Male Social Behavior and Dominance Hierarchy in the Sulawesi Crested Black Macaque (Macaca nigra)

In a 6-week study of the social behavior of wild Sulawesi crested black macaques (Macaca nigra), we found a linear and transitive dominance hierarchy among the six adult males in one social group. Dominance rank, as determined by the direction of supplantations, correlated strongly with percentage of time near more than four neighbors, frequency of grooming received from adult females, and percentage of time with an adult female as nearest neighbor. These results suggest that high-ranking males are socially attractive. Adult females sexually solicited high-ranking males more often than low-ranking males, but frequency of copulation was not correlated with dominance rank. Frequency and intensity of aggression between males are strongly correlated with rank distance, but aggression toward females was greatest for mid-ranking males. Males of all rank displayed significantly more aggression toward sexually receptive females than toward females in other estrous states. These data indicate that male Sulawesi crested black macaques display a social organization similar to that reported for multimale groups in other macaque species rather than the egalitarian social organization described for female Sulawesi macaques.     

Sexual differences in the flight performance of the oriental fruit moth, Cydia molesta

Cydia molesta Busck (Lepidoptera: Tortricidae), a major pest of stone fruits and an increasingly important late season pest of apple, is predominately monitored by pheromone trapping of male moths. We investigated flight performance in relation to sex, age, and mating status using computer-linked flight mills, and also examined the relationship between female flight and reproduction. The crepuscular flight pattern of the experimental moths in relation to photointensity was very similar to that reported from field studies. Female moths significantly outperformed males in all measured flight parameters including total distance flown, distance of longest single flight, and velocity. The proportion of long-flying females (categorised as those completing an unbroken flight of greater than 1 km) was three to six times greater than that of males. Female flight performance was not related to mating status, but mated males displayed significantly greater flight than unmated males. The maximal flight period of mated females commenced on the third day after eclosion, following 30% egg deposition. Male flight was not significantly related to age. The data suggest that a limited proportion of the population, in particular females, may have the capacity to make inter-orchard flights. The limitations of monitoring C. molesta populations in apple orchards solely by pheromone trapping of males are discussed.     

千岛湖岛屿社鼠的扩散特征

2009年7月—11月,2010年3月—11月对千岛湖两个岛屿上的社鼠(Niviventer confucianus)种群进行标志重捕,通过分析扩散个体的性别、年龄及扩散距离等,探讨陆桥岛屿环境下社鼠的扩散特征。研究结果显示:岛屿环境下社鼠的扩散率为37.96%,不同季节社鼠的扩散率存在差异,社鼠倾向于在春季发生扩散,尤其是3月份,社鼠扩散个体数最多;对于整个捕获史而言,雌雄扩散个体数存在极显著的差异(x~2=12.542,df=1,P0.001),雄性个体更倾向于发生扩散;而在繁殖高峰期,当怀孕鼠存在时,雄性扩散数亦大于雌性,两者存在显著差异(x~2=4.504,df=1,P=0.034)。扩散个体体重的季节差异不显著;扩散与社鼠的年龄密切相关,社鼠更加倾向于在亚成年阶段发生扩散;另外,家群大小对社鼠扩散个体数量也有显著影响,家群越大,扩散个体越多;对扩散距离进行分析发现存在显著的性别差异(t=-9.229,df=50,P0.001),雌性个体的平均扩散距离为(282.97±16.14)m,显著大于雄性的(146.70±6.80)m,而扩散距离与年龄、体重、最大活动距离均无显著相关性。     

