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Simple Summary: We successfully reared the frugivorous fruit fly pest, Anastrepha ludens, in cost-free fruit waste (orange bagasse), which produced individuals with lower body nutritional content and reduced body weight, and adult males with a highly chemically diverse bouquet of odors, containing eight additional compounds when compared to adults from an artificial diet. Adults from the orange bagasse diet were sexually competitive, but their copulations were significantly shorter than the copulations of males from the artificial diet and males from the wild host plant White Sapote. From a theoretical perspective, our results are relevant because they represent a system that will allow us to study insect evolution from saprophagy to frugivory, as here we grew larvae in a proxy of an ancestral medium. From an applied perspective, our findings are relevant because understanding the role of odors in sexual behavior is key to improving biorational pest control strategies. In addition, mass-rearing pestiferous fruit flies cheaply is an essential component for control programs based on the Sterile Insect Technique. Anastrepha ludens is a polyphagous frugivorous tephritid that infests citrus and mango. Here, we report the establishment of a laboratory colony of A. ludens reared on a larval medium that is a waste for the citrus industry, specifically, orange (Citrus × sinensis) fruit bagasse. After 24 generations of rearing on a nutritionally poor orange bagasse diet, pupae weighed 41.1% less than pupae from a colony reared on a nutritionally rich artificial diet. Larvae from the orange bagasse diet had 6.94% less protein content than larvae from the artificial diet, although their pupation rate was similar. Males from the orange bagasse diet produced a scent bouquet with 21 chemical compounds and were sexually competitive, but they had significantly shorter copulations when compared to males from the artificial diet and from the wild host, Casimiroa edulis, which had relatively simple scent bouquets. The chemical complexity in the odors of males from the orange bagasse diet might initially have attracted females to novel scent combinations, but, once in the copula, they may have been able to sense negative characteristics in males, leading them to terminate copulations soon after they began. We conclude that A. ludens can adjust morphological, life history, nutritional, and chemical traits when adapted to a larval environment consisting of fruit bagasse. [ABSTRACT FROM AUTHOR]

Queens play an essential role in the colonies of stingless bees. Typically, only one queen occurs in a colony at any time, and she dominates the egg laying. Their presence maintains colony cohesion and ensures the development and survivorship of these matriarchal societies. Yet there remain significant gaps in our knowledge of queen life cycles as compared to their daughters, the workers. In this review, we follow chronologically the life of queens from pre-emergence inside brood cells (caste determination), to their interaction with workers (queen selection) and males (sexual selection), and up to adulthood. Stingless bee queens can be determined either trophically or genetically. After emergence, the virgin queens undergo a selection process whereby many are executed by workers. The body size, pheromones, age and behaviour of virgin queens may play a role in queen selection. Queens then leave the nest on a nuptial flight during which they mate just once. After mating, queens are still susceptible to workers' harassment. For example, if they produce diploid males they are killed by workers. Previous studies have successfully in vitro reared and mated virgin queens under laboratory conditions, which have revealed new insights of queen development time, the threshold of minimum and maximum provided food to larvae developing into queens, and lethal and sublethal effects of agrochemical substances. These new techniques have also provided new information about queen physiology. However, the daily routine of queens inside colonies demands further well-designed experiments to capture other patterns of behaviour which remain poorly understood, including their interactions with other queens, workers and even males. [ABSTRACT FROM AUTHOR]

Anastrepha ludens is a polyphagous frugivorous tephritid that infests citrus and mango. Here, we report the establishment of a laboratory colony of A. ludens reared on a larval medium that is a waste for the citrus industry, specifically, orange (Citrus × sinensis) fruit bagasse. After 24 generations of rearing on a nutritionally poor orange bagasse diet, pupae weighed 41.1% less than pupae from a colony reared on a nutritionally rich artificial diet. Larvae from the orange bagasse diet had 6.94% less protein content than larvae from the artificial diet, although their pupation rate was similar. Males from the orange bagasse diet produced a scent bouquet with 21 chemical compounds and were sexually competitive, but they had significantly shorter copulations when compared to males from the artificial diet and from the wild host, Casimiroa edulis, which had relatively simple scent bouquets. The chemical complexity in the odors of males from the orange bagasse diet might initially have attracted females to novel scent combinations, but, once in the copula, they may have been able to sense negative characteristics in males, leading them to terminate copulations soon after they began. We conclude that A. ludens can adjust morphological, life history, nutritional, and chemical traits when adapted to a larval environment consisting of fruit bagasse.

Many basic physiological mechanisms of sexuality were initially studied on animal subjects and conclusions regarding human subjects extrapolated afterward. These ancestral reflexes are assumed to have ascended during human evolution to the cerebral level, where cognition would intermediate (being an environmental operator) both sexual and mental processes. Accordingly, the study of human sexuality suggests an additional/ particular documentation regarding mental existence and its implication, phenomena that are not characteristic of animals. In a previously published paper we presented ideas regarding the structural dichotomy of the mind and its subsequent implications to sexuality. In this paper we present a general perspective regarding the informational dichotomy of the mind and sexuality, which will be followed by a forthcoming paper that addresses the relational dichotomy of the mind and brain. Though these psychological implications may initially seem implausible, they represent in our opinion essential hypothetical perspectives that could further promote a better understanding of both cognition and sexuality.

The mind (mental function) and sexuality represent two distinct environmental functions, but which are supported within the brain by a common (somatic-autonomic) neurobiological substrate. As a consequence, mental function takes on autonomic characteristics from the sexual-autonomic system (like autonomy, duality), while sexual function takes on features from mental functioning (such as lateralization). In this paper we discuss the lateralized action of two classes of sexual neuromodulators: hormones and pheromones. This process of lateralization is assimilated with the structural dichotomy of the mind. A relatively similar process but related to informational dichotomy of the mind will be presented in a forthcoming paper. Structural and informational dichotomies of the mind represent essential aspects that need clarification in order to continue the solving of the mind-body process, a work in progress articulated through a succession of papers.

Pheromone-mediated mating disruption (MD) is widely used as a control tool to manage the European grapevine moth (EGVM), Lobesia botrana. Most of the MD formulations are “passive” reservoir dispensers, which need to be used at a rather large number of units per hectare. A promising alternative is represented by automatic aerosol devices, releasing pheromone puffs at programmed time intervals. Herein, we investigated the effectiveness of MD aerosol product Isonet® L MisterX841 in reducing EGVM infestation on grape in comparison to the reference MD product Isonet® L and the grower’s standard. Experiments were carried out over 2 years in two different study sites of Aragon region (Spain). EGVM male catches were monitored using traps baited with the female sex pheromone. The effectiveness of MD formulations against the three generations of EGVM was assessed by determining the percentage of infested bunches and the number of nests per bunch. As expected, a much greater amount of male catches in the grower’s standard over Isonet® L MisterX841 and Isonet ® L was observed. No significant differences about EGVM male catches were found in vineyards where Isonet® L MisterX841 and Isonet® L were used. EGVM-infested bunches, as well as number of nests per bunch, were higher in the grower’s standard, if compared to vineyards where we tested Isonet® L MisterX841 and Isonet® L. However, the employ of the latter led to a lower EGVM bunch infestation, if compared to Isonet® L MisterX841. Overall, the MD approach proposed here is effective against EGVM. These aerosol devices require a lower number of units per hectare if compared to hand-applied dispensers, saving labor costs and contributing to reduce plastic disposal in agricultural settings. [ABSTRACT FROM AUTHOR]

Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897), the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME) revealed that nerol, neryl formate, pentadecane, (6Z,9Z)-6,9-heptadecadiene, and (Z)-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z)-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z)-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies.

A widely accepted hypothesis for host-plant selection in herbivorous insects is that ovipositing females select host-plants that maximize the survival and performance of their offspring. However, numerous studies indicate that this is not always the case for polyphagous species. Lymantria dispar is a highly polyphagous forest defoliator and has flightless females in some subspecies, resulting in a limited capacity to make host-choices. Males of other Lepidopteran species utilize a combination of sexual pheromones and plant volatiles in their mating choices and exhibit preferences among plant species. We explored the behavior of L. dispar males towards sexual pheromone in the presence and absence of plant volatiles and their ability to discriminate between two plant species with different degrees of suitability for their offspring: a suboptimal host ( Pinus sylvestris), and an optimal host ( Quercus robur). In no-choice wind tunnel assays, we found that rates of male success in locating a pheromone source were not altered by the presence of plant odors; however, the time spent by males searching for the pheromone source after reaching the full length of the tunnel was reduced by more than 50% in the presence of plant volatiles. In dual choice assays, males exhibited a clear preference for a combination of pheromones and plant volatiles over the pheromone alone. However, we did not find evidence of an innate ability to discriminate between the odors of optimal and suboptimal host plants. We discuss possible ecological and evolutionary explanations for these observations. [ABSTRACT FROM AUTHOR]

