A new mode of parental care in cockroaches

Summary A new form of maternal provisioning of newly hatched nymphs is described in the ovoviviparous cockroach Gromphadorhina portentosa. Shortly after expelling the hatching egg case, the female exudes from her abdominal tip a whitish, translucent material on which neonates actively feed. Integumentary gland cells lining the brood sac are the most likely source of the secretion. This form of maternal provisioning may not be restricted to the Madagascar hissing cockroach; a glandular brood sac similar to that of G. portentosa is found in at least three additional ovoviviparous cockroaches.Received 22 January 2003; revised 4 March 2003; accepted 19 March 2003.     

The Sound and the Fury—Bees Hiss when Expecting Danger

Honey bees are important model systems for the investigation of learning and memory and for a better understanding of the neuronal basics of brain function. Honey bees also possess a rich repertoire of tones and sounds, from queen piping and quacking to worker hissing and buzzing. In this study, we tested whether the worker bees’ sounds can be used as a measure of learning. We therefore conditioned honey bees aversively to odours in a walking arena and recorded both their sound production and their movement. Bees were presented with two odours, one of which was paired with an electric shock. Initially, the bees did not produce any sound upon odour presentation, but responded to the electric shock with a strong hissing response. After learning, many bees hissed at the presentation of the learned odour, while fewer bees hissed upon presentation of another odour. We also found that hissing and movement away from the conditioned odour are independent behaviours that can co-occur but do not necessarily do so. Our data suggest that hissing can be used as a readout for learning after olfactory conditioning, but that there are large individual differences between bees concerning their hissing reaction. The basis for this variability and the possible ecological relevance of the bees’ hissing remain to be investigated.     

Communication in the courtship of a madagascan hissing cockroach. I. Normal courtship

The hissing Madagascar cockroach, Gromphadorhina portentosa, has a prolonged and complex courtship involving signals in several sensory modalities. Courtship was described for 13 pairs of cockroaches and the frequencies and sequencing of 16 behavioural units were analysed. Particular attention was paid to the function and interactions of acoustic, chemical and tactile components. The results indicate that posturing and sound production by males, and antennation by both males and females, are important in courtship. They also suggest that courtship in G. portentosa, rather than depending on a rigid sequence of behaviour determined by a series of discrete releasers, is quite flexible, using ‘behavioural monologues’ by both sexes as a means of achieving transitions from one stage of courtship to the next.     

Male Mating Success in the Presence of a Conspecific Opponent in a Madagascar Hissing Cockroach,Gromphadorhina portentosa (Dictyoptera: Blaberidae)

The influence of a conspecific competitor on male mating behavior was examined in a Madagascar hissing cockroach, Gromphadorhina portentosa. Previous studies have suggested that both male-male competition and female discrimination during courtship interactions may influence male mating success. Familiar pairs of males with a known social association were placed in an arena with a single virgin female and observed. As expected, subordinate males mated significantly less often than their dominant opponents. In pairs in which one male mated, dominant individuals limited the access of subordinates to females. Dominant males displayed an increased frequency and duration of interaction with the female. However, in pairs where both males remained unmated, the mating behavior of dominant and subordinate males did not differ significantly. As interactions progressed, as in the case of males that remained unmated, subordinate males gained increased access to the female. Mated males tended to be larger than their opponent although within a rank, males that mated were no larger than those that remained unmated. These results are discussed in light of the possible roles of male-male competition and female discrimination during courtship interactions.     

Patterns of aggregation behaviour in six species of cockroach: comparing two experimental approaches

Cockroaches (Blattaria) are considered universally gregarious insects. In this study, we tested the hypothesis that even related species and/or males and females of the same species may exhibit different aggregation patterns. We compared aggregation behaviour in six cockroach species belonging to three groups: Eublaberus, Blaberus, and Gromphadorhina‐Princisia (all Blaberidae). For comparison, binary choice and free aggregation arena tests were used. The results revealed that blaberid clades clearly differed in their aggregation patterns. Females of Eublaberus species aggregated, whereas only a low aggregation tendency was recorded in conspecific males. Both sexes of Blaberus species aggregated, especially when tested in the arena. The Madagascar hissing cockroaches of the Gromphadorhina‐Princisia clade are not gregarious – the aggregation tendency was entirely absent in males of the two species studied and in females of Princisia vanwaerebeki van Herrewege, and was only weakly demonstrated in females of Gromphadorhina portentosa (Schaum). The observed patterns of aggregation are compared with previous reports concerning social behaviour of blaberid species.     