社群等级对金乌贼行为表型及能量代谢的影响

采用实验生态学方法,在室内水槽条件下研究了金乌贼(Sepia esculenta Hoyle,1885)繁殖过程中社群等级的形成对其行为表型和能量代谢的影响,分析测定了不同优势等级雌雄个体腕部肌肉和性腺组织中己糖激酶(Hexokinase, HK)、丙酮酸激酶(Pyruvate kinase, PK)、乳酸脱氢酶(Lactate dehydrogenase, LDH)、苹果酸脱氢酶(Malate dehydrogenase, MDH)、柠檬酸合酶(Citrate synthetase, CS)活性以及乳酸(Lactic acid, LD)含量。结果显示:(1)金乌贼繁殖期不同优势等级雌雄个体之间行为表型具有显著差异,优势雄性个体游动悬浮、争斗时间显著高于劣势个体,而优势雌性个体静止伏底时间高于劣势个体,游动悬浮时间低于劣势雌性;(2)优势雄性个体在争斗过程中主要通过无氧代谢提供能量,而处于游动悬浮状态时通过有氧代谢提供能量。主要表现在优势雄性个体肌肉中无氧代谢酶(PK、HK、LDH)活性显著高于劣势个体(P0.05),有氧代谢酶(MDH、CS)活性也显著高于劣势个体,雌性个体之间则差异不显著(P0.05);(3)繁殖期雌性个体通过减少运动量来储存能量用于产卵繁殖,主要表现在优势雌性个体肌肉中有氧代谢酶(MDH、CS)活性低于劣势个体,而在性腺中恰恰相反;(4)运动表型与能量代谢之间存在显著相关性,表现在游动悬浮时间与有氧代谢酶(MDH、CS)活性呈显著正相关(P0.001),争斗时间与无氧代谢酶(PK、HK、LDH)及乳酸(LD)含量呈显著正相关(P0.05)。结果表明,社群等级高的雄性个体运动能力强,具有较高的生存适应性。而社群等级高的雌性个体多处于静止状态,以便更好地储存能量用于繁殖。研究结果为金乌贼健康苗种培育以及规模化繁殖技术优化提供了理论依据。     

Age structure and body size of the Chuanxi Tree Frog Hyla annectans chuanxiensis from two different elevations in Sichuan (China)

Age, body size, and growth patterns in the subtropical anuran Hyla annectans chuanxiensis from high (Dengchigou Protection Station) and low (Lingguan Town) elevations in Baoxing County of Sichuan province (China) were described using skeletochronology. Females were significantly older than males at the low-elevation site, but there was no significant difference between the sexes at the high-elevation site. Age at sexual maturity of both males and females was 2 years at the high-elevation site, whereas males matured at 1 year and females at 2 years at the low-elevation site. Males and females from the low-elevation population reached a maximum age of 3 and 4 years, respectively, whereas males and females from the high-elevation population reached a maximum age of 4 and 5 years, respectively. At both sites, females were significantly larger than males. Females and males from the high-elevation population were larger than individuals from the low-elevation population. When the effect of age was controlled, the differences in body size of the two populations were significant only for females. Von Bertalanffy growth curves indicated that the growth rates in males was greater than in females in both populations. They also showed that the growth of both sexes slowed at an earlier age in the low-elevation population than in the high-elevation population. The findings suggest that age is a major factor underlying body size patterns for both sexes, but that the elevation of the locality affects the body size of females.     

金乌贼繁殖行为与交配策略

2014年6月于室内大型水槽使用摄像系统对金乌贼繁殖过程进行连续观察与记录,通过定性和定量比较分析,解析其繁殖过程中游泳、捕食、求偶、争斗、交配及产卵等行为特征。结果显示:金乌贼游泳主要依靠漏斗喷水的反作用力,持续游泳能力较弱;繁殖期的金乌贼继续摄食,能发现周围20—38 cm范围内的凡纳滨对虾,攻击距离为7—24 cm,能在2.1—6.1 s内完成对对虾的捕获且成功率极高,外源营养为卵(精)巢不同步发育、分批产卵和复杂的繁殖行为继续提供能量支持;金乌贼具明显的求偶行为,规格差异是影响求偶的重要因素,其中雄性亲本更倾向选择与自身规格相当或略小的雌性,而雌性亲本则更倾向于选择大规格(较大规格争斗易获胜)的雄性;金乌贼一次交配持续125—398 s,雄性有明显的精子移除行为和领域性,交配后雄性伴游在雌性周围3—24 cm范围内,不允许其他乌贼靠近,平均伴游61 min后会再次交配。精子移除、伴游以及多次交配是雄性金乌贼有效提高父权贡献率的关键行为基础;研究结果表明,金乌贼采取"多夫多妻"的混交婚配策略,两性亲本均存在多次交配现象,这能有效提高雌雄的生殖成功率和受精卵的遗传多样性。     

