Evolution of sociality by natural selection on variances in reproductive fitness: evidence from a social bee

Background The Central Limit Theorem (CLT) is a statistical principle that states that as the number of repeated samples from any population increase, the variance among sample means will decrease and means will become more normally distributed. It has been conjectured that the CLT has the potential to provide benefits for group living in some animals via greater predictability in food acquisition, if the number of foraging bouts increases with group size. The potential existence of benefits for group living derived from a purely statistical principle is highly intriguing and it has implications for the origins of sociality. Results Here we show that in a social allodapine bee the relationship between cumulative food acquisition (measured as total brood weight) and colony size accords with the CLT. We show that deviations from expected food income decrease with group size, and that brood weights become more normally distributed both over time and with increasing colony size, as predicted by the CLT. Larger colonies are better able to match egg production to expected food intake, and better able to avoid costs associated with producing more brood than can be reared while reducing the risk of under-exploiting the food resources that may be available. Conclusion These benefits to group living derive from a purely statistical principle, rather than from ecological, ergonomic or genetic factors, and could apply to a wide variety of species. This in turn suggests that the CLT may provide benefits at the early evolutionary stages of sociality and that evolution of group size could result from selection on variances in reproductive fitness. In addition, they may help explain why sociality has evolved in some groups and not others

Evolution of sociality by natural selection on variances in reproductive fitness: evidence from a social bee

<p>Abstract</p> <p>Background</p> <p>The Central Limit Theorem (CLT) is a statistical principle that states that as the number of repeated samples from any population increase, the variance among sample means will decrease and means will become more normally distributed. It has been conjectured that the CLT has the potential to provide benefits for group living in some animals via greater predictability in food acquisition, if the number of foraging bouts increases with group size. The potential existence of benefits for group living derived from a purely statistical principle is highly intriguing and it has implications for the origins of sociality.</p> <p>Results</p> <p>Here we show that in a social allodapine bee the relationship between cumulative food acquisition (measured as total brood weight) and colony size accords with the CLT. We show that deviations from expected food income decrease with group size, and that brood weights become more normally distributed both over time and with increasing colony size, as predicted by the CLT. Larger colonies are better able to match egg production to expected food intake, and better able to avoid costs associated with producing more brood than can be reared while reducing the risk of under-exploiting the food resources that may be available.</p> <p>Conclusion</p> <p>These benefits to group living derive from a purely statistical principle, rather than from ecological, ergonomic or genetic factors, and could apply to a wide variety of species. This in turn suggests that the CLT may provide benefits at the early evolutionary stages of sociality and that evolution of group size could result from selection on variances in reproductive fitness. In addition, they may help explain why sociality has evolved in some groups and not others.</p

The effect of protective covers on pollinator health and pollination service delivery

Protective covers (i.e., glasshouses, netting enclosures, and polytunnels) are increasingly used in crop production to enhance crop quality, yield, and production efficiency. However, many protected crops require insect pollinators to achieve optimal pollination and there is no consensus about how best to manage pollinators and crop pollination in these environments. We conducted a systematic literature review to synthesise knowledge about the effect of protective covers on pollinator health and pollination services and identified 290 relevant studies. Bees were the dominant taxon used in protected systems (90%), represented by eusocial bees (e.g., bumble bees (Bombus spp.), honey bees (Apis spp.), stingless bees (Apidae: Meliponini)) and solitary bees (e.g., Amegilla spp., Megachile spp., and Osmia spp.). Flies represented 9% of taxa and included Calliphoridae, Muscidae, and Syrphidae. The remaining 1% of taxa was represented by Lepidoptera and Coleoptera. