scholarly journals Costs of deception and learned resistance in deceptive interactions

2014 ◽  
Vol 281 (1779) ◽  
pp. 20132861 ◽  
Author(s):  
Marinus L. de Jager ◽  
Allan G. Ellis
Keyword(s):  
Mating Behaviour ◽  
Multiple Populations ◽  
Antagonistic Coevolution ◽  
Mating Costs ◽  
Ideal System

The costs that species suffer when deceived are expected to drive learned resistance, although this relationship has seldom been studied experimentally. Flowers that elicit mating behaviour from male insects by mimicking conspecific females provide an ideal system for such investigation. Here, we explore interactions between a sexually deceptive daisy with multiple floral forms that vary in deceptiveness, and the male flies that pollinate it. We show that male pollinators are negatively impacted by the interaction, suffering potential mating costs in terms of their ability and time taken to locate genuine females within deceptive inflorescences. The severity of these costs is determined by the amount of mating behaviour elicited by deceptive inflorescences. However, inexperienced male flies exhibit the ability to learn to discriminate the most deceptive inflorescences as female mimics and subsequently reduce the amount of mating behaviour they exhibit on them with increased exposure. Experienced males, which interact with sexually deceptive forms naturally, exhibit similar patterns of reduced mating behaviour on deceptive inflorescences in multiple populations, indicating that pollinator learning is widespread. As sexually deceptive plants are typically dependent on the elicitation of mating behaviour from male pollinators for pollination, this may result in antagonistic coevolution within these systems.

Qualitative and quantitative comparisons of mating behaviour across multiple populations and six species of leiobunine harvestmen (Arachnida: Opiliones)

Behaviour ◽  
2019 ◽  
Vol 156 (3-4) ◽  
pp. 363-390 ◽  
Author(s):  
Kasey Fowler-Finn ◽  
Sarah L. Boyer ◽  
Raine Ikagawa ◽  
Timothy Jeffries ◽  
Penelope C. Kahn ◽  
...  
Keyword(s):  
Sexual Selection ◽  
Body Size ◽  
Morphological Variation ◽  
Mating Behaviour ◽  
Formal Description ◽  
Geographic Diversification ◽  
Multiple Populations ◽  
Qualitative And Quantitative ◽  
High Diversity ◽  
Behavioural Diversity

Abstract Mating behaviour is highly diverse in animals both among and within species. We examine variation in mating behaviour in leiobunine harvestmen, which show high diversity in genitalic traits that are predicted to correspond to patterns of behavioural diversity. We ran mating trials for six species of leiobunine from four locations, and measured body size for a subset of individuals. We described mating behaviour in detail—providing the first formal description for most species—and examined variation inter- and intraspecific in body size and behaviour. Individuals were smaller in northern populations. Furthermore, we found species- and population-specific behaviours, high variation in the timing and success of different stages of mating, and high remating rates. However, we found no correlation between behavioural and morphological variation. Leiobunine harvestmen offer an excellent system for understanding multiple mechanisms of sexual selection and geographic diversification of mating behaviour.

Males increase their fitness by choosing large females in the common bedbug Cimex lectularius

2019 ◽  
Vol 69 (1) ◽  
pp. 17-32 ◽  
Author(s):  
Elena Kaufmann ◽  
Oliver Otti
Keyword(s):  
Mate Choice ◽  
Seminal Fluid ◽  
Mating Behaviour ◽  
Female Size ◽  
Male Mate Choice ◽  
Female Body Size ◽  
Mating Costs ◽  
The Common ◽  
Fitness Benefits ◽  
Male Mate

Abstract Mate choice is often a role assigned to females. Already Darwin realised that males are eager to copulate, and females are choosy. However, male mate choice is not as rare as assumed. Males should choose females if females vary in quality, i.e., fecundity. Indeed, males often choose larger mates and through this preference increase fitness benefits. In addition, if mating costs reduce the number of copulations a male can potentially perform, he should be choosy. Bedbug females vary in their fecundity and female size is positively related to fecundity. Male bedbugs are limited in seminal fluid availability and, hence, the number of consecutive matings they can perform. Traumatic insemination gives males full control over mating, therefore low female mating resistance could further allow males to be choosy. Here, using mate choice arenas, we investigated if male bedbugs prefer to mate with large females. We observed mating behaviour and measured female fecundity to investigate potential male fitness benefits. Males chose to mate with large females 1.8 times more often than small females and large females laid significantly more eggs than small females. Our study provides first evidence for male mate choice based on female body size in bedbugs and males can increase their fitness by mating large females. It has to be further established if male mate choice is driven by mating costs in terms of ejaculate investment and if such male mate choice based on female size could be a driver of sexual size dimorphism in bedbugs.