Vocal Diversity and Taxonomy of Nomascus in Cambodia

It is usually thought that Nomascus gabriellae is the only Nomascus sp. in Cambodia. We studied vocal diversity among different wild populations of Nomascus in Cambodia to assess their taxonomic relationships and to examine whether their vocal patterns correspond to forms previously described for Nomascus leucogenys siki and Nomascus gabriellae. We tape-recorded crested gibbon songs in southern Mondulkiri Province, in central Rattanakiri Province, and in 2 different districts of the Virachey National Park in northern Rattanakiri. We also tape-recorded typical songs of Nomascus leucogenys siki near the type locality of the taxon in the Bach Ma National Park in central Vietnam. We analyzed 40 song bouts from different gibbon groups, including 151 phrases of 33 females and 235 phrases of 39 males. Discriminant analyses revealed marked separation of the most southern songs (Mondulkiri) from those of all other localities. Vocal differences among the 3 gibbon populations in northeast Cambodia (Rattanakiri) are less pronounced; they do not differ more among each other than each of them differs from the northernmost sample from Bach Ma (Vietnam). Vocal characteristics of the study populations revealed no cline, and populations do not differ significantly in vocal variability. We conclude that Cambodian crested gibbons represent 2 distinct taxa: Those from southern Mondulkiri are Nomascus gabriellae, those from northeast Cambodia (Rattanakiri) closely correspond to the sample from Bach Ma (Vietnam) and, together with the latter, represent a different taxon. We provisionally assign them to Nomascus leucogenys siki because of the close geographic distance between Bach Ma and the type locality of the taxon. We postulate that a taxonal boundary exists between southern Mondulkiri and central Rattanakiri and discuss the possible factors that may have acted as distribution barriers.     

同种雄性竞争对手的存在对星豹蛛雄蛛求偶和交配行为的影响

越来越多的研究发现,雄性产生精子(精液)也需付出代价。雄性除了依据配偶质量和竞争对手的竞争强度适应性调整生殖投入外,雄性在求偶和交配行为上也相应产生适应性反应,求偶和交配行为具有可塑性。目前雄性求偶和交配行为可塑性研究主要集中于雌性多次交配的类群中,在雌性单次交配的类群中研究甚少。以雌蛛一生只交配一次而雄蛛可多次交配的星豹蛛为研究对象,比较:(1)前一雄性拖丝上信息物质对后续雄蛛求偶和交配行为的影响,(2)雌雄不同性比对雄蛛求偶和交配行为的影响。研究结果表明,星豹蛛前一雄蛛拖丝上的信息物质对后续雄蛛求偶潜伏期、求偶持续时间和交配持续时间都没有显著影响,但前一雄蛛拖丝上的信息物质对后续雄蛛求偶强度有显著抑制作用。同时,性比对星豹蛛雄蛛求偶和交配行为都没有显著影响。可见,星豹蛛雄蛛对同种雄性拖丝上的化学信息可产生求偶行为的适应性调整,而对性比不产生适应性反应。     

Protandry and postandry in two related butterflies: conflicting evidence about sex-specific trade-offs between adult size and emergence time

Natural selection acting on timing of metamorphosis can be sex-specific, resulting in differences in timing between males and females. Insects with discrete generations frequently show protandry: males usually mature before females. Both Euphydryas editha and E. aurinia butterflies followed this trend. The present study was motivated by the unusual observation of consistent postandry in addition to protandry. In a single E. editha population observed over 20 years the emergence period of males was longer than that of females, both the first and last emerging individuals being males. Variance of timing among individual E. editha larvae is imposed by spatial patchiness of the snowmelt that releases them from winter diapause. If individual larvae released late from diapause were to compensate for their lateness by shortening their development times, they would be small at maturity. If such compensation were only partial, they would be both late and small. Size and timing would become associated. If females were more prone to such partial compensation than males, the observations of postandry could be explained and the prediction made that any tendency for late individuals to be small should be stronger in females than in males. This was the case: in 1 year late males were the same size as early males, in a second year they were larger. Late females were significantly smaller than early females in both years. In E. aurinia, results were opposite both to theoretical prediction and to the observations from E. editha: although the male emergence period was longer than that of females exactly as in E. editha, late males were smaller than early ones, while late females were not small. The data from E. editha support the hypothesis of a sex-specific trade-off between size and emergence time, the data from E. aurinia do not.     

