Females of a solitary bee reject males to collect food for offspring

2020 ◽  
Vol 31 (4) ◽  
pp. 884-891 ◽  
Author(s):  
Ana Laura Dutra ◽  
Clemens Schlindwein ◽  
Reisla Oliveira

Abstract The time dedicated to courtship and copulation is the most general cost of mating for females. However, quantitative estimates of this cost and the consequences for female mating behavior have been investigated for only a few model organisms and mostly under laboratory conditions. We determined the costs of copulations and persistent courtship by males in terms of time for females of the solitary bee Anthrenoides micans. We estimated the rate and duration of male mating behaviors and the consequences for sexual interactions for females with respect to the loss of foraging opportunity in the wild. Males invested most of their time searching for mates and intercepted foraging females every 3 min. Copulas lasted, on average, 10 times longer than the time females took to resist male mating attempts. Despite the high frequency of these rejections (82%), females spent 3-fold more time copulating than rejecting males. Considering the rate of encounters with males and the mean duration of flower visits by females, we estimated that females would perform 64% fewer flower visits per hour if they accepted all copulation attempts. The loss of time is especially significant in the natural habitat of the species, where host cacti blossom for extraordinary short periods of time and females compete with other cacti-specialized bees and conspecifics. Because the offspring production of a female solitary bee depends on its pollen collection capacity, reduced foraging performance directly influences female reproductive success.

Genetics ◽  
2002 ◽  
Vol 162 (4) ◽  
pp. 1863-1873 ◽  
Author(s):  
J Slate ◽  
P M Visscher ◽  
S MacGregor ◽  
D Stevens ◽  
M L Tate ◽  
...  

Abstract Recent empirical evidence indicates that although fitness and fitness components tend to have low heritability in natural populations, they may nonetheless have relatively large components of additive genetic variance. The molecular basis of additive genetic variation has been investigated in model organisms but never in the wild. In this article we describe an attempt to map quantitative trait loci (QTL) for birth weight (a trait positively associated with overall fitness) in an unmanipulated, wild population of red deer (Cervus elaphus). Two approaches were used: interval mapping by linear regression within half-sib families and a variance components analysis of a six-generation pedigree of >350 animals. Evidence for segregating QTL was found on three linkage groups, one of which was significant at the genome-wide suggestive linkage threshold. To our knowledge this is the first time that a QTL for any trait has been mapped in a wild mammal population. It is hoped that this study will stimulate further investigations of the genetic architecture of fitness traits in the wild.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aditya Ghoshal ◽  
Anuradha Bhat

AbstractShoaling decisions in the wild are determined by a combination of innate preferences of the individual along with the interplay of multiple ecological factors. In their natural habitat as well as in the laboratory, zebrafish is a shoaling fish. Here, we investigate the role of group size and associated vegetation in shaping shoaling preferences of wild male zebrafish. We studied the association preference of males to groups of female shoals in a multi-choice test design. We found that males made greater proportion of visits to an 8-female group compared to 2 and 4-female groups. However, males spent similar proportions of time across the three female-containing groups. When artificial vegetation was incorporated along with female number as an additional factor, we found that males prefer high and moderately vegetated patches compared to low or no-vegetation groups, irrespective of the number of females in these patches. Based on experiments using a novel multi-choice design, our results show that preference for group size can change due to interaction of two separate factors. This work is a first attempt to understand the role of aquatic flora in determining shoaling preferences in zebrafish, using an experimental paradigm consisting of a gradation in female and vegetation densities.


Genetics ◽  
1985 ◽  
Vol 109 (1) ◽  
pp. 157-175
Author(s):  
Ward B Watt ◽  
Patrick A Carter ◽  
Sally M Blower

ABSTRACT Male mating success as a function of genotype is an important fitness component. It can be studied in wild populations, in species for which a given group of progeny has exactly one father, by determining genotypes of wild-caught mothers and of sufficient numbers of their progeny. Here, we study male mating success as a function of allozyme genotype at two glycolytic loci in Colias butterflies, in which sperm precedence is complete, so that the most recent male to mate fathers all of a female's subsequent progeny.—For the phosphoglucose isomerase, PGI, polymorphism, we predict mating advantage and disadvantage of male genotypes based on evaluation of their biochemical functional differences in the context of thermal-physiological-ecological constraints on the insects' flight activity. As predicted, we find major, significant advantage in mating success for kinetically favored genotypes, compared to the genotype distribution of males active with the sampled females in the wild. These effects are repeatable among samples and on different semispecies' genetic backgrounds.—Initial study of the phosphoglucomutase, PGM, polymorphism in the same samples reveals heterozygote advantage in male-mating success, compared to males active with the females sampled. This contrasts with a lack of correspondence between PGI and PGM genotypes in other fitness index or component differences.—Epistatic interactions in mating success between the two loci are absent.—There is no evidence for segregation distortion associated with the alleles of either primary locus studied, nor is there significant assortative mating.—These results extend our understanding of the specific variation studied and suggest that even loci closely related in function may have distinctive experience of evolutionary forces. Implications of the specificity of the effects seen are briefly discussed.