scholarly journals Inter-genomic sexual conflict drives antagonistic coevolution in harvester ants

2014 ◽  
Vol 281 (1797) ◽  
pp. 20141771
Author(s):  
Michael Herrmann ◽  
Sara Helms Cahan
Keyword(s):  
Sexual Conflict ◽  
Mating Behaviour ◽  
Total Duration ◽  
Sperm Transfer ◽  
Pair Type ◽  
Harvester Ants ◽  
Evolutionary Potential ◽  
Intraspecific Interactions ◽  
Antagonistic Coevolution ◽  
Males And Females

The reproductive interests of males and females are not always aligned, leading to sexual conflict over parental investment, rate of reproduction and mate choice. Traits that increase the genetic interests of one sex often occur at the expense of the other, selecting for counter-adaptations leading to antagonistic coevolution. Reproductive conflict is not limited to intraspecific interactions; interspecific hybridization can produce pronounced sexual conflict between males and females of different species, but it is unclear whether such conflict can drive sexually antagonistic coevolution between reproductively isolated genomes. We tested for hybridization-driven sexually antagonistic adaptations in queens and males of the socially hybridogenetic ‘J’ lineages of Pogonomyrmex harvester ants, whose mating system promotes hybridization in queens but selects against it in males. We conducted no-choice mating assays to compare patterns of mating behaviour and sperm transfer between inter- and intra-lineage pairings. There was no evidence for mate discrimination on the basis of pair type, and the total quantity of sperm transferred did not differ between intra- and inter-lineage pairs; however, further dissection of the sperm transfer process into distinct mechanistic components revealed significant, and opposing, cryptic manipulation of copulatory investment by both sexes. Males of both lineages increased their rate of sperm transfer to high-fitness intra-lineage mates, with a stronger response in the rarer lineage for whom mating mistakes are the most likely. By contrast, the total duration of copulation for intra-lineage mating pairs was significantly shorter than for inter-lineage crosses, suggesting that queens respond to prevent excessive sperm loading by prematurely terminating copulation. These findings demonstrate that sexual conflict can lead to antagonistic coevolution in both intra-genomic and inter-genomic contexts. Indeed, the resolution of sexual conflict may be a key determinant of the long-term evolutionary potential of host-dependent reproductive strategies, counteracting the inherent instabilities arising from such systems.

The in vivo distribution and dynamics of DNA topoisomerase II in Drosophila embryonic nuclei and chromosomes

1993 ◽  
Vol 51 ◽  
pp. 74-75
Author(s):  
Jason R. Swedlow ◽  
Neil Osheroff ◽  
Tim Karr ◽  
John W. Sedat ◽  
David A. Agard
Keyword(s):  
Topoisomerase Ii ◽  
Biochemical Characterization ◽  
Developmental Cycle ◽  
Dna Topoisomerase Ii ◽  
Chromosomal Distribution ◽  
Dna Topoisomerase ◽  
Ideal System ◽  
Dnase Treatment

DNA topoisomerase II is an ATP-dependent double-stranded DNA strand-passing enzyme that is necessary for full condensation of chromosomes and for complete segregation of sister chromatids at mitosis in vivo and in vitro. Biochemical characterization of chromosomes or nuclei after extraction with high-salt or detergents and DNAse treatment showed that topoisomerase II was a major component of this remnant, termed the chromosome scaffold. The scaffold has been hypothesized to be the structural backbone of the chromosome, so the localization of topoisomerase II to die scaffold suggested that the enzyme might play a structural role in the chromosome. However, topoisomerase II has not been studied in nuclei or chromosomes in vivo. We have monitored the chromosomal distribution of topoisomerase II in vivo during mitosis in the Drosophila embryo. This embryo forms a multi-nucleated syncytial blastoderm early in its developmental cycle. During this time, the embryonic nuclei synchronously progress through 13 mitotic cycles, so this is an ideal system to follow nuclear and chromosomal dynamics.