白背叶(大戟科)性系统和传粉生物学研究

为探讨野桐属(Mallotus)雌雄异株的进化和传粉机制,对白背叶(Mallotus apelta)野生居群的性系统和传粉生物学进行了研究。结果表明,所调查的白背叶居群均由雌性(F)、雄性(M)和少数两性(B)个体组成,平均性比为1：0.66：0.18(F：M：B);3种性别植株的基径大小差异不显著;雌株与两性植株的单花胚珠数、单果结籽数和自然结实率无显著差异;雄株与两性植株的花粉萌发率、花粉组织化学和花粉微形态特征也无显著差异,但雄株的单花花粉量是两性植株的1.26~1.63倍,且差异显著;雌株的异交结实率为96.67%,两性植株的异交结实率为76.00%,两者差异显著,说明居群内雌株的潜在种子生产力明显高于两性植株;野外观察到雄株和两性植株上的雄花具有访花者而雌株没有;雌株经套网处理后结实率超过30%而套袋处理不结实。这些表明白背叶具典型的亚雌雄异株性系统,雌株和雄株的适合度均高于两性植株;雌株以风媒传粉结实,两性植株可能兼有风媒和虫媒传粉特征。     

Asymmetric size effect of sexes on reproductive fitness in an aphid parasitoid Aphidius ervi (Hymenoptera: Aphidiidae)

Most studies on size–fitness relationships focus on females and neglect males. Here, we investigated how body size of both sexes of an aphid parasitoid, Aphidius ervi Haliday, affected the reproductive fitness. Reproductive fitness was generally positively correlated with body size for both sexes in this species. Large individuals of both sexes had greater longevity, large males fathered more progeny, and large females had higher fecundity, parasitism, and greater ability in host searching and handling. We demonstrated in this study that size effects of males and females were asymmetric on different reproductive fitness parameters. With increasing body size females gained more than males in longevity and fecundity while males gained more than females in the number of female progeny. Regardless of female size, large males sustained a female-biased population longer than small males. These results suggest that male body size should also be considered in the quality control of mass-rearing programs and the evaluation of parasitoid population growth.     

Spatial organization of the fat dormouse (Glis glis) in an oak-hornbeam forest during the mating and post-mating season

Home range (HR) size and overlap, movements, and nest site use of fat dormice Glis glis (Linnaeus, 1766) were studied by live-trapping and radiotracking in the Bialowieza Forest in north-eastern Poland. The study was conducted during a mast year of oak Quercus robur (2001) and hornbeam Carpinus betulus (2002). Average HR size measured by 100% minimum convex polygons varied from 3.6 to 7.0 ha in males and from 0.55 to 0.76 ha in females. HR size in males was significantly larger in the hornbeam mast year than in the oak mast year, which was probably due to the lower energy value of hornbeam mast. Males had significantly larger HRs and used more nest sites than females. In contrast to females, HRs of males overlapped extensively. In the mating season, core areas of males overlapped significantly more and they shared their core areas with more males than in the post-mating season. During the mating season, males were found to share nest sites with other males or with a single female. Additionally, groups of 2–3 males were observed aggregating around a female during the mating season. Our data suggest that fat dormice have a promiscuous mating system where the females are territorial, and the non-territorial males directly compete for access to receptive females during the mating season.     

Population and reproductive biology of the fiddler crab Uca thayeri Rathbun, 1900 (Crustacea: Ocypodidae) in a tropical mangrove from Northeast Brazil

Population and reproductive biology of Uca thayeri Rathbun, 1900 were studied for the first time in a tropical mangrove. Absolute density, sex ratio, population structure, handedness, breeding season and fecundity were investigated. Seven transects were delimited in a mangrove area of the Pacoti River, Northeast of Brazil (3° 43′ 02″ S/38° 32′ 35″ W). On each transect, ten 0.25 m² squares were sampled on a monthly basis during low tide periods from September 2003 to August 2004. A total of 483 crabs were obtained, of which 250 were males, 219 non-ovigerous females, and 14 ovigerous females. The U. thayeri population presented bi-modal size frequency distribution, with males and non-ovigerous females not differing significantly size-wise. Ovigerous females were larger than males and non-ovigerous females. The overall sex ratio (1:1.07) did not differ significantly from the expected 1:1 proportion. The major cheliped was the right one in 50% of the males. The observed density was of 8.5 individuals/m², with the specimens being found mostly in shaded areas. Ovigerous females were found in 5 months of the year, coinciding with the rainy season, suggesting that the population of U. thayeri presents seasonal reproductive events. Juvenile crabs were more abundant during the dry period, while larger crabs were found mainly during the rainy period. The fecundity of the studied population was much smaller than that of subtropical populations of this species. The regression analysis shows that the number of eggs increases linearly with the increase of carapace width.     

