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1.
Karyotypes and morphology of three species with close relations toC. riihimakiensis Wülker 1971 are described from material of Tuva and Altai in Siberia. Only one of them could be reared to the male adult and was namedC. tuvanicus n.sp.  相似文献   

2.
Pair-living evolved several times independently in the primate lineage and most likely for more than one reason. Currently, there are 7 hypotheses regarding the evolution of pair-living in primates. They may explain several but not all cases. I investigated the applicability of the explanations to fork-marked lemurs Phaner furcifer. I used information from a long-term study on 8 fork-marked lemur families in Kirindy Forest to evaluate the hypotheses. Fork-marked lemurs live in uniform dispersed pairs, which share and defend a territory but spend three-quarters of their activity time apart from each other. Unconditional female dominance and lack of permanent close association between pair-partners disqualify most hypotheses. Lack of male parental care and long travel distances in small home ranges disqualify other explanations. I conclude that there is no support a priori for any current pair-living hypothesis and that the newly formulated intersexual-feeding-competition hypothesis best explains the evolution of pair-living in fork-marked lemurs. Accordingly, female range exclusivity evolved first as a consequence of intense feeding competition. Subsequently, indirect feeding competition drove females to accept a single male to share their territory as a defense against feeding competition from males whose ranges unsystematically overlap those of several females. This situation led to pair-living because formation of dispersed one-male-multifemale-units was too costly for males in terms of reduced foraging efficiency.  相似文献   

3.
Germinating barley grown on an artificial medium was exposed to75Se-selenite for 8 d. Then the leaves were homogenized and proteins were separated by means of Sephadex G-150 filtration, followed by DEAE-Sepharose chromatography. Each fraction collected was assayed for total protein, radioactivity, and peroxidase activity. In barley leaves, three protein peaks (peaks no. I, II, and III) with peroxidase activity could be separated by Sephadex G 150 filtration. Each fraction was then further separated on DEAE-Sepharose chromatography. Thus, peaks I and II were resolved by DEAE-Sepharose into one major and two minor peaks of radioactivity. However, only the major peak showed peroxidase activity. Peak III was resolved from the gel filtration on the DEAE-sepharose into one major and four minor peaks of radioactivity. The major and three of the minor radioactivity peaks contained peroxidase activity. The protein fractions were separated by polyacrylamide gel electrophoresis. The molecular weights of separated proteins were estimated by means of molecular markers, and75Se radioactivity was evaluated by autoradiography. Thus, gel filtration peak I contained four bands with mol wts of 128, 116, 100, and 89 kDa. Of these, the 89 kDa protein contained selenium. Peak II contained three protein bands, with mol wts 79.4, 59.6, and 59.9. The 59.6 band was a selenoprotein. Peak III contained four protein bands (and some very weak bands). The four major bands had mol wts of 38.6, 31.6, 30.2, and 29.2 kDa. The last mentioned band was a selenoprotein.  相似文献   

4.
In northern Sweden breeding males of Tengmalm's owls (Aegolius funereus (L.)) were site tenacious during and between the peaks of the vole (staple food) cycles, but females only during the peaks. Most of these adults shifted nest boxes between successive years. They selected nest boxes randomly in a radius of 3 km. Juveniles, in contrast to site tenacious adults, dispersed outside their natal area. The females moved longer than the males prior to their first breeding. Five adult females were found to be nomadic. One of these nomadic females previously bred site tenaciously as long as food was abundant. Juveniles and adult males were not found to be nomadic. Emigration of adult females and juveniles occurred most frequently when vole populations declined. The breeding population increased sharply and received immigrants suggesting that nomadism may be essential in the population dynamics. Site tenacity and nomadism are discussed in terms of costbenefit to males and females, respectively. Emphasis is on the main functional roles of males (feeding femle and young) and females (incubation).  相似文献   

