English Midlands, a clear, seasonal or monthly pattern cannot be determined.  相似文献   

3.
4.
Benayahu  Y. 《Hydrobiologia》1991,(1):125-130
This work on Red Sea alcyonaceans describes the reproductive patterns of 21 xeniid species. Gonochorism is the commonest sexual mode but simultaneous hermaphroditism was recorded in 4 species and brooding of planulae was observed in 15 species. The reproductive patterns of Xenia umbellata and Heteroxenia fuscescens were examined. X. umbellata exhibits seasonal spermatogenesis, continuous oogenesis and a 7 month period of planulation each year. H. fuscescens has continuous gametogenesis, and planulation occurs throughout the year, lacking any lunar pattern. The prolonged breeding season of H. fuscescens reflects intrapopulation asynchrony in larval development and subsequent maturation. Xeniids possess structurally similar gonads, but adopt diverse reproductive and developmental pathways.  相似文献   

5.
The length of the baculum (os penis) was measured in 74 adult males representing 46 primate species. These data, and a review of previously published measurements, indicate that variation in baculum length among primates is related to taxonomic and behavioral differences. Thus, many New World monkeys have shorter bacula, relative to body weight, than Old World monkeys. The baculum is shorter in colobine monkeys than in cercopithecines. Among the great apes, reduction of the baculum is more pronounced in Pan and Gorilla than in Pongo. Very long bacula are found in some nocturnal prosimians (eg, Lorisidae) and also in Macaca arctoides. A comparison of baculum length relative to body weight was made in 34 species for which detailed information on copulatory behavi or was available. The presence of an elongated baculum was shown to correlate with copulatory patterns involving prolonged intromission and/or the maintenance of intromission during the postejaculatory interval (eg, Galago crassicaudatus, Loris tardigradus, M, arctoides). The evolutionary significance of these observations is discussed and it is suggeted that similar copulatory patterns may occur in species with elongated bacula (eg, Daubentonia, Perodicticus) for which behavioral data are lacking at present. The same hypothesis also applies to an extinct adapid primate which possessed a very large baculum.  相似文献   

6.
The seasonal occurrence of the bont tickAmblyomma hebraeum was recorded over 2 years on 20 Brahman cattle held in a 240-ha paddock at Mbizi in southeastern Zimbabwe. The cattle were infested with all life cycle stages throughout the study period, and no clearly defined seasonal patterns were recorded. Males remained attached for up to about 6 months, and consequently accumulated on the cattle and outnumbered females considerably. The cattle did not acquire resistance toA. hebraeum and the abundance of the adults increased steadily over the 2 years of sampling. The occurrence of adults and nymphs on hosts appeared to be largely independent of weather, and these stages were active over the entire range of temperature and relative humidity recorded during the study period. It was concluded that unfed adults and nymphs are able to engage in host-seeking irrespective of weather conditions as they do not await hosts on the vegetation but emerge from protected microhabitats in response to specific stimuli from hosts, notably, carbon dioxide and the aggregation-attachment pheromone emitted by attached males. This behavior may explain the reported absence of a consistent pattern of seasonal occurrence ofA. hebraeum at different locations in southeastern Africa.  相似文献   

7.
Jouffroy (Bulletin du Muséum National d'Histoire Naturelle. Série 2 31:209–216, 1959) described Macaca speciosa subfossilis on the basis of her study of the external anatomy of a nearly complete cranium (PV F1; Muséum national d’Histoire naturelle, Paris) found in the Late Pleistocene cave deposits, Thung-Lang, northern Vietnam. Whereas Jouffroy (Bulletin du Muséum National d'Histoire Naturelle. Série 2 31:209–216, 1959) considered it to belong to an ancestor of Macaca arctoides or M. thibetana, Fooden (Journal of Human Evolution 19:607–686, 1990) reexamined the facial anatomy and assigned it to the extant species M. arctoides. We used computed tomography images to reevaluate the phylogenetic position of Macaca speciosa subfossilis by comparing the external and internal features of PV F1 with those of the crania of the extant macaque species. PV F1 shows a lower degree of preorbital concavity than Macaca arctoides, M. assamensis, and M. thibetana, but shares an anteriorly directed malar as seen in the crania of the two former species. The size of the molars of PV F1 falls within a range such that the cranium may be assigned to any of the five species of Macaca arctoides, M. assamensis, M. thibetana, M. mulatta, and M. nemestrina. An analysis of the internal structure of the cranium reveals that only PV F1 and the cranium of Macaca arctoides have a pear-shaped nasal cavity expanding laterally at both the anterior and posterior regions. Such a feature is probably a derived condition in the macaque lineage, suggesting a close relationship between Macaca speciosa subfossilis and M. arctoides. This finding supports the paleobiological scenario that the members of the lineage of Macaca arctoides diverged from the other members of Asian macaques and became distributed in northern Vietnam as early as the Late Pleistocene.  相似文献   