Party composition and dynamics inPan paniscus

The pygmy chimpanzee, or bonobo, Pan paniscus,diplays a fission-fusion social organization in which individuals associate in parties that vary in size and composition. Data from a 2-year field study of nonprovisioned P. paniscusshow that party composition varies with party size. Although females, on average, outnumber males, the proportion of males in the party increases in larger parties. This effect was not due to the greater number of known females. Both females and males will join and leave a party in the company of others, but only males appear frequently to join or leave as lone individuals. All-male parties were not observed, but all-female (nonnursery) parties were relatively common. These trends reflect greater cohesion among females than observed in P. troglodytes schweinfurthii.Cohesion between males and female P. paniscusmay increase with party size.     

Localization and antioxidant capacity of flavonoids from intertidal and subtidal Halophila johnsonii and Halophila decipiens

In this study, flavonoid localization, content and total antioxidant capacity in leaves of subtidal Halophila decipiens were compared to intertidal and subtidal Halophila johnsonii. H. johnsonii leaves had significantly higher flavonoid content (3.5 and 3.8 nmol quercetin equivalent mm⁻² leaf for intertidal and subtidal H. johnsonii, respectively) and antioxidant capacity (101.7 and 224.2 nmol Trolox equivalent mm⁻² leaf for intertidal and subtidal H. johnsonii, respectively) than H. decipiens leaves (1.4 nmol quercetin equivalent mm⁻² leaf and 21.0 nmol Trolox equivalent mm⁻² leaf). Flavonoid content did not significantly differ between intertidal and subtidal H. johnsonii, however, antioxidant capacity was significantly higher in subtidal plants. Confocal laser scanning microscopy of fresh leaf cross sections indicated that both species contained flavonoids in the cuticle, but only H. johnsonii contained intracellular flavonoids. Intracellular flavonoids are better situated to perform antioxidant functions in planta. These results suggest that flavonoid compounds in H. johnsonii are capable of sunscreen and antioxidant functions while an antioxidant role for flavonoids within H. decipiens is not supported.     

Chemical composition of femoral secretions of oviparous and viviparous types of male common lizards Lacerta vivipara

In spite of the importance of chemoreception in intraspecific communication of lizards, only a few studies have examined chemical composition of secretions of lizards. The secretion of the femoral glands of adult male lizards Lacerta vivipara contains a relatively low number (18) of lipophilic compounds in comparison with other related lacertid lizards. These compounds were identified on the basis of mass spectra, obtained by GC-MS. Chemicals included ten steroids (mainly cholesterol) and four carboxylic acids between n-C₁₂ and n-C₁₈, and minor components such as squalene, α-tocopherol, and two waxy esters, which may contribute to avoid oxidation of other lipophilic components in the fairly humid environments occupied by this lizard. Secretions of adult males from oviparous and viviparous populations did not differ in the numbers and quality of chemical compounds, but there were some differences in the relative proportion of some compounds. Males from oviparous populations had lower proportions of hexadecanoic acid and cholestan-3-one, and higher proportions of squalene than viviparous males. These differences might be explained by either small genetic differences between types or due to different microclimatic conditions in the original populations.     