5.
The surface hydrocarbons of the blood-sucking insect, Rhodnius prolixus, a major Chagas disease vector in Venezuela, Colombia and Central America, were characterized by capillary gas chromatography coupled to mass spectrometry (CGC-MS). A total of 54 single or multicomponent peaks of saturated, straight-chain and methyl-branched hydrocarbons were identified. Major n-alkanes were n-C27, n-C29, n-C31 and n-C33 hydrocarbons. In the branched fraction, methyl groups were at positions 3, 5, 7, 11, 13, 15 and 17- for monomethyl isomers, and separated by three or five methylene groups for the trimethyl or tetramethyl derivatives. For the higher molecular weight components of 37, 39 and 41 atoms in the carbon skeleton, the di-, tri- and tetramethyl branches were usually separated by three or five, and sometimes 7, 11 or 13, methylene groups. The internal hydrocarbon pool contained larger amounts of the higher molecular weight methyl-branched components. Qualitative differences among epicuticular and internal hydrocarbon compositions were detected, both in adult and nymphal stages. No significant sexual dimorphism was detected, but a significant shift in the major n-alkane components was evident from the nymphal to the adult stage, differing also in the relative amounts of the higher molecular weight methyl-branched chains. Comparison of the hydrocarbon components to that of other Chagas disease vectors is discussed.  相似文献   

6.
A total of ten larval Ammodytes were collected from the Yellow (5 specimens) and Bering Seas (5), and a 638 base pair sequence from their mitochondrial DNA COI genes was analyzed for species identification. Sequences were compared with those of adult Ammodytes personatus from the East (4), the Yellow (2) and the East China Seas (2), and Japan (3). Average genetic distance was 0.064 between the Yellow Sea larvae and the Bering Sea larvae, but was 0.0043 between the Yellow Sea larvae and all the adult A. personatus except two individuals from the East Sea. NJ-tree showed that five Yellow Sea larvae were closely clustered with adult A. personatus, except for two individuals. The five Bering Sea larvae were located distantly from adult A. personatus, and are thought to be A. hexapterus. We found morphological differences among two populations of A. personatus larvae and A. hexapterus larvae in morphometric characters and pigmentation. Our results indicated that the East Sea population of A. personatus is closer to A. hexapterus than to the Yellow Sea population of A. personatus, suggesting the East Sea population may be part of separate species.  相似文献   

7.
Abstract Parasitoids have long proven to be model organisms in studying resource‐related constraints on immature development. Here we examine the relationship between host cocoon (= pupal) size in the gregarious endoparasitoid wasp, Cotesia glomerata, and development time and adult size in the solitary idiobiont hyperparasitoid, Pteromalus semotus. Little is known about the biology or ecology of this ecto‐hyperparasitoid species, although it is one of the major secondary hyperparasitoids of C. glomerata. The size of the adult wasp covaried with the size of the host cocoon at parasitism. Moreover, female wasps were larger than male wasps for a given cocoon size. Adult wasps have remarkably long life‐spans, 3 months on average. Longevity did not significantly differ with sex. We also examined how larvae of P. semotus exclude other potential competitors. P. semotus is protandrous, with females taking significantly longer to complete their development than males. In experiments where several eggs of P. semotus were placed on individual pupae of C. glomerata, newly hatched hyperparasitoid larvae moved rapidly over the surface of the host and destroyed the eggs of any conspecifics by biting them before they would initiate feeding on host tissues. Our results are discussed in relation to those with other studies with solitary ichneumonid idiobiont hyperparasitoids of C. glomerata.  相似文献   

8.
Eighteen complete daily profiles of 16 behaviors were compiled for three troops of Nilgiri langurs from Periyar Sanctuary in South India. Daily behavioral peaks from these profiles were tested for their associations with each other. Daily rhythms of feeding and resting showed four to eight peaks per day. When all observation days were lumped, however, a bimodal curve resulted as noted by most authors who have studied activity rhythms. The major daily behavioral associations were as follows: (1) feeding occurred during high rates of movement although not during major movement periods; (2) measures of troop movement were interrelated and occurred when troop members were dispersed; (3) movement was related to such active behaviors as whooping displays, coughing, juvenile whining, urinating, and scratching; (4) the above active behaviors showed some positive associations with each other; (5) play, grooming, and scratching showed positive associations with each other; and (6) rest periods were primarily periods of close social contact when grooming occurred and juveniles were with their mothers.  相似文献   

9.
Using behaviourally-defined adjectives, observers rated individuals in a colony of rhesus monkeys on a seven-point scale. Principal component analysis of the ratings produced three main components: CI and CII were stable over three years, and CIII arose from the introduction of new items in the third year. Component I can be described as ranging fromConfident toFearful; and adult males scored higher on it than did adult females or one- to five-year olds. Component II ranged fromActive toSlow; and adult males scored higher on it than did adult females. Component III ranged fromSociable toSolitary; and adult males scored less on it than did adult females or one- to five-year olds. In addition, there was a positive correlation between scores of mothers and their one year olds on CI and CIII.  相似文献   