8.
Summary A fauna of small invertebrates in a perennial algal turf habitat showed marked seasonal fluctuations in abundance. These were characterised by a summer (December) peak in the abundance of gammarid amphipods and an autumn (April) peak in polychaete densities. Invertebrate abundance was lowest during the period February–March which coincided with an influx of very high densities of juveniles (0+ year class) of the sparid fish Chrysophrys auratus. Both juvenile C. auratus and also the mullid Upeneichthys porosus achieved their highest densities over coralline turf areas and fed on the associated invertebrates. Gammarid amphipods constituted the main food items of each species. All these observations suggested a key role of fish predators in determining the observed seasonal patterns of invertebrate abundance.This hypothesis was investigated by the use of replicated fish exclusion shields and cages which excluded both species from the algal turf and also permitted an assessment of Upeneichthys porosus feeding in the absence of Chrysophrys auratus. The experiment ran from November until June and covered the period of invertebrate and fish abundance changes. Little evidence of a fish predation effect on either the densities of or the timing of abundance peaks of the invertebrate fauna was detected. Sediment analysis of the cage and control experimental sites revealed no evidence of a cage effect on the microhabitat. It is suggested that seasonal changes in the abundance of invertebrates occurs independently of the high densities of predatory fish recorded in this habitat.  相似文献   

9.
Tropical kelp populations are rare and anomalous relicts of shallow‐water populations that existed during glacial periods of cooler oceanographic climate. The endemic Brazilian tropical kelp, Laminaria abyssalis Joly and Oliveira Filho, occurred at depths below 40 m. The seasonal variations in biological aspects of L. abyssalis sporophyte populations and local variations in seawater nutrients and temperature were evaluated. A population was sampled four times between the austral spring of 2005 to winter 2006. Seasonal variations in the population structure and in the tissue content of nitrogen (N), carbohydrate and pigments were observed. Higher density (6.3 individuals m?2), biomass (7.3 kg m?2) and blade area (13 221 cm2) were observed in summer, while the highest percentage of tissue total N (1.6%), carbohydrates (32.9%) and photosynthetic pigments (chlorophyll a = 1.9% and chlorophyll c = 0.4%) were observed in spring. The highest surface area of fertile tissue in L. abyssalis sporophytes (2.36%) was recorded in winter, indicating winter as the season when more investments are made in reproduction. The highest concentrations of total N (6.3 μM) and phosphate (0.6 μM) in seawater were observed in spring and summer, respectively. Seawater temperatures lower than 20°C, which are characteristic of upwelling waters, occurred every month and were most frequent in spring and summer. We show that L. abyssalis invests more in growth in spring and summer and reaches the greatest thallus size and population density in summer. The lower abundance during winter may be related to the lower frequency of temperatures below 20°C and the local seasonal storms that cause turnover of rhodoliths, the main substrate for L. abyssalis.  相似文献   

10.
2014年4—11月,选择黄河入海口北部滨岸高潮滩的碱蓬湿地为研究对象,基于野外原位氮输入模拟试验,研究了不同氮输入梯度下(N0,无氮输入;N1,低氮输入;N2,中氮输入;N3,高氮输入)碱蓬不同器官生物量以及氮累积与分配特征的差异。结果表明,尽管不同氮输入处理并未改变碱蓬地上生物量的季节变化模式,但在不同程度上均促进了地上生物量的增长(平均增幅为19.71%—62.29%)且整体表现为N3N2N1N0;不同氮输入处理亦延长了碱蓬的生长高峰期,N1、N2和N3处理下地上生物量达到最大值的时间相对于N0处理推迟20 d左右。与地上生物量不同,不同氮输入处理改变了地下生物量的季节变化模式,特别是N2和N3处理均对生长初期的地下生物量产生了明显促进作用,且其初期地下生物量达到较高值的时间相对于N1和N0处理提前20—50d。不同氮输入处理下的枯落物量在产生初期和中期均增幅不大,末期则骤然增加且整体表现为N3N2N1N0。不同氮输入处理下碱蓬各器官的全氮(TN)含量总体上均表现为叶茎根,叶是氮的主要累积器官。尽管不同氮输入处理并未改变碱蓬不同器官的氮累积与分配格局以及地上与地下之间的养分供给关系,但其为适应不同养分条件而调整自身养分供给与分配的特性在N2处理下表现的尤为明显。研究发现,N2处理下碱蓬种子的发育时间相对于N0、N1和N3处理可能会提前约1个月,原因可能与N2氮输入水平可显著影响碱蓬体内的碳分配比以及碱蓬对适量氮养分输入环境的特殊适应对策有关。随着黄河口新生湿地氮养分供给的不断增加,当未来碱蓬湿地氮养分状况达到较高水平(特别是中等水平)时,其生物量、生长节律(特别是种子发育时间)以及不同器官氮累积与分配状况可能将发生明显改变。  相似文献   