Demonstration of kinetochores and centrioles in spermatocytes of two species of cockroaches by silver staining

Light microscopy following silver staining of spermatocytes of German and Madagascar hissing cockroaches demonstrated: (1) the localization of a kinetochore in each autosomal synaptonemal complex during pachytene, and (2) visualization of centrioles in different stages of meiotic prophase. The presence of a hairpin-like twist and the nucleolus organizer region in the X-chromosome was observed only in the German cockroach.On leave from the Kunming Institute of Zoology, The Chinese Academy of Sciences, Peoples Republic of China     

Measurement of arthropod body composition using quantitative magnetic resonance

Quantitative magnetic resonance (QMR) is a new technology for measuring the body composition (wet lean mass, fat mass, and total body water mass) of unrestrained and unanesthetized animals. We conducted a validation study using two species of crayfish (mass range 5.5–27 g), American lobsters (680–732 g), and Madagascar hissing cockroaches (6.5–14 g) to assess the utility of QMR for quantifying the body composition of crustaceans and other large arthropods. A comparison of crayfish, lobster, and cockroach wet lean, fat, and body water masses calculated by QMR with those obtained from the traditional chemical extraction method demonstrates that QMR is a valid technology for analysis of wet lean mass and body water. Fat mass could not be accurately predicted, although this might be improved with the use of a QMR analyzer designed specifically for animals of low fat content. QMR analysis allows rapid (<4 min) and non‐destructive determination of body composition in field and lab environments, enabling researchers to conduct longitudinal studies and to increase the ethicality and practicality of studying rare or threatened species.     

Fine structural description of the compound eye of the Madagascar 'hissing cockroach'Gromphadorhina portentosa (Dictyoptera: Blaberidae)

The compound eyes of the wingless adults of the Madagascar ‘hissing cockroach’Gromphadorhina portentosa Sachum, 1853 were examined by light and electron microscopy. Each eye contains 2 400‐2 500 mostly hexagonal facets. However, irregularities affecting both shape and size of the ommatidia are relatively common, especially towards the margins of the eye. An individual ommatidium of this eucone type of apposition eye contains eight retinula cells, which give rise to a centrally‐fused, tiered rhabdom. The distal end of the latter is funnel‐shaped and accommodates the proximal end of the cone in its midst. Further below, the rhabdom (then formed by the rhabdomeres of four retinula cells) assumes a squarish profile with microvilli aligned in two directions at right‐angle to each other. Cross sections through the proximal regions of the rhabdom display triangular rhabdom outlines and microvilli (belonging to 3‐4 retinula cells different from those involved in the squarish more distal rhabdom) that run in three directions inclined to one another by 120°. Overall the organization of the eye conforms to the orthopteroid pattern and particularly closely resembles that of the American cockroach Periplaneta americana. However, since G. portentosa possesses fewer ommatidia, this could be a consequence of its inability to fly. On the other hand, the large size of the facets and the voluminous rhabdoms suggest considerable absolute sensitivity and an ability to detect the plane of linearly polarized light. Based on the pattern of microvillus orientations in combination with the crepuscular lifestyle G. portentosa leads and the habitat it occurs in, the prediction is made that this insect uses its green receptors for e‐vector discrimination in the environment of down‐welling light that reaches the forest floor.     

Is hissing behaviour of incubating great tits related to reproductive investment in the wild?

Anti-predator behaviour of breeding animals is a complex trait that depends on current reproductive investment as well as individual differences in risk-taking propensities. In response to nest predation, many bird species produce specific sounds, such as the hissing calls in incubating great tits (Parus major), that may provoke an acoustic startle response in the predator. However, it is still unclear whether the propensity of incubating females to produce hissing calls towards nest predators depends on the reproductive investment. With our 3-year study, we show that response type (females that do not hiss versus females giving hissing calls) to a potential nest predator, the woodpecker, is a repeatable trait. We found no differences in the studied reproductive traits between hissing and non-hissing birds. Interestingly, among hissing birds, fast-responding females started egg-laying earlier than slow-responding ones. Among non-hissing birds, heavier birds initiated clutches earlier. We also revealed that hissing birds breed in areas with decreased nest-box occupancy, suggesting either that they potentially select different areas to breed or that territory size is larger as a result of hissing birds being more aggressive. These findings demonstrate that response type is not related to the early reproductive value of the brood across distinct behavioural groups. However, our results do suggest that non-hissing and hissing females differ in terms of individual quality or dominance or personality related aspects.     

Hissing females of great tits (Parus major) have lower breeding success than non‐hissing individuals

Antipredator strategies vary remarkably between individuals within populations. Parents tend to take greater risks when brood value is increased. Moreover, individuals consistently differ in a whole suite of correlated behaviours that may cause distinctive responses to predators. It is likely that individual differences in antipredator behaviour may co‐vary with proxies for fitness such as reproductive success. We used a 4‐year data from wild great tits (Parus major) to test whether passive and active antipredator strategies (females with no response vs. those giving hissing calls towards a nest predator) during the incubation stage can reflect variation in breeding success. Although clutch size did not depend on hissing behaviour, the number of surviving offspring from eggs and neonates to fledglings was higher for non‐hissing than hissing birds. We conclude that females with distinct antipredator strategies can prioritize different fitness components.     

