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1.
芍药的访花昆虫和传粉昆虫 总被引:2,自引:0,他引:2
20 0 0~ 2 0 0 2年对内蒙古赤峰市高格斯台罕乌拉自然保护区内野生芍药 (PaeonialactifloraPall.)和内蒙古农校芍药园内栽培品种芍药的访花昆虫进行调查 ,经整理鉴定有 2 9种 ,自然保护区内芍药的访花昆虫种类有 1 7种 ,芍药园内的访花昆虫有 1 7种。根据传粉行为和数量的比较确定了自然保护区内主要传粉昆虫为丽斑芫菁、黄胫宽花天牛、黑胫宽花天牛、短毛斑金龟、饥星花金龟、白星花金龟和大淡脉隧蜂 ;芍药园内的主要传粉昆虫为意大利蜜蜂、棕边管食蚜蝇、长尾管食蚜蝇、大淡脉隧蜂、灰带管食蚜蝇和小淡脉隧蜂。 相似文献
2.
The Organization of Male and Female Labor in Foraging Societies: Implications for Early Paleoindian Archaeology 总被引:1,自引:0,他引:1
NICOLE M. WAGUESPACK 《American anthropologist》2005,107(4):666-676
I use cross-cultural ethnographic data to explore the relationship between male and female subsistence labor among hunter-gatherer populations by examining data regarding resource procurement, time allocation, and task differentiation between the sexes relative to dependence on hunted foods. The findings indicate that female foragers generally perform a variety of nonsubsistence collection activities and preferentially procure high-return resources in hunting-based economies. I develop ideas about predictable relationships concerning the amount of time female foragers expend on subsistence and technological tasks relative to the dietary contribution of meat. I then use ethnographic trends to evaluate archaeological assumptions regarding the sexual division of labor in prehistoric foraging contexts, focusing on the dichotomous views of Clovis labor organization. I argue that archaeological interpretations of prehistoric labor roles in hunting-based foraging societies are commonly polarized between stereotypical views of male and female subsistence behaviors. I develop an interpretation of Early Paleoindian labor organization, emphasizing female labor in the production of material goods and the procurement of low-risk plant and animal resources based on global economic trends among foragers. 相似文献
3.
Nikitopoulos Eleni Arnhem Eric van Hooff Jan A. R. A. M. Sterck Elisabeth H. M. 《International journal of primatology》2004,25(3):659-677
We investigated the function of copulation calls—vocalizations by females during mating—in captive groups of long-tailed macaques. We tested predictions of the contest-competition, sperm competition, synchronized orgasms, mate again, alpha-male notification and graded-signal hypotheses. We observed 371 copulations of 36 females wherein the presence or absence of a copulation call was clear. Females call equally often with different males and shortly after ejaculation. Copulation calls occurred equally with copulations with and without ejaculation. Calls did not incite disruptions of the mating. Following calls females mated again, more often than expected, with their mating partner. Both pregnant and fertile females uttered copulation calls. Two females conceived and mated mainly with the alpha male then. We conclude that copulation calls do not incite male contest competition for sexual access to females and that it is unlikely that calls synchronize male and female orgasms. Several hypotheses remain plausible, but not all predictions are borne out unequivocably. This alerts us to the possibility that the calls could have multiple beneficial effects; natural selection might strike a compromise among functions. Investigation of the mate again, sperm competition and alpha-male notification hypotheses, and of hypotheses not tested in our study concerning female breeding overlap and female-female agonism, is required. 相似文献
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柴胡大、小孢子发生及雌、雄配子体发育 总被引:6,自引:0,他引:6
以柴胡(Bupleurum chinense)为研究对象,运用石蜡切片技术对其大、小孢子发生及雌、雄配子体发育进行了研究。结果表明:柴胡花药具4个药室,花药壁由表皮、药室内壁、中层和绒毡层4层细胞构成,花药壁发育为双子叶型,腺质绒毡层。小孢子母细胞减数分裂的胞质分裂为同时型,产生正四面体型小孢子。成熟花粉三细胞型。胚珠倒生型,单珠被,薄珠心。大孢子母细胞常为一个雌性孢原直接发育而成,大孢子四分体呈线型或T型排列,多数情况为合点端一个大孢子分化为功能大孢子,由功能大孢子发育为蓼型成熟胚囊。在胚囊发育过程中,珠被内表皮细胞特化成珠被绒毡层。同一朵花中,雄蕊先熟,记录了花蕾大小及雌、雄配子体发育的对应关系。 相似文献
6.