11.
A survey of airborne yeasts in Amritsar has been carried out by the petri plate exposure method for a period of one year. A total of 14 yeasts species appeared on the plates. Candida was the commonest yeast representing 43.1% of the total colony count followed by Rhodotorula and Torulopsis. There was a seasonal variation in the concentration of the yeasts in the atmosphere. Maximal numbers were recorded in October and minima during January–February.  相似文献   

12.
The composition, species richness and diversity of a coastal fish assemblage from the Kalpakkam coast of south‐east India are described along with temporal distribution patterns related to seasonal fluctuations in dissolved oxygen, salinity, pH, chlorophyll‐a, phytoplankton and zooplankton species richness and density. A total of 244 fish species belonging to 21 orders, 87 families and 163 genera were recorded. The fish assemblage was dominated by reef‐associated species, followed by demersal species. The majority of the species (63%) are widely distributed in the western Indo‐Pacific as well as in the central Indo‐Pacific. Jaccard's coefficient analysis showed three distinct seasonal patterns of fish occurrence: pre‐monsoon (PrM), monsoon (M) and post‐monsoon (PoM). The maximum number of species was during the PrM period, followed by the PoM and M periods. Species occurrence analysis showed Sardinella longiceps to be dominant during PrM and M periods, Leiognathus dussumieri during the M period and Secutor insidiator and Secutor ruconius during the M and PoM periods. Canonical correspondence analysis indicated that salinity and rainfall were the two most influential environmental factors strongly correlated with temporal variation in the fish assemblage. The physico‐chemical conditions, in combination with factors such as greater food availability and shelter, might control the seasonal local distribution of the ichthyofauna in these Indian coastal waters.  相似文献   

13.
Fig wasps associated with Ficus glaberrima were investigated in Xishuangbanna, China. A total of 97 figs from the same sample tree were collected over a period of three years, and 5171 fig wasps were recorded. Our results showed that Eupristina sp. progeny was not correlated with seeds in the three years. D. bizarrea only negatively affected Eupristina sp. and there was no obvious negative effect of D. bizarrea on seeds. The colonization rate of Eupristina sp. in December 2006 (dry season) was highest, while the colonization rate of D. bizarrea in August 2007 (rainy season) was highest. The colonization rates of Eupristina sp. and D. bizarrea were almost equal in December 2006 and July 2008 (rainy season). The number of Eupristina sp. progeny per fig during the colder month (December 2006) was significantly higher than during the warmer month (August 2007; July 2008) (LSD: P<0.05). There was no significant difference in the number of D. bizarrea progeny during three years. Eupristina sp., D. bizarrea, Sycoscapter sp., and Philotrypesis sp. occurred consistently as the most common fig wasps every year. This result suggested that some fig wasps showed a certain degree of season recurrence or specificity, but that the composition of fig wasps was not conspicuously influenced by the seasonal factor.  相似文献   

14.
Changes in pinosylvin concentration and distribution across the sapwood/heartwood boundary were studied on Scots pine (Pinus sylvestris L.) tree stems to detect seasonal activity in heartwood formation. Pinosylvin concentrations were measured with FT-(NIR) Raman spectroscopy for a total of 96 trees equally distributed on 16 different sampling occasions. In another experiment, cores were sampled every month from six individual Scots pine trees from June to October and analysed for pinosylvin. There was a great between-tree variation in concentration and spatial distribution of pinosylvin. No seasonal trend in the distribution pattern or concentration of pinosylvin was found. Therefore, the results indicate that there is no specific period during the year when heartwood is formed. Received: 12 February 1998 / Accepted: 3 May 1999  相似文献   