2021 ◽  
Vol 6 (1) ◽  
pp. 58612
Author(s):  
Silvi Dwi Anasari ◽  
Wulan Pusparini ◽  
Noviar Andayani

The distribution of a species can help guide the protection activities in their natural habitat. Conversely, the lack of information on this distribution makes the protection strategy of this species difficult. The research was conducted in Way Canguk Research Station, Bukit Barisan Selatan National Park from January until March 2018. The purposes of this research were to create a distribution prediction map of Sunda pangolin (Manis javanica) and estimating the environment variables that most influenced the probability of the distribution. Fourteen points of camera trap coordinates were used for presence data with nine types of environment variables such as elevation, slope, understorey, canopy cover, distance from roads, distance from rivers, distance from villages, food source, and distance from the threat. The result of maxent showed an Area Under the Curve (AUC) value of 0.909 categorized as very good. The highest probability of Sunda pangolin distributions was in the Pemerihan Resort and Way Haru Resort area, while the dominant environmental variables included the distance from the village, the canopy cover, and the distance from threat with the value 47.7; 25.85; and 15.8%, respectively. Prediction maps and environment variables can help to identify the population of Sunda pangolin in the wild and can provide input for the national parks to prioritize protection areas for Sunda pangolin from the increased poaching.


1967 ◽  
Vol 45 (6) ◽  
pp. 937-948 ◽  
Author(s):  
J. L. Nichols ◽  
B. G. Lane

Ribosomal ribonucleates from Escherichia coli have been resolved into 16S and 28S components by sucrose density-gradient centrifugation, and the chain termini in each of the 16S and 23S RNA components have been analyzed by hydrolysis with alkali. The principal 5′-linked end group of 16S RNA was found to be adenosine, and the principal 5′-linked end group of 23S RNA was found to be uridine. The principal 3′-linked end group of 16S RNA was also found to be adenosine, whereas the principal 3′-linked end group of 23S RNA was found to be guanosine. Quantitative estimates of chain length based on analyses for 5′-iinked terminals indicate that the mean chain length for 16S RNA is about 1.3 × 103nucleotide residues and the mean chain length for 23S RNA is about 2.1 × 103nucleotide residues.


2021 ◽  
Vol 13 (13) ◽  
pp. 20056-20065
Author(s):  
Maria Theresa ◽  
Appukuttan Kamalabai Sreekala ◽  
Jayalakshmi Mohanlal

Ophiorrhiza caudata is a creeping, perennial herb distributed along wet and shady areas. The species is distylous with two distinct floral morphs: pin and thrum. Flowering usually occurs during the monsoon season. No particular difference was noticed in the flowering phenology of the two morphs. Presently the species is self-incompatible, however, it shows a tendency towards intramorph compatibility. Fruit set is above 60% in open pollination and intermorph pollination. Bees and butterflies are the major pollinators. The pollen flow between the two floral morphs varies depending upon floral morphology and pollinators. Fruit is a bi-valved capsule which dehisces by a splashing drop mechanism. The seeds are very minute. The rate of seed germination and seedling establishment in the wild condition is very poor due to adverse climatic factors. Ophiorrhiza caudata is struggling for survival in its natural habitat, where habitat fragmentation, climatic factors and poor seedling establishment could account for its narrow distribution.


Author(s):  
Fabio Castaño Rivera ◽  
Julián Botero Arango

Two groups of adult Mutton snapper fish Lutjanus analis captured in the wild, each one of three females and four males, were kept during eight months under controlled temperature and photoperiod conditions in the lab in order to stimulate their sexual maturation which was in a state of latency because of the effects of confinement. The first group was maintained under an artificial cycle with temperature manipulation and the second under a control cycle, in which this parameter was left at natural conditions. Every two months blood samples from all females were taken for the analysis of plasma testosterone (T) and oestradiol (E2) levels, taking ovarian biopsies simultaneously to register the mean diameter of the oocytes. After six months, a significative increase in the mean diameter of the oocytes of the three females of the artificial cycle was observed, with coincidence and statistic relationship with the increase in the T and E2 (r = 0.62 y 0.82 respectively). No oocyte growth was observed in the females under the control cycle. In both, artificial and control cycles, T and E2 levels showed a close relationship with photoperiod (r = 0.84 y r = 0.61) while temperature showed a lower or non significant relationship (r = 0.40 y r = 0.20). Statistical differences (P<0.1) were found between the condition factors of the two groups, while the sexual steroids didn’t show any differences between them. The present work constitutes the first report on the analysis of sexual steroid levels during the gonadal maturation process in fish of the Family Lutjanidae kept under an artificial conditioning cycle.