Habituation of hissing by Madagascar hissing cockroaches (Gromphadorhina portentosa): evidence of discrimination between humans?

Anecdotal reports suggest that insects can be "tamed" with frequent human contact. In the present experiment, repeated handling of Madagascar hissing cockroaches by the same person resulted in habituation of the hissing response in ten of 12 subjects. These subjects were then handled by a novel person in order to determine whether habituation might be specific to a particular human. Four of ten "habituated" subjects immediately began to hiss in the presence of the novel handler, but again ceased hissing when contact with the familiar person was reestablished. Our results suggest that in some cases "taming" may be person-specific, rather than a generalized response to humans. These preliminary findings are the first evidence of discrimination between humans by an insect species, although comparable results are well documented in mammals and birds.     

Susceptibility of cockroaches (Gromphadorhina portentosa,Nauphoeta cinerea and Blaptica dubia) exposed to entomopathogenic nematodes

Cockroaches are major pests, vectors of pathogenic bacteria and induce allergies. Current control methods use chemical pesticides, but they can be ineffective and costly and there are reports of resistance in the field; hence new control methods are needed. There are conflicting reports about the susceptibility of cockroaches to entomopathogenic nematodes (EPNs); so we investigated if EPNs could kill several diverse cockroach species, including the Madagascan hissing roach (Gromphadorhina portentosa), the Lobster roach (Nauphoeta cinerea) and Blaptica dubia. Female adult cockroaches were exposed to either commercial products containing Steinernema kraussei or a combination of Heterorhabditis spp. and Steinernema spp. at 50 and 150 nematodes per cm² for 21 days. We also monitored feeding and the numbers of infective juveniles that were produced from each cockroach corpse. We found that S. kraussei were harmless to all cockroach species (at both doses) but when exposed to a mixture of Heterorhabditis spp. and Steinernema spp. B. dubia died after 6 days and its feeding was strongly inhibited. We also found that the mixture of Heterorhabditis spp. and Steinernema spp. could proliferate in the cadavers of B. dubia whilst S. kraussei could only reproduce in G. portentosa and B. dubia but not N. cinerea. In conclusion, S. kraussei was harmless to all three cockroach species but B. dubia was killed when exposed to Heterorhabditis spp. and Steinernema spp., highlighting the differences in the host range of EPNs.     

Effective Stimulus Parameters for Directed Locomotion in Madagascar Hissing Cockroach Biobot

Swarms of insects instrumented with wireless electronic backpacks have previously been proposed for potential use in search and rescue operations. Before deploying such biobot swarms, an effective long-term neural-electric stimulus interface must be established, and the locomotion response to various stimuli quantified. To this end, we studied a variety of pulse types (mono- vs. bipolar; voltage- vs. current-controlled) and shapes (amplitude, frequency, duration) to parameters that are most effective for evoking locomotion along a desired path in the Madagascar hissing cockroach (G. portentosa) in response to antennal and cercal stimulation. We identified bipolar, 2 V, 50 Hz, 0.5 s voltage controlled pulses as being optimal for evoking forward motion and turns in the expected contraversive direction without habituation in ≈50% of test subjects, a substantial increase over ≈10% success rates previously reported. Larger amplitudes for voltage (1–4 V) and current (50–150 μA) pulses generally evoked larger forward walking (15.6–25.6 cm; 3.9–5.6 cm/s) but smaller concomitant turning responses (149 to 80.0 deg; 62.8 to 41.2 deg/s). Thus, the radius of curvature of the initial turn-then-run locomotor response (≈10–25 cm) could be controlled in a graded manner by varying the stimulus amplitude. These findings could be used to help optimize stimulus protocols for swarms of cockroach biobots navigating unknown terrain.     

Hissing calls improve survival in incubating female great tits (Parus major)

Nest predation is among the most important selective pressure shaping nest-site selection and nest defense behavior in many avian species. In this study, we tested whether the production of one such nest defense behavior—hissing calls—may improve survival of incubating female great tits (Parus major). We found that 72.5 % of incubating females gave hissing calls when they were exposed to a stuffed woodpecker in their nest boxes. The repeatability of the number of hissing calls given was high, as was the latency to give the call. Additionally, natural nest predators attacked hissing and nonhissing females equally often. However, hissing females survived better than silent females. We tested responses of feral cats to playbacks of hissing call during their attacks of nest boxes and found that hissing calls prevented the predator attacks. Taken together, our findings indicate that hissing calls can deter predator attacks and potentially increase survival rates of nesting great tits or their offspring, or both. The propensity to give hissing calls may be related to personality type of incubating female great tits, which needs to be tested experimentally.     