10.
Morphometric characters on 118 herbarium specimens ofLomelosia crenata subsp.crenata (regarded as including subsp.pseudisetensis) were statistically evaluated to detect discontinuities in the variation pattern. Three morphotypes were detected: specimens with short stems and long calyx bristles, specimens with short stems and short bristles, and specimens with long stems and short bristles. The first morphotypic group is separated from the others, which are partly overlapping. These groups broadly correspond toL. crenata subsp.crenata, toScabiosa crenata var.glabriuscula, and toL. crenata subsp.pseudisetensis, respectively.  相似文献   

11.
The relationship ofAmbrosia (ragweed) andFranseria has long been debated. Their treatment as separate genera has been repeatedly challenged. In this study, chloroplast DNA restriction site variation was examined for species from bothAmbrosia andFranseria as well as taxa from the closely related genusHymenoclea. The chloroplast genomes of members of these three genera were examined using 21 restriction endonucleases and the restriction mutations were used to construct phylogenetic trees. Wagner and Dollo parsimony as well as weighted parsimony were employed to compare the different phylogenies. The results support a close relationship betweenAmbrosia andFranseria, but indicate that the two groups are well separated. Compared toFranseria, Ambrosia is a much more strongly supported group, and the results indicate thatHymenoclea is closer toFranseria than toAmbrosia. The cpDNA phylogeny was used as a framework to examine evolutionary trends in morphology and secondary chemistry.  相似文献   

12.
Functional response experiments were performed in the laboratory to examine the effect of prey density (as observed in the field) on feeding behaviour, and to measure handling-times and attack-rates for each instar and adult of Ranatra dispar Montandon (Heteroptera: Nepidae) feeding on five size-classes of its common prey, Anisops deanei Brooks (Heteroptera: Notonectidae). The most generally applicable response was the Type 2, although for both the predator fifth instar and adult female and male feeding on the two smallest prey sizes, the asymptote or plateau was not observed even at the highest prey density given. Generally, the handling-time increased as prey-size increased, and decreased as the predator size increased. The attack-rate surface was far more complex. For the first two predator instars (I and II), the maximum attack-rate occurred on the smallest prey sizes (1 and 2). The maximum attack-rate for predator instar III was almost the same for prey sizes 1 and 2, that of predator instar IV was greater for prey size 2, while in the three largest predator sizes (V, female and male), the maximum attack-rate was found for prey size 3. Predator instar V had the largest attack-rate values over all prey sizes, and both the predator adult female and male had lower attack-rates for various prey sizes than instars V, IV and, to some degree, III. The results support the suggestion that small predator instars will usually compete with large instars for prey, unless they are spatially or temporally separated. Observations in the field indicate that a distinct age-specific spatial distribution exists in R. dispar and the prey, A. deanei, with the smallest individuals being found predominantly in the shallow (littoral zone) water, while the larger individuals are found in the deeper water.  相似文献   

13.
鄱阳湖越冬白鹤家庭行为   总被引:3,自引:1,他引:2  
张琼  钱法文 《动物学杂志》2013,48(5):759-768
2012年11月至2013年3月,采用焦点取样法,对在江西鄱阳湖国家级自然保护区内越冬的白鹤(Grus leucogeranus)家庭行为进行了研究。结果表明,以家庭为活动单位的白鹤群,成年白鹤活动时间分配比例为:取食80.9%、警戒10.5%、理羽4.0%、游走3.9%、其他0.7%;越冬早期,成年白鹤游走行为的日节律呈现早、晚高,中午低,低谷在10:30~12:30时;越冬晚期,13:00~14:00时出现明显的取食低谷及警戒、游走和理羽的高峰;而越冬早期、中期的理羽高峰出现在14:00~15:00时;成年白鹤雄性与雌性的活动时间分配比例差异不显著;越冬期早、中、晚三个时期,成年白鹤的警戒(F=3.45,P=0.040)、理羽(F=6.99, P=0.001)及游走(F=7.79, P=0.001)行为比例差异显著。幼鹤活动时间分配比例与成年白鹤差异非常显著。幼鹤活动时间分配比例为:取食66.2%、乞食14.0%、警戒3.7%、理羽5.4%、游走3.6%、其他7.1%。雄性成鹤对幼鹤的喂饲频次呈递减趋势,雌性成鹤对幼鹤的喂饲频次从11月底到12月初呈上升趋势,12月中旬以后呈递减状态。整个越冬期,雄、雌成鹤喂饲幼鹤频次无显著性别差异(P=0.340),但越冬中期(P<0.001)及晚期(P=0.005)表现出极显著差异。随着幼鹤的成长,其活动时间节律发生较大变化;幼鹤取食行为比例明显增加,同时其乞食行为的比例显著减少,警戒行为比例显著增加。本次研究从行为学的角度展示了成年白鹤性别差异、幼鹤的生长过程及成鹤对幼鹤生长的重要性。  相似文献   