15.
Stump-tailed macaques (Macaca arctoides) exhibit significant intraspecific variation in pelage color. Based on their pelage color and geographical distribution, they are classified into 2 subspecies: northern bright brown Macaca arctoides arctoides and southern black Macaca arctoides melanota. However, studies on the natural population are extremely scarce, and researchers have occasionally questioned the subspecific classification. We quantitatively examined pelage color variation of Macaca arctoides in 3 free-ranging populations in Thailand. Pelage color difference between populations is significant. The population distributed south of the Isthmus of Kra showed wide intrapopulational variation, including bright brown, dark brown, and completely black, whereas the northern populations primarily had dark brown hairs. Thus, we conclude that one cannot classify the color variants into subspecies. Further, we hypothesize that the distinctive polymorphism in southern Thailand resulted from geographical isolation caused by the Pleistocene eustatic fluctuations and subsequent recovery of land connection and subsequent gene flow.  相似文献   

16.
This paper presents copulatory data gathered on a free-ranging population of stumptail macaques (Macaca arctoides) in Mexico. The study found evidence for seasonal clumping of matings, with the peak in the month of February, and that matings are more common in the afternoon, when measuring diurnal changes. It also found that males require an average of one and a half mounts before ejaculating, and mating among females is distributed unequally, when the measurement is between those females that mated. Furthermore, male dominance rank and male-female affiliation are both positively correlated with mating frequency. Variations between this study and captive studies are minimal. The variances that do occur may be explained by differences in the research settings or the individual differences in the subjects' behavior across studies.  相似文献   

17.
A five-year (1994–1999) continuous survey of aeromycoflora had been carried out in an agricultural farm at a suburban area of Greater Calcutta. The sampling was carried out with Burkard volumetric spore trap placed 0.5?meter above the ground level at the centre in a small plot in a rice field. A total of 26 fungal spore types were identified microscopically. The most abundant types were Basidiospores (21.85–5.59%) followed by Cladosporium, Periconia, Nigrospora, Aspergilli group, Ascospores. The seasonal periodicity of the major dominant types had maxima in autumn, during the month of October. This coincided with the harvesting period of the rice crop during rainy season. In Petri plate exposure of nutrient media, different species of aspergilli group, Alternaria, Cladosporium, Curvularia, Nigrospora, and other taxa were identified. The diurnal periodicities recorded for different types were classified into night-time, post dawn, middle day and double maxima (showing two peaks in a day) patterns. In general, no significant correlation between the total air spora and the meteorological parameters could be established. It is evident that the local cropping practices may have some regulating role on spore concentration in the air of the study area.  相似文献   

18.
Reproductive seasonality was examined in an equatorial population of free-living spotted hyaenas (Crocuta crocuta) in Kenya. The study population was observed continuously for 10 years, during which time the dates of all births, conceptions, weanings, and cub deaths were recorded. Local prey abundance was estimated two to four times per month, and rainfall was recorded daily throughout the study period. Births occurred during every month of the year, but a distinct trough in births occurred from February to May. This trough occurred approximately one gestation period after the phase of the annual cycle during which prey animals were least abundant in the home range of the hyaenas, and conceptions occurred most frequently when food abundance was greatest. Neither rainfall nor cub mortality were correlated with births or conceptions. Thus, although spotted hyaenas are capable of breeding throughout the year, they exhibit a moderate degree of seasonality that most likely reflects responses to seasonal variation in energy availability.  相似文献   

19.
Form and function of a specific kind of biting were studied in a captive group of stumptailed macaques (Macaca arctoides) composed of 1 adult male and 10 females. Behavior patterns were recorded with all occurrence and scan sampling techniques. Formal biting consisted of slowly gripping with teeth a part of the body of an apparently willing partner, most often the forearms, lips, or eyebrows. It may occur either following an agonistic interaction or outside the context of aggression. Such biting was directed from dominants towards subordinates, and appeared especially frequently between individuals having frequent agonistic interactions. It is concluded that this behavior represents a ritualized interaction expressing formal dominance between partners.  相似文献   

20.
The epibenthic encrusting fauna of 2 creeks of the Caeté mangrove estuary, northern Brazil, was studied over a 13 month period using collectors fixed at 2.5 and 3.5 m above the creek bottom and in which upper and lower sides of ceramic and wooden panels were used as settlement substrates. The number of individuals of the most abundant organisms (barnacles, oysters and mussels) settling per panel was determined each month, for each substrate type, panel orientation and height above creek bottom. The barnacle, Fistulobalanus citerosum has a peak settlement period during the wet season whereas both peaks in the numbers of settlers of the oyster Crassostrea rhizophorae were recorded during the dry season and such discrete temporal patterns in settlement have also been observed for barnacles and oysters in other mangroves and estuaries. In contrast to other studies, settlement of the mussel Mytella falcata was generally low during the study period and may be related to over-exploitation of stocks in the region. Overall, settler density was usually greater on the underside of ceramic panels close to the creek bottom, similar to results of other studies of epibenthic settlement in diverse habitats.  相似文献   

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