The leopard moth, Zeuzera pyrina L. (Lep: Zeuzeridae) is an important polyphagous pest of a wide range of trees and shrubs across Europe and Asia. The efficient control of the leopard moth by direct spraying of infested branches and trees is usually impractical because the larvae feed internally and escape from exposure to the used insecticides. Sexual pheromones emitted by females may provide an efficient alternative method to explore the pest, disrupt its mating or capture and kill it. In the present study, we evaluated the efficiency of one Iranian-formulated (in three doses: 1, 1.5, and 2 mg per trap) and three non-Iranian-formulated sexual pheromones in attraction and capturing of adult males of the leopard moth in Walnut orchards of Alborz province and three different regions of Kerman province (Rabor, Baft, Darremorid). We found a wide diversity in response of adult males to different pheromones in the four studied regions. This diversity seems to be resulted from isolation of the populations and may present a preliminary stage of divergence and speciation in this species.

Many basic physiological mechanisms of sexuality were initially studied on animal subjects and conclusions regarding human subjects extrapolated afterward. These ancestral reflexes are assumed to have ascended during human evolution to the cerebral level, where cognition would intermediate (being an environmental operator) both sexual and mental processes. Accordingly, the study of human sexuality suggests an additional/ particular documentation regarding mental existence and its implication, phenomena that are not characteristic of animals. In a previously published paper we presented ideas regarding the structural dichotomy of the mind and its subsequent implications to sexuality. In this paper we present a general perspective regarding the informational dichotomy of the mind and sexuality, which will be followed by a forthcoming paper that addresses the relational dichotomy of the mind and brain. Though these psychological implications may initially seem implausible, they represent in our opinion essential hypothetical perspectives that could further promote a better understanding of both cognition and sexuality. [ABSTRACT FROM AUTHOR]

The mind (mental function) and sexuality represent two distinct environmental functions, but which are supported within the brain by a common (somatic-autonomic) neurobiological substrate. As a consequence, mental function takes on autonomic characteristics from the sexual-autonomic system (like autonomy, duality), while sexual function takes on features from mental functioning (such as lateralization). In this paper we discuss the lateralized action of two classes of sexual neuromodulators: hormones and pheromones. This process of lateralization is assimilated with the structural dichotomy of the mind. A relatively similar process but related to informational dichotomy of the mind will be presented in a forthcoming paper. Structural and informational dichotomies of the mind represent essential aspects that need clarification in order to continue the solving of the mind-body process, a work in progress articulated through a succession of papers. [ABSTRACT FROM AUTHOR]

Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897), the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME) revealed that nerol, neryl formate, pentadecane, (6Z,9Z)-6,9-heptadecadiene, and (Z)-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z)-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z)-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies. [ABSTRACT FROM AUTHOR]

Males of Bombus terrestris (L.) adopt a patrolling behaviour during their nuptial parade using cephalic labial gland (CLG) secretions containing sexual pheromones to attract conspecific virgin queens. The changes in chemical composition of their CLG secretions with age are quite well known. In this study, we investigate the evolution of CLG secretions with age in greater detail and compare behavioural reactions of conspecific virgin queens to the secretions. We show that compounds of CLG secretions follow two profiles. Most of the compounds increase from the first day after emergence until the bees are 15-days-old and then decrease. Others are less abundant in 1 to 15-day-old males and then increase (e.g. tricosane, tricosene, henicosane, tetradecanoic acid, pentacosene, pentacosane, heptacosene, heptacosane, nonacosene and geranylcitronellyl tetradecanoate). Differences in secretion composition lead to preferences of virgin queens for males according to the male's age. Virgin queens prefer the pheromonal gland secretions of bees of the following ages in decreasing order; 1 day = 3 days < 7 days = 30 days < 15 days < 10 days. The virgin queens are strongly attracted by secretions containing high amounts of 2,3-dihydrofarnesol, 2,3-dihydrofarnesal, ethyl dodecanoate and hexadecanol. On the contrary, geranylcitronellol is more abundant in 30-day-old males. [ABSTRACT FROM AUTHOR]