棉铃虫成虫对两种关键花香气味的联系性学习

为了明确棉铃虫对苯乙醛和乙酸苯甲酯两种关键花香气味的联系性学习行为,在室内分别测定了不同学习训练的棉铃虫雌雄成虫对两种关键花香气味的选择偏好性反应和雄成虫的触角电位反应。偏好性测定结果表明,无花香气味接触经历的棉铃虫对苯乙醛和乙酸苯甲酯的选择频次均无显著差异,且单纯的花香气味接触经历也不能诱导棉铃虫气味偏好性的显著改变,唯有花香气味接触经历伴随蔗糖溶液进行强化训练时,才能诱导气味偏好性的显著性改变。从对两种花香气味的联系性学习看,棉铃虫更容易将苯乙醛与蔗糖溶液进行联系性学习,而不容易将乙酸苯甲酯与蔗糖溶液进行联系性学习。从性别差异看,雌虫比雄虫具有更强的将花香气味与蔗糖溶液进行联系性学习的能力。触角电位测定结果表明,不同学习训练的棉铃虫雄成虫对两种花香气味和绿叶气味顺-3-己烯-1-醇的EAG反应值之间不存在显著性差异。总之,花香气味伴随食物资源的联系性学习经历,能够明显提高棉铃虫成虫对花香气味的选择偏好,可以此为基础进一步优化花香引诱剂的配方设计和应用技术。     

Genetic variability in the reactive distance inTrichogramma brassicae after automatic tracking of the walking path

Efficiency of hymenopterous parasitoids to control pests in a biological control release program probably increases with increasing searching ability of the females, which, in return, likely depends on the distance from which females perceive their hosts (i.e., reactive distance). In this study, we first analyse this hypothesis with the help of a stochastic model simulating the walking path of isolatedTrichogramma females during their searching behaviour. Then, this reactive distance is estimated using automatic recording and analysis of the walking path of female wasps. Finally, the genetic variability for this trait is analysed in aTrichogramma brassicae Bezdenko (Hym.; Trichogrammatidae) population. Three types of hosts were used: Eggs ofEphestia kuehniella Zeller (Lep.; Pyralidae), eggs ofMamestra brassicae L. (Lep.; Noctuidae) and 0.45 mm glass beads.M. brassicae eggs are perceived from 4.01±0.15 mm, which is a significantly longer perceptive distance than forE. kuehniella eggs (3.69±0.10 mm) and glass beads (3.67±0.10 mm). Moreover, whatever the host tested, a significant genetic variation is observed in this trait in the population studied. The ecological and evolutionary implications and the agronomical importance of these results are discussed.     

Behavior, Diet, and Movements of the Sulawesi Crested Black Macaque (Macaca nigra)

We present the first field study of activity budgets, diet and ranging patterns of the Sulawesi crested black macaque, Macaca nigra, one of seven macaque species endemic to Sulawesi, Indonesia. We studied three crested macaque groups, ranging in size from 50 to 97 individuals, for 18 months in the Tangkoko-DuaSudara Nature Reserve, North Sulawesi. They spent 59% of the day moving and procuring food, especially fruits, and 41% of the day resting and socializing. Their diet is composed of more than 145 species of fruit (66% of observed feeding bouts), vegetative material (2.5%), invertebrates (31.5%), and occasional vertebrate prey. Group differences were more pronounced than seasonal or diurnal differences. Specifically, the largest group moved farther during the day, moved at a faster and more uniform rate, ate less fruit, rested more, and socialized less than the smaller groups did. The largest group had the largest home range, but it included less primary forest and more disturbed habitat than the ranges of smaller groups. There are individual differences in activity budgets of adult males and females in time spent moving, resting, feeding, and socializing that may reflect differences in reproductive strategies of males versus females. The behavior of large juveniles is more similar to that of adults than to that of small juveniles. Daily movements and use of home range are correlated with diet. Macaques moved shorter distances as the proportion of time spent feeding on fruit increased, and the top four dietary items accounted for most of the variance in entry into hectare blocks of home range.     

Sexual behavior in brown capuchins ( Cebus apella )

We observed sexual behavior patterns in two captive groups of Cebus apella.We obtained data on intersexual solicitations and intersexual competition. The length of proceptivity cycles by females averaged 18.8 ± 1.2 days; this corresponds with published reports of physiological measures of ovulatory cycles. Females initiated sexual interactions with males significantly more than males initiated interactions with females, and female solicitations increased in frequency over the duration of displayed periods of proceptivity. In contrast, male solicitations of females were infrequent and did not change significantly throughout female proceptive phases. Each female solicited the same male throughout a given proceptive phase. We observed no evidence of male-male or female-female competition. Males seem to respond to female sexual behavior directed toward them, rather than initiating sexual interactions themselves. Even so, male sexual interactions with females followed only a small proportion of solicitations.