COVID-19 in patients suffering from Cancer: Review article

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 1494-1499
Author(s):  
Shahid Ahmad Siddiqui
Keyword(s):  
Cancer Patients ◽  
Immune Status ◽  
Review Article ◽  
Care Plan ◽  
Patients With Cancer ◽  
Corona Virus ◽  
Cancer Review ◽  
Ideal System ◽  
Lethal Infection ◽  
Set Up

The episode of Covid19 (CORONA VIRUS) has become one of the greatest worldwide dangers around the world, which has now tainted over 1.7 million individuals with deaths of over 100,000 lives far & wide. Under these extraordinary conditions, there are no entrenched rules for cancer patients. The danger for genuine infection & passing in CORONA VIRUS cases increments with propelling age & existing co-morbid medical issue. After the rise of primary suspects in China during last month of 2019, enormous exploration endeavors have been in progress to comprehend the instruments of infectivity & contagiousness of coronavirus, a lethal infection liable for wretched endurance results. To limit the death rate, it gets judicious to distinguish indications quickly & utilize medicines suitably. Despite the fact that no fix has been set up, different clinical preliminaries are in progress to decide the most ideal system. Overseeing patients with cancer in these conditions is a fair task, considering their weak immune status & their ill health. Through this thorough audit, we talk about the effect of CORONA VIRUS on wellbeing & the immune system of who are infected, assessing the most recent care plan draws near & progressing clinical preliminaries. Also, we talk about difficulties confronted while treating cancer patients & propose possible ways to deal with these weak populace during pandemic.

scholarly journals The Infrared Absolute Radiance Interferometer (ARI) for CLARREO

2020 ◽  
Vol 12 (12) ◽  
pp. 1915
Author(s):  
Joe K. Taylor ◽  
Henry E. Revercomb ◽  
Fred A. Best ◽  
David C. Tobin ◽  
P. Jonathan Gero
Keyword(s):  
Brightness Temperature ◽  
New Technologies ◽  
Spectral Radiance ◽  
Overall Design ◽  
Societal Challenges ◽  
Ideal System ◽  
Uncertainty Estimates ◽  
Infrared Spectrometer ◽  
Global Coverage

The Absolute Radiance Interferometer (ARI) is an infrared spectrometer designed to serve as an on-orbit radiometric reference with the ultra-high accuracy (better than 0.1 K 3‑σ or k = 3 brightness temperature at scene brightness temperature) needed to optimize measurement of the long-term changes of Earth’s atmosphere and surface. If flown in an orbit that frequently crosses sun-synchronous orbits, ARI could be used to inter-calibrate the international fleet of infrared (IR) hyperspectral sounders to similar measurement accuracy, thereby establishing an observing system capable of achieving sampling biases on high-information-content spectral radiance products that are also < 0.1 K 3‑σ. It has been shown that such a climate observing system with <0.1 K 2‑σ overall accuracy would make it possible to realize times to detect subtle trends of temperature and water vapor distributions that closely match those of an ideal system, given the limit set by the natural variability of the atmosphere. This paper presents the ARI sensor's overall design, the new technologies developed to allow on-orbit verification and test of its accuracy, and the laboratory results that demonstrate its capability. In addition, we describe the techniques and uncertainty estimates for transferring ARI accuracy to operational sounders, providing economical global coverage. Societal challenges posed by climate change suggest that a Pathfinder ARI should be deployed as soon as possible.

Suppressing Chaos in a Nonideal Double-Well Oscillator Using an Based Electromechanical Damped Device

2014 ◽  
Vol 706 ◽  
pp. 25-34 ◽  
Author(s):  
G. Füsun Alişverişçi ◽  
Hüseyin Bayiroğlu ◽  
José Manoel Balthazar ◽  
Jorge Luiz Palacios Felix
Keyword(s):  
Numerical Simulations ◽  
Chaotic Dynamics ◽  
Duffing Oscillator ◽  
Vibration Energy ◽  
Vibration Absorber ◽  
Electrical System ◽  
Chaotic Vibration ◽  
System A ◽  
Ideal System ◽  
Double Well Potential

In this paper, we analyzed chaotic dynamics of an electromechanical damped Duffing oscillator coupled to a rotor. The electromechanical damped device or electromechanical vibration absorber consists of an electrical system coupled magnetically to a mechanical structure (represented by the Duffing oscillator), and that works by transferring the vibration energy of the mechanical system to the electrical system. A Duffing oscillator with double-well potential is considered. Numerical simulations results are presented to demonstrate the effectiveness of the electromechanical vibration absorber. Lyapunov exponents are numerically calculated to prove the occurrence of a chaotic vibration in the non-ideal system and the suppressing of chaotic vibration in the system using the electromechanical damped device.

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