14.
Multivariate methods were used to compare meristic and morphometric characters of Ammodytes personatus from four populations in Korea (3) and Japan (1). ANCOVA showed the slopes of head length (Japan > East > South > West) and body depth (South > Japan > East > West) relative to total length to differ significantly among populations. Vertebrae and fin rays’ numbers differed significantly among populations, the former ranging between 64 and 67 (mode = 65, 66) in the East population, 62–67 (63, 64) in the West population and 62–64 (62, 63) in the South population in Korea. PCA and CDA, based on 14 morphometric characters, showed that scores plotted on axes 1-2 and 2-3 separated the three Korean populations but overlapped between the South and Japanese populations. These results suggest that the Korean A. personatus may comprise at least two populations. The text was submitted by the authors in English.  相似文献   

15.
Five transgenic rice lines, each containing an insecticidal toxin gene from Bacillus thuringiensis (Bt) under control of a different promoter, were tested for effects on two non-target insects: the brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae), and its predator Cyrtorhinus lividipennis (Hemiptera: Miridae). Bt toxin was detected by ELISA in the honeydew of N. lugens that fed on rice lines with the CaMV 35S and actin promoters. Nilaparvata lugens produced greater volumes of acidic honeydew (derived from xylem feeding) on all five Bt rice lines than on non-transgenic control lines. The amount of honeydew derived from phloem feeding did not differ between Bt and control lines. There were no differences between N. lugens reared on Bt and control lines in any of the five fitness parameters measured (survival to the adult stage, male and female weight, and male and female developmental time). There were no differences between C. lividipennis reared on N. lugens nymphs from Bt and control lines, in any of the three fitness parameters examined (survival to the adult stage and male and female developmental time). Our results indicate that N. lugens and its natural enemies will be exposed to Bt toxins from rice lines transformed with some Bt gene constructs, but that this exposure might not affect N. lugens and C. lividipennis fitness.  相似文献   

16.
A variety of temperature thresholds for larvae, pupae, and adults of seven African species of carrion‐feeding blowflies (Diptera: Calliphoridae) was measured and compared to understand their basic thermal biology and the influence of temperature on their behaviour. Calliphora croceipalpis (Jaennicke) had consistently lower temperature thresholds than all other species tested for all larval (42.9 °C), pupal (16.6 °C), and adult (45.6 °C) stages. Larvae (50.1 °C) and adults (53.4 °C) of Chrysomya marginalis (Robineau‐Desvoidy) had higher upper lethal temperature thresholds than all other species and weighed more than all other species. Pupae and adults of both Chrysomya albiceps (Wiedemann) and Lucilia sericata (Meigen) had similar temperature thresholds, whereas Chrysomya putoria (Wiedemann), Chrysomya chloropyga (Wiedemann), and Chrysomya megacephala (Fabricius) had inconsistent rank temperature thresholds between the larval, pupal, and adult stages. With a few minor exceptions, the nervous activity, muscle activity, and death thresholds in female adult flies responded at higher temperatures than conspecific male flies for all species tested. Similarly, female adult flies weighed consistently more than conspecific male flies for all species tested, except Ca. croceipalpis. These data suggest that there is a phylogenetic component to the thermal biology of blowflies, because Ca. croceipalpis belongs to a primarily Holarctic genus and shows adaptation to that climate even though it inhabits Africa. Comparisons between these temperature thresholds and the distributions of blowfly species present on three rhinoceros carcasses suggest that blowfly larvae with high upper lethal temperature thresholds (particularly C. marginalis) dominate in interspecific competition on the carcass by raising the temperature of the amassed maggots above the thresholds of other carrion‐feeding blowflies, through metabolically generated heat.  相似文献   

