Variation in flight morphology in a female polymorphic damselfly: intraspecific, intrasexual, and seasonal differences

2009 ◽  
Vol 87 (1) ◽  
pp. 86-94 ◽  
Author(s):  
J. Bots ◽  
C. J. Breuker ◽  
A. Van Kerkhove ◽  
S. Van Dongen ◽  
L. De Bruyn ◽  
...  

In aerial animals, flight morphology needs to be designed to allow daily behavioural activities. Within species differences in behaviour can therefore be expected to relate to differences in flight morphology, not only between males and females but also between same-sex members when they use different behavioural strategies. In female polymorphic damselflies, one female morph is considered a male mimic that resembles the male’s body colour and behaviour (andromorph), whereas the other is dissimilar (gynomorph). Here, we questioned whether males, andromorphs, and gynomorphs of the damselfly Enallagma cyathigerum (Charpentier, 1840) differ in flight morphology, with andromorphs being more similar to males than gynomorphs. In addition, we evaluated whether differences in flight morphology are consistent or whether some morphs are more plastic in response to seasonal environmental fluctuations. Most morphometrics showed similar seasonal plasticity for males and both female morphs, which could only partly be explained from allometry. Consistent with high manoeuvrability in flight, males had broader wings and lower wing loading than females. Variation between female morphs was less pronounced, with no consistent differences in length, aspect ratio, total surface, and wing loading. However, we detected morph-specific differences in shape and width, with andromorphs having broader wings than gynomorphs similarly to males.

Author(s):  
David A. Hamburg ◽  
Beatrix A. Hamburg

In the past several decades, the study of the behavior of nonhuman primates—monkeys and apes—has made rapid progress. We can learn from the dimly perceived past when our ancestors confronted the problems of survival without the sophisticated technological aids so inextricably linked to human adaptation in recent times. Our past is inaccessible to direct study. But by careful observation of our closest living relatives, monkeys and apes, we can begin to understand the nonhuman primate heritage from which our ancient ancestors took a long route over millions of years toward humanity. Nonhuman primates live in groups that are held together by strong and enduring bonds between individuals. These bonds may be reflected in a variety of ways: relationships between adult males and females, between adults of the same sex, between juveniles, and between adult males or females and their young. Altogether, in their natural habitats they have a rich social life. Compared with most other mammals, primates have fewer young at a time. Rather than litters, all Old World monkeys and apes have only one offspring at a time, and they give each one a great deal of attention. The young have longer periods of immaturity than other mammals, including prolonged nutritional dependence on the mother. A corollary of the prolonged physical immaturity and nutritional dependence of the primate infant is a longer and more intense mother- infant relationship and a longer period of tutelage and learning the customs and survival skills of the group. In all higher primates except humans, infants cling reflexively to their mothers from birth, and mother-infant contact is maintained virtually all of the time until the much older infant develops the ability to keep up with the mother on its own. Nursing occurs in many short bouts around the clock; in early infancy, it is initiated and terminated by the infant, an easy process, because the infant is always clinging to the mother’s body, anyway. This combination of clinging, carrying, continuous contact, and frequent nursing is characteristic of all higher nonhuman primates.


2020 ◽  
Vol 31 (3) ◽  
pp. 731-738 ◽  
Author(s):  
Simon Vitt ◽  
Iris Madge Pimentel ◽  
Timo Thünken

Abstract While the importance of kin discrimination, that is, kin recognition and subsequent differential treatment of kin and nonkin, is well established for kin-directed cooperation or altruism, the role of kin discrimination in the context of kin competition and kin avoidance is largely unexplored. Theory predicts that individuals avoiding competition with kin should be favored by natural selection due to indirect fitness benefits. Using an experimental approach, we investigated whether the presence of same-sex kin affects avoidance and explorative behavior in subadult Pelvicachromis taeniatus, a West African cichlid fish with strong intrasexual competition in both sexes. Pelvicachromis taeniatus is capable of recognizing kin using phenotype matching and shows kin discrimination in diverse contexts. When exposed to a same-sex conspecific, both males and females tended to interact less with the related opponent. Moreover, individuals explored a novel environment faster after exposure to kin than to nonkin. This effect was more pronounced in females. Individuals avoiding the proximity of same-sex relatives may reduce kin competition over resources such as mating partners or food.