Information on Resource Quality Mediates Aggression between Male Madagascar Hissing Cockroaches, Gromphadorhina portentosa (Dictyoptera: Blaberidae)

Male Madagascar hissing cockroaches, Gromphadorhina portentosa Schaum (Dictyoptera: Blaberidae) have a well‐defined dominance hierarchy that has been assumed to explain the outcome of most competitive interactions. We studied whether males of this species would alter their level of aggression towards unfamiliar rivals as a function of changing resource availability and value – two factors that are key to aggression levels in non‐hierarchical species. We quantified male aggression as three variables (aggressive state – behaviours measured by their duration; aggressive act – behaviours measured by their frequency of occurrence; aggressive latency – the latency to first aggressive behaviour, either state or act) and tested for any context‐specific variation within each by manipulating both territorial status (males were either residents or intruders) and access to mates (female present or absent). Both the presence of a female and territorial status affected male aggression towards rivals as measured by duration of aggressive state. Highest levels of aggression were displayed by residents when a female was present. These results show that inter‐male aggression in G. portentosa is tuned to the immediate expected payoff from fighting, and not exclusively aimed at establishing dominance relationships (which can affect future payoffs).     

Utilizing Saccharomyces in the classroom: a versatile organism for teaching and learning

In the world of higher education, one of the struggles instructors face in the classroom is engaging students in the material. A second discussion in higher education pedagogy is how to weigh content versus activity in the science classroom. How should college teaching be set up when students now have every fact ever found at their fingertips on a device no larger than a half sandwich? What is the correct balance in the classroom between content/ knowledge and activity? As instructors grapple with these questions, a new type of learning experience called the Course Based Undergraduate Research Experience (CURE) has been developed, whereby students engage in an authentic research question in a classroom and laboratory setting. CUREs have been shown to be effective learning experiences for students but can be difficult to implement. Saccharomyces cerevisiae is a versatile and easy to use organism in the classroom that can be used for a wide variety of classroom activities. Described herein are a number of ways an instructor can use yeast in the classroom for authentic research experiences, especially focused towards a CURE.     

运用《生物化学》歌曲，辅助《生物化学》教学

《生物化学》以生物体为对象,研究其生命的化学本质,是生命科学领域的核心课程。长期以来,由于生物化学课程知识点多、范围广和内容抽象,在一定程度上会影响学生学习的自信心,压抑其学习过程中的兴趣,致使学习的积极性不高。最近10～20年里,国外将科学（science）、技术学（technology）、工程学（engineering）及数学（mathematics）的教育与艺术学（arts）,特别是与艺术学中的音乐结合实施教学,形成一种所谓的STEAM (STEM + Arts) 策略,对STEM教育进行辅助,取得了不错的效果。基于以上情况,结合国内生物化学教学实际,笔者尝试将生物化学歌曲应用于课堂教学过程中,辅助教学。生物化学歌曲可以将抽象难懂的生物化学知识转变成悦耳动听的歌曲,在教学过程中能激发学生的学习兴趣,活跃课堂气氛,使学生在学习过程中爱上生物化学;在生物化学歌曲的创作过程中,能促进学生的思考创新,内化重点难点,使深奥的问题形象化;在学习过程中用歌声展现生物化学的魅力,让知识成为有趣的知识,让其成为有趣的学习者。本文介绍了国内生物化学歌曲发展壮大历程,结合具体实例从利用生物化学歌曲引入教学、理解生物化学内容、密切联系生活三方面评论了生物化学歌曲在辅助生物化学教学中的应用,并从歌词的改编、旋律的选择、歌曲的传唱、教学的设计等方面需要注意的问题进行讨论。     

Variation and repeatability of male agonistic hiss characteristics and their relationship to social rank in Gromphadorhina portentosa

Male Madagascar hissing cockroaches, Gromphadorhina portentosa, produce a variety of sounds or ‘hisses’ during social interactions. The agonistic signals produced during male-male competition were examined, specifically the intra- and inter-individual variation of agonistic hisses, to determine if these sounds could be reliable indicators of male rank or male size. The relationship between characteristics of the agonistic hiss and social rank were also examined. Among males, agonistic hisses ranged from sounds without clear frequency bands to those with frequency modulation. Agonistic hisses varied in dominant frequency, which was measured at the beginning, middle, and end of the hiss, duration, and hiss rate (number per min). With males, the characteristics of a hiss were repeatable within and between days. Dominant males hissed significantly more than middle-ranking or subordinate males. While dominant, middle-ranking and subordinate males differed in the rate of hissing, there were no significant differences in the duration or dominant frequency of their hisses. Finally, the relationship between male weight and features of agonistic hisses was examined. Both duration and frequency were significantly correlated with male weight. Larger males had longer, lower frequency hisses than smaller males. The possible function of agonistic hissing during male-male interactions and the role of hisses in discrimination between individuals is discussed.