17.
Tamarins of the genusSaguinus are small-bodied New World monkeys that exhibit clawlike or modified nails. Patterns of positional behavior and habitat utilization are presented for three species,Saguinus fuscicollis, S. geoffroy, andS. mystax. These data were collected on free-ranging tamarin populations in Panama and Peru. Despite considerable differences in body weight, all three species exhibited very similar patterns of positional behavior, with quadrupedal bounding and running accounting for 43 – 52% of travel time. Leaping was the second most common locomotor activity and accounted for 31 – 41% of travel. Although each species leaped principally on small supports in the perimeter of the tree crown, approximately 20% of all leaps inS. fuscicollis involved moderate to large sized vertical trunks located in the undercanopy. Leaping between trunks was rare in the two larger tamarin species. Measurements taken on live wild-trapped adults reveal that compared toSaguinus geoffroyi andS. mystax, S. fuscicollis is characterized by a long legspan and an especially long armspan. It is proposed that inS. fuscicollis, elongated forelimbs play an important role in maneuvering and rotating the body during the in-air phase of trunk-to-trunk leaping, and increase the breaking distance needed to decelerate the body upon impact. Additional relationships between body size, substrate preference, and positional behavior in callitrichines are discussed.  相似文献   

18.
Pollen adhesion and hydration are the earliest events of the pollen–stigma interactions, which allow compatible pollen to fertilize egg cells, but the underlying mechanisms are still poorly understood. Rice pollen are wind dispersed, and its pollen coat contains less abundant lipids than that of insect‐pollinated plants. Here, we characterized the role of OsGL1‐4, a rice member of the Glossy family, in pollen adhesion and hydration. OsGL1‐4 is preferentially expressed in pollen and tapetal cells and is required for the synthesis of very long chain alkanes. osgl1‐4 mutant generated apparently normal pollen but displayed excessively fast dehydration at anthesis and defective adhesion and hydration under normal condition, but the defective adhesion and hydration were rescued by high humidity. Gas chromatography–mass spectrometry analysis suggested that the humidity‐sensitive male sterility of osgl1‐4 was probably due to a significant reduction in C25 and C27 alkanes. These results indicate that very long chain alkanes are components of rice pollen coat and control male fertility via affecting pollen adhesion and hydration in response to environmental humidity. Moreover, we proposed that a critical point of water content in mature pollen is required for the initiation of pollen adhesion.  相似文献   

19.
We compared day-journey length and daily diets of solitary male gorillas in lowland versus highland habitats. Solitary males in tropical forests of Zaire tend to travel longer distances, to visit more types of vegetation, and to consume more kinds of food than a solitary male mountain gorilla in the Virunga Volcanoes did. The number of feeding sites per day is larger and the mean distance between feeding sites is far longer for the former than the latter. These observations may reflect differences in food breadth and availability between highland and lowland habitats. The herbaceous plants that are eaten by mountain gorillas are densely and evenly distributed in the higher montane forest of the Virungas, where gorillas need not cover long distances to search for food. In contrast, herbaceous plants are scarce in primary and ancient secondary forests of lowland habitats, where gorillas travel long distances and eat various fruits and insects. The patchy and unpredictable distribution of foods may extend the distances over which gorillas search for food in the lowland habitat. However, solitary males showed a prominent reduction in day-journey length and changed their choices of food during the nonfruiting season (the long rainy and dry seasons) in the lowland habitats. This strategy may have developed during the Pleistocene and may have enabled them to enlarge their ranges to the higher montane forests, where fruits are sparse throughout the year.  相似文献   

20.
Three different methods were used to compare the feeding patterns of active cyclopoids and cyclopoids in active diapause from different habitats. First, we offered 14C- labeled algal detritus to stage III, stage IV (two different physiological groups), and adult females of Acanthocyclops vernalis from temporary water-bodies of the Volga Delta. Second, we compared the functional responses of active and actively diapausing cyclopoids preying on copepod nauplii. Stage III, stage IV (various physiological groups), stage V, adult males and females of Acanthocyclops viridis, Cyclops kolensis, C. abyssorum sevani from the Volga Delta, Lake Sevan (Armenia), and Mozhaisk Reservoir (Moscow District) were tested. Finally, we examined the activity of digestive enzymes (proteases) of CIV of C. kolensis from Mozhaisk Reservoir at different temperatures and temperature acclimation regimes. All three approaches used have led to similar conclusions. Actively diapausing cyclopoids were capable of feeding on both plant and animal prey; however, their feeding rates and digestive enzyme activity were 2–8 times lower than those of active cyclopoids of similar size. At the initial stage of active diapause the feeding rates were comparable with those of active cyclopoids then declined to a low level during approximately two weeks. Transfer of cyclopoids undergoing winter diapause from ambient temperature (4 °C) to warmer water (20 °C) resulted in dramatic increase of proteases activity only if the acclimation period was relatively long (two weeks).  相似文献   

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