Animals collecting patchily distributed resources are faced with complex multi-location routing problems. Rather than comparing all possible routes, they often find reasonably short solutions by simply moving to the nearest unvisited resources when foraging. Here, we report the travel optimization performance of bumble-bees (Bombus terrestris) foraging in a flight cage containing six artificial flowers arranged such that movements between nearest-neighbour locations would lead to a long suboptimal route. After extensive training (80 foraging bouts and at least 640 flower visits), bees reduced their flight distances and prioritized shortest possible routes, while almost never following nearest-neighbour solutions. We discuss possible strategies used during the establishment of stable multi-location routes (or traplines), and how these could allow bees and other animals to solve complex routing problems through experience, without necessarily requiring a sophisticated cognitive representation of space. 相似文献
7.
绞股蓝雌雄种群觅源行为和繁殖对策比较 总被引:6,自引:0,他引:6
绞股蓝(Gynostemma pentaphyllum)雌雄异株,种群性比偏雄。作者利用比较生态学方法,从行为生态学角度探讨相同生境中绞股蓝雌雄种群的觅源行为和繁殖对策,得到如下初步结果和结论:(1)绞股蓝雄性种群的主枝生物量比显著大于雌性种群,这意味着雄性种群的营养繁殖投资显著增加,而两性种群在其它结构中的生物量分配无显著差异;(2)雌性种群的叶面积比和单位叶面积比雄性种群显著增加,这与两性种群 相似文献
8.
对可育系和雄性不育系万寿菊的大、小孢子发生及雌、雄配子体发育过程进行了系统地比较观察。结果表明:可育系和不育系万寿菊雌蕊的发育基本相同,二者的雌蕊为二心皮一室,每室1胚珠,单珠被,薄珠心,倒生型胚珠。大孢子母细胞经减数分裂形成线形排列的4个大孢子,合点端为功能大孢子。胚囊发育类型为蓼型。可育系小孢子母细胞经过减数分裂形成四面体形的四分体,成熟花粉是二细胞型,表面有刺。其花药为四室,药壁发育属双子叶型,腺质绒毡层。雄性不育系万寿菊特化小花在花芽分化时即没有产生雄蕊原基,因而不具雄蕊结构,为结构型雄性不育。 相似文献
9.
Mewa Singh H. N. Kumara M. Ananda Kumar Mridula Singh Matthew Cooper 《International journal of primatology》2006,27(2):515-528
In bonnet macaques, males usually disperse between groups and females remain philopatric, but researchers have reported female
transfer. We report a rare case of male influx during the mating season in our bonnet macaque study group in the Anaimalai
Hills. The density of bonnet macaques in the study region was unusually high. The study group had a single, crippled adult
male with a long tenure and 5 adult females. During the mating season, adult females approached and mated with outgroup males,
and then several males entered the group. The adult male left the group without any resistance. The incoming males mated with
3 receptive females, forcibly mated with 2 lactating females, and attacked and killed 2 infants. During the influx, 2 outgroup
females joined the group. The data suggest that male influxes provide an opportunity for infanticide and female transfer,
which can have important fitness consequences even in species in which they rarely occur. 相似文献
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李利平;刘海燕;陈发菊 《植物研究》2013,33(2):145-148
采用石蜡切片法对黄金树大、小孢子发生及雌、雄配子体发育的过程进行了详细的细胞学观察。结果表明:黄金树子房两室,中轴胎座,胚珠多数,倒生。单珠被,薄珠心,孢原细胞直接发育成大孢子母细胞。单孢原蓼型胚囊。黄金树雄蕊五枚,三枚退化,二枚可育。花药二室,腺质绒毡层,小孢子四分体排列方式为正四面体型,成熟花粉粒为四合花粉。 相似文献
12.
大叶补血草的大、小孢子发生与雌、雄配子体的发育 总被引:1,自引:0,他引:1
系统地报道了大叶补血草(Limonium gmelinii (Willd.) Kuntze)的大、小孢子发生和雌、雄配子体的形成发育过程。主要结果如下:(1)小孢子母细胞减数分裂过程中的胞质分裂为同时型,四分孢子多为正四面体形, 也有少数为左右对称形;(2)成熟花粉为三细胞型,具3个萌发孔;(3)花药壁由5层细胞组成,最外层为表皮,其内分别为药室内壁、中层、绒毡层,绒毡层为变形型,花药壁的发育属于基本型;(4)大叶补血草的雌蕊由5心皮合生,子房1室,基生胎座,胚珠1个,拳卷型,双珠被,厚珠心;(5)孢原细胞发生于珠心表皮下,经一次平周分裂,形成造孢细胞,由造孢细胞直接发育成大孢子母细胞,大孢子母细胞减数分裂形成4个大孢子呈直线排列,合点端大孢子具功能,属于典型的蓼型胚囊发育。 相似文献
13.