The Auk ◽  
1987 ◽  
Vol 104 (4) ◽  
pp. 640-646 ◽  
Author(s):  
Ray T. Alisauskas

Abstract I studied morphometric variation in 13 linear measurements from 228 American Coots (Fulica americana) collected in southern Manitoba. Univariate and multivariate techniques revealed differences in size and shape among adult coots that were 1, 2, and =2 yr old. In addition to the obvious differences in size between males and females, the morphometry of older birds differed from that of younger birds in two ways. First, older coots were of larger body size than younger coots of the same sex. Second, older coots had proportionately larger feet and claws relative to the size of their tarsi, and proportionately wider bills and heads relative to other head measurements, than did younger birds. Multivariate dispersion matrices within age/sex cohorts were less variable for older coots. In an analysis of 1-yr-old males, breeders did not differ from nonbreeders in overall body size, but breeders had relatively longer claws and wings than nonbreeders. Age-related differences in morphology may have relevance to the social structure of nesting coots, which involves highly aggressive territorial behavior. Part of the age-related variation in nesting phenology that has been documented elsewhere for coots may be a consequence of covariation in body size and shape.


Science ◽  
2019 ◽  
Vol 365 (6456) ◽  
pp. eaat7693 ◽  
Author(s):  
Andrea Ganna ◽  
Karin J. H. Verweij ◽  
Michel G. Nivard ◽  
Robert Maier ◽  
Robbee Wedow ◽  
...  

Twin and family studies have shown that same-sex sexual behavior is partly genetically influenced, but previous searches for specific genes involved have been underpowered. We performed a genome-wide association study (GWAS) on 477,522 individuals, revealing five loci significantly associated with same-sex sexual behavior. In aggregate, all tested genetic variants accounted for 8 to 25% of variation in same-sex sexual behavior, only partially overlapped between males and females, and do not allow meaningful prediction of an individual’s sexual behavior. Comparing these GWAS results with those for the proportion of same-sex to total number of sexual partners among nonheterosexuals suggests that there is no single continuum from opposite-sex to same-sex sexual behavior. Overall, our findings provide insights into the genetics underlying same-sex sexual behavior and underscore the complexity of sexuality.


2005 ◽  
Vol 53 (3) ◽  
pp. 157 ◽  
Author(s):  
Amy C. Rogers

In many tropical bird species, partners combine their songs to form precise duets, of which the function is imperfectly understood. Duet structure and sex differences in vocal strategies may be important indicators of different selective pressures that have led to the evolution and maintenance of these complex acoustic displays. This study examines the singing behaviour of a population of the eastern whipbird, a bird that forms antiphonal duets initiated exclusively by the male. In all, 7% of duets recorded were between a paired female and a male other than her social partner. Males sang more often than females, their songs were longer and moved through a wider frequency range, and they had a larger song repertoire. Females sang two types of song: response songs, used primarily in a duet context, and structurally distinct solo songs, typically used during interactions with other females. Eastern whipbirds lacked unique song types among the repertoires of individual males and females. Males and females combined songs non-randomly to produce specific duets that were shared across the population. Results suggested that song and duet type matching might play an important role in intrasex interactions, such as defence of a territory, or a partner, from same-sex intruders.


1986 ◽  
Vol 18 (4) ◽  
pp. 471-478 ◽  
Author(s):  
S. Araki ◽  
H. Aono ◽  
K. Murata ◽  
I. Shikata ◽  
Y. Mitsukuni

SummarySeasonal variations in cause- and age-specific suicide rates in males and females were analysed in Osaka, Japan, for the years 1974–83, using profile analysis. Significant cause differences were found in males: (1) the rate for poisoning by domestic, car-exhaust or other gases was high in winter and spring and low in summer and autumn; (2) the rate for hanging, strangulation and suffocation was low in winter; (3) the rate for a variety of violent methods (chemicals, firearms, drowning, etc.) was high in summer. Similarly, there were sex differences in the variation for causes (2) and (3) and for ages 40–54. No significant age difference was found in either sex. Seasonal differences in the ease of suicidal methods and sex- and season-specific psychosocial factors were thought to be the major determinant of the seasonal variation.