Pyrrolizidine alkaloids (PAs), mainly those with a 1,2-double bond in the necine base moiety (=1,2-dehydropyrrolizidines), constitute a class of well studied compounds with respect to their flux through different trophic levels. Plants belonging to various clades (e.g. Echiteae, Eupatorieae and Senecioneae, Boraginaceae, and Crotalarieae) biosynthesize PAs as N-oxides, generally in the roots, and transport them through the phloem to stems, leaves, and reproductive structures, where they act as potent deterrents against non-specialist herbivores. On the other hand, PA specialist herbivores (mainly arctiid moths, danaine and ithomiine butterflies, and some leaf beetles) have become able to overcome this chemical barrier, and to sequester these alkaloids from their larval host plants or from sources visited by adults, such as flowers and dead or withered plants. Specialists use PAs for their own benefit as chemical defence against a vast array of predators (e.g. ants, lacewings, spiders, lizards, birds, and mammals), but some predators are able to feed on PA-insects, by avoiding or physiologically overcoming PAs present in tissues of the ingested prey. Parasitoids may be affected by PAs, depending on their degree of specialization in relation to PA-insects. Arctiidae, Danainae and Ithomiinae also use PAs as precursors of sexual pheromones. The effects of PAs on trophic interactions have been intensely studied over the last four decades, but some open questions remain, and are discussed, such as the underlying mechanisms that lead to PA diversification, activity of different PA structures, synergism among PAs and other so-called defensive substances in PA-plants, and the ability to overcome this chemical barrier by predators and parasitoids. [ABSTRACT FROM AUTHOR]

The crayfish Procambarus clarkii is a paradigmatic example of aquatic invasive species. Native to north-eastern Mexico and south-central USA, it has today reached a worldwide distribution. Several attempts have been made to mitigate its impacts but none was successful. In this study, we have investigated in the field whether sex pheromones may be used to control invasive populations of this species. Along two canals of the study area (“Padule di Fucecchio”, Central Italy, a wetland of conservation concern), in the summer 2006, we installed 18 traps for each of four types, i.e., (1) empty traps as control, and traps containing (2) sexually receptive males, (3) sexually receptive females, and (4) food. The number, sex, and size of the crayfish captured by each trap in 2 days were recorded and compared among types. The results confirm that males are attracted by the females’ sex pheromones: the sex ratio of the crayfish captured by the traps containing females was significantly biased towards males. However, when the overall number of the captured crayfish was compared among types of trap, food appeared to be the most attractive bait. The method could be improved using purified and concentrated sex pheromone instead of live animals. The use of pheromones has not been successfully applied to control crustacean decapod invaders so far, and a multidisciplinary approach is needed to face the problem. [ABSTRACT FROM AUTHOR]

Human sexual response is a complex function involving many cerebral, spinal and peripheral aspects; the last are relatively known and benefit from good pharmacological control, as in the case of erectile dysfunction. Spinal cord sexual reflexes also have a good theoretical and experimental description. There is minimal understanding of the cerebral sexual processes (libido, sexual arousal, orgasm). The initial perspective was that the cerebral areas implied in sexuality exert descending stimulatory and inhibitory influences on spinal cord sexual centres/reflexes. This was a wrong supposition, which inhibited progress in this subject, with a considerable impact on a subject’s individual and social life. A new approach to sexual function arises from the idea that simple neurological structures can support only simple functions, while a more complex function requires correspondingly complex anatomical structures. For this reason the spinal cord would not be able to realise the integration of multiple (spinal and psychosensorial) stimuli into a unique and coherent ejaculation response. Consequently, all mechanisms implied in human sexuality would be cerebral processes, ejaculation reflexes ascending in evolution to the cerebral level. This new evolutionary concept was developed after 2001 in five distinct articles on the cerebral duality of sexual arousal, sexual hormones, ejaculation and serotonergic receptors. During this period other published results suggested a possible cerebral duality for sexual pheromones and libido in humans. All these dual physiological aspects are integrated in this review into one neurophysiological model, thus trying to further develop the new concepts of sexual function and perhaps relational behaviour. In conclusion, ejaculation is a dual cerebral process with arousal sensation (hormonally modulated) and libido perception (pheromonally modulated) as the afferent part. Two neurophysiological axes could exist in both men and women. In this assumption the mechanisms for libido and sexual arousal are not the only ones invoked, their correlations and implications are also suggested, perhaps critical aspects for further developments in the field. [ABSTRACT FROM AUTHOR]