Pascale Sicotte Julie A. Teichroeb Tania L. Saj 《International journal of primatology》2007,28(3):627-636
Male Colobus vellerosus are the main participants in intergroup encounters, and lead incursions in neighboring groups during which they attack infants.
Extragroup copulations, all-male groups, and male takeover occur in the species. Here, we provide additional information on
behaviors associated with male reproductive competition in Colobus vellerosus. We examined 1 resident male loud calling and participation in intergroup encounters in relation to a takeover. We also report
a second case of takeover that led to the death of the former resident male and the death of 2 male infants, presumably as
a result of aggression from the all-male group. The new resident male wounded the third infant of the group, which apparently
died after its mother abandoned it. During the period characterized by the attacks on the infant and after its disappearance,
females initiated and participated in loud call bouts with the new resident male. We examine the possible functions of female
loud calling, and suggest that in this context, it might force the resident male to call along to indicate his presence. 相似文献
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PEDRO JORDANO 《Biological journal of the Linnean Society. Linnean Society of London》1993,50(1):65-84
This study describes the reproductive biology of Prunus mahaleb, a rosaceous treelet, in a southeastern Spanish population. The species is gynodioecious with 55.4% of the plants being male-fertile and 44.6% presenting non-functional, shrunken anthers with no pollen, and behaving as functional females. Individual trees produced the same flower morph in four consecutive study years. Fruit set in bagged inflorescences was absent in male-sterile trees and was very reduced in male-fertiles. Open-pollinated flowers of male-fertiles showed greater fruit set (x?= 29.1%) than male-steriles (x?= 25.3%). Average fruit set in three experimental treatments (control, selfed, and crossed) were 29.05%, 41.9% and 38.6%, respectively, for male-fertile trees; those for male-steriles were 25.3%, 0% and 39.2%, respectively. Seeds from male-sterile plants were heavier (71.33 mg) than those of male-fertile plants (66.05 mg) but did not differ in germination ability. Male-fertile and male-sterile trees differ significantly in average nectar concentration (73.5% and 55.9%, respectively) and nectar volume secreted/flower and day (0.142 μl and 0.171 μl, respectively). A total of 41 species of insect flower visitors were recorded. Calliphorid and tachinid flies (41.97% of total visits), and andrenid bees (30.30%), were the most frequent visitors. The diversity of insect visitors was greater in male-fertile trees. Bees and flies accounted for 50.5% and 49.5%, respectively of total visits to male-fertile trees. Flies were far more frequent than bees at male-sterile flowers (76.9% and 23.1%, respectively). Male-sterile trees received higher average visitation (47 insects/census) than male-fertile trees (32 insects/census). Individual trees. showed a relative constancy of the fecundity rankings between years. Fruit production was significantly higher in male-sterile trees, with a four-year average of 6558 fruits, in contrast with male-fertile trees which yielded 4670 fruits. This 1.77-fold difference in favour of male-sterile trees over malefertiles was not compensated by the greater fruit set of the latter. This is attributable to the lower outcrossing rate of male-fertiles, estimated as 52.68% from seed mass data. In addition, greater seed mass of female progeny, and higher visitation rate by insects might explain the maintenance of this polymorphism. These results have far-reaching implications for the demography and seed-dispersal ecology of this endozoochorus species. 相似文献
16.
Sterck and colleagues (Behaviour 134:749–774, 1997) focused attention on the evolutionary ecology of female social relationships within and between groups and proposed a model
that distinguishes 4 categories of female relationships, which correspond to particular types of intra- and intergroup competition.
They emphasized literature on haplorhines in their model because of numerous, detailed studies conducted on a range of species
in the wild; in contrast, strepsirrhines such as the lemuroids are poorly represented. We evaluate more closely their classification
of lemuroids as Dispersal-Egalitarian using a greater number of species of Lemur, Eulemur, Varecia, Hapalemur, Indri, and Propithecus. For the focal species we found that female philopatry occurs rarely, agonistic rates are relatively low, female dominance
hierarchies are not stable and do not exist year-round, and intra- and intergroup female-female competition is infrequent.