Behaviour ◽  
1992 ◽  
Vol 123 (1-2) ◽  
pp. 38-69 ◽  
Author(s):  
Rachel A. Smolker ◽  
Andrew F. Richards ◽  
Richard C. Connor ◽  
John W. Pepper

AbstractPatterns of association among bottlenose dolphins resident in Shark Bay, Western Australia were analyzed using party membership data. Parties contained an average of 4.8 individuals, but party size and composition were unstable. While these temporary parties often contained both males and females, long term consistent associations generally were between members of the same sex. The highest association coefficients, resulting from very frequent co-occurrence within parties were between males and between mothers and offspring. Males formed subgroups of two or three individuals who consistently associated with each other, and these were stable over periods of at least seven years in some cases. Male subgroups preferentially associated with particular other male subgroups. Females associated most consistently with other females, although not to the same extent as some males. Female associations were better described as a network rather than discrete subgroups. Male-female associations were generally inconsistent and depended in part on female reproductive state. Mothers and their offspring associated very consistently for at least 4 years.


2021 ◽  
Vol 15 ◽  
Author(s):  
Fabrice de Chaumont ◽  
Nathalie Lemière ◽  
Sabrina Coqueran ◽  
Thomas Bourgeron ◽  
Elodie Ey

Ultrasonic vocalizations (USVs) are used as a phenotypic marker in mouse models of neuropsychiatric disorders. Nevertheless, current methodologies still require time-consuming manual input or sound recordings clean of any background noise. We developed a method to overcome these two restraints to boost knowledge on mouse USVs. The methods are freely available and the USV analysis runs online at https://usv.pasteur.cloud. As little is currently known about usage and structure of ultrasonic vocalizations during social interactions over the long-term and in unconstrained context, we investigated mouse spontaneous communication by coupling the analysis of USVs with automatic labeling of behaviors. We continuously recorded during 3 days undisturbed interactions of same-sex pairs of C57BL/6J sexually naive males and females at 5 weeks and 3 and 7 months of age. In same-sex interactions, we observed robust differences between males and females in the amount of USVs produced, in the acoustic structure and in the contexts of emission. The context-specific acoustic variations emerged with increasing age. The emission of USVs also reflected a high level of excitement during social interactions. We finally highlighted the importance of studying long-term spontaneous communication by investigating female mice lacking Shank3, a synaptic protein associated with autism. While the previous short-time constrained investigations could not detect USV emission abnormalities, our analysis revealed robust differences in the usage and structure of the USVs emitted by mutant mice compared to wild-type female pairs.


Zootaxa ◽  
2021 ◽  
Vol 4927 (1) ◽  
pp. 41-57
Author(s):  
BRADLEY J. SINCLAIR ◽  
SCOTT E. BROOKS ◽  
JEFFREY M. CUMMING

The Empis (Enoplempis) mira species group is revised and includes the type species of Enoplempis and four new species (E. macdonaldi sp. nov., E. submira sp. nov., E. williamturneri sp. nov., E. winkleri sp. nov.). A lectotype is designated for Enoplempis mira Bigot. The species group is defined by the yellow body colour, directionally asymmetrical male hindlegs and geniculate hindlegs in both males and females. The group has not been found outside of western North America and is known from California, Oregon, Idaho and Washington. 


2021 ◽  
Author(s):  
Sarah Catherine Paul ◽  
Caroline Müller

AbstractStudies on intraspecific contest behaviour predominantly focus on contests between individuals of the same sex, however contest behaviour is also expected to occur between individuals of the opposite sex including possible mates. Here we investigate potential trade-offs between mating and fighting behaviour in the turnip sawfly (Athalia rosae). Adults of this species collect chemical defence compounds (clerodanoids) directly from plants but also indirectly by nibbling on conspecifics that have already obtained clerodanoids themselves, a highly aggressive behavioural interaction. An A. rosae individual without clerodanoids may therefore be the potential mate or attacker of an individual of the opposite sex that has gained clerodanoids. We paired males and females with or without clerodanoid access and manipulated body mass differences between the sexes via the early life starvation of females. We show that asymmetrical clerodanoid acquisition between male-female pairs causes an increase in agonistic nibbling behaviour, irrespective of sex. Moreover, fighting over clerodanoids disrupted mating behaviour, and the frequency of aggressive nibbling behaviour in these pairs was determined by the comparative body mass of the attacking individual. Our study highlights the vital importance of investigating agonistic intersex interactions not only over mating but also over resources.


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