Genome ◽  
2001 ◽  
Vol 44 (4) ◽  
pp. 517-522 ◽  
Author(s):  
M Martínez ◽  
T Naranjo ◽  
C Cuadrado ◽  
C Romero

Different wild allopolyploid species of Triticeae show extensive bivalent formation at zygotene while a considerable number of multivalents is present in cultivated polyploid wheats. To study the chromosome behaviour at early meiotic stages in wild forms of tetraploid wheats Triticum turgidum and T. timopheevii (2n = 4x = 28) we have analysed the synaptic pattern in fully traced spread nuclei at mid- and late zygotene and at pachytene of wild accessions of these species. The mean number of synaptonemal complex (SC) bivalents at mid-zygotene ranged from 12.22 to 13.14 among the accessions studied indicating a strong restriction of synapsis initiation to homologous chromosomes. The mean of bivalents increased at pachytene because of the transformation of multivalents into bivalents. Ring bivalents observed at metaphase I support that SC bivalents were formed by homologous chromosomes. The average values of SC bivalents at mid-zygotene in the wild forms are much higher than the average values observed in the cultivated tetraploid wheats but similar to that of a mutant line of T. turgidum with a duplication that includes Ph1, the major homoeologous pairing suppressor locus. These results suggest that the efficiency of the mechanism operating in the homologous recognition for synapsis is higher in wild wheat populations than in cultivated varieties. Apparently, a relatively detrimental modification of the pairing regulating genetic system accompanied the domestication of the wild wheat forms.Key words: Ph1 locus, Triticum turgidum, Triticum timopheevii, synaptonemal complex, diploidisation.


2012 ◽  
Vol 90 (5) ◽  
pp. 677-681 ◽  
Author(s):  
A. South ◽  
S.M. Lewis

In many insects, nuptial gifts in the form of spermatophores have been shown to increase female fecundity and to contribute to female somatic maintenance. Examining how variation in male spermatophore size affects female fitness components can provide insight into the evolution of nuptial gifts, as well as insight into potential conflicts between the sexes. Here we present an experimental study on the firefly Photinus obscurellus LeConte, 1851 in which we altered spermatophore size by manipulating male mating history and examined effects on female offspring production and longevity. Females were randomly allocated to one of two mating treatments in which they mated once with a male producing either a large or a small spermatophore. We found that male spermatophore size had no significant effect on lifetime fecundity or daily reproductive rates of female P. obscurellus, but females that received a larger spermatophore showed a tendency toward longer postmating life spans. These results suggest a direct benefit to females from nuptial gifts and also reveal the potential for synergistic effects on multiple facets of female fitness.


1995 ◽  
Vol 18 (1) ◽  
pp. 1
Author(s):  
R.T. Gemmell

The brushtail possum is a common arboreal marsupial that is well adapted to the Australian urban environment and to rearing in captivity. Data obtained from 100 female possums housed in a semi-captive colony over a 7 year period demonstrate the reproductive capability of this marsupial. The main breeding season is from March to June with a declining number of births occurring from July to October. The possums gave birth to 259 single young and one set of twins. The range of the lactation period was from 177 to 200 days with the birth of the subsequent young occurring at 188.4 ± 4.1 days post partum (SD, n = 5). The growth rate of the young female possum varied greatly after day 100 post partum, the mean body weight of possums at day 172, being 753.0 ± 76.2g (SD, n = 5) with a range of 685 to 851 g. Female possums, with a mean body weight of 2171 ± 388g, gave birth to their first litter on day 345.9 ± 69.3 days postpartum (mean, SD, n = 7). Although two female possums trapped in the wild were held in captivity for 64 and 63.4 months and one possum bred in captivity had a life span of 51.5 months, the mean life span was 21.0 ± 12.5 months (SD, n =3D 8), with a range of 14.3 to 51.5 months. This life span is very variable and it is of interest to determine if this is an artefact of captivity or is also observed in the wild.


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