Therefore, our results support the suggestion that a majority of lemuroid taxa we surveyed correspond to the Dispersal-Egalitarian
category with 2 probable exceptions: Lemur catta and Propithecus edwardsi. Because female Lemur catta are philopatric, have year-round dominance hierarchies with female matrilines, exhibit the highest rates of agonism in studied
lemuroids, and have frequent intra- and intergroup female-female competition, it would seem that they more closely correspond
to the category Resident-Nepotistic. However, maternal Lemur catta rarely support their offspring in agonistic contests and matrilineal rank is not inherited, which leads us to state that
the species does not fit into any existing category that explains the nature of female social relationships. The relationships
of female Propithecus edwardsi are also a challenge to categorize under the current model because some of their characteristics —typical female dispersal
and low agonistic rates— fall into the Dispersal-Egalitarian category, yet other behaviors —intense targeted aggression and
stable and year-round female dominance hierarchies— do not. 相似文献
17.
Abstract Field experiments on an orchid, Platanthera mandarinorum ssp. hachijoensis , were carried out to investigate the effects of variations in spur (nectary) length and pollinator activity on reproductive success (RS) of individual plants. Experiments comprised two kinds of treatments: spur shortening and bagging to restrict pollinator activity. Plants with a natural spur lengths range show nearly equal RS, whereas plants with shortened spurs had decreased RS proportional to spur length reduction. Pollinaria attachment (a measure of male RS) to the pollinators seems to demand stricter morphological correspondence than pollen receipt (female RS). Decrease of male and female RSs in spur-treatments was smaller in the case of high pollinator activity than low pollinator activity. Results of the bagging experiments indicated that female RS was greater than male RS in cases of high pollen carryover. These facts suggest that (1) fecundity selection operates more intensely on both male and female functions in the case of low pollinator activity and more intensely on the male function in the case of high pollen carryover, and (2) individuals with different spur lengths in natural populations have nearly equal probabilities of RS after excluding the extreme variants through the reduction of male RS. 相似文献
18.
Foraging dynamics of bumble bees: correlates of movements within and between plant species 总被引:7,自引:3,他引:7
What rules determine whether bumble bees continue exploitingplants of the species just visited or switch to another species?To tackle this question, we recorded handling times and flighttimes from bees foraging in a natural meadow containing fiveplant species. Inter- and intra-specific plant distances werequantified. The bee-subjective colors of the five species weredetermined; two of these species had similar colors and structures,while three species were distinct from all others. The followingrules were identified: (1) The decision to switch species wascorrelated with previous flower handling time, which we assumeis a function of the reward amount received at the flower. Aftershort handling times, the probability of switching to anotherspecies increased, whereas it decreased after long handlingtimes. This difference became even greater if the bee had hada run of several short or several long handling times. (2) Constantflights (those between flowers of the same species) and transitionflights (those between flowers of different species) followedstereotyped temporal patterns independent of the distances betweenflowers. Constant flights within five plant species consistentlyhad median durations of about 2 seconds, whereas median transitiontimes between species took 36 seconds. (3) This temporalrule broke down, however, if the flowers of two species hadsimilar colors, in which case transition flights had equal dynamicsas constant flights. (4) Bees switched more frequently fromrare than from common species but even more frequently betweensimilar species. We conclude that the bees' choices were determinedby a set of rules that guided them to stay with the currentplant species as long as flowers were rewarding and availablewithin close distance but to switch to another species if flowersoffered low rewards or were not encountered at close range 相似文献
19.
Mating in the scaly cricket Ornebius aperta often includes the transfer of many spermatophores to individual females during extended copulatory interactions. We manipulated male condition in staged matings to determine whether this could explain variation in the number of repeated copulations seen across pairs. Males on a high nutrient diet were in good condition, were more likely to mate repeatedly, and transferred more spermatophores on average than low-diet males (in poor condition). High-diet males were more likely to produce a vibratory signal that increased female receptivity to repeated mating attempts. Courtship and copulatory interactions were always terminated by females, and in every case males had already formed a spermatophore when deserted by females. We conclude that variation in male repeated mating success may be due to female choice rather than an inability or unwillingness of low-diet males to produce spermatophores. 相似文献
20.
Examining the distribution of female preference and attractive male secondary sexual characters in closely related species can help evaluate the various models for the evolution of female preference. We examined whether orange coloration in males was attractive to females of Poecilia picta, a species in the same subgenus as the guppy, P. reticulata. Females did not respond differently to males with or without a conspicuous orange stripe on the dorsum of the tail, a characteristic ornamentation of the male of this species. This lack of preference in a taxon that possesses a conspicuous, secondary sexual character directly contradicts the predictions of the sensory exploitation hypothesis for the evolution of female preference, but may support a model of antagonistic sexual selection proposed by Rice (1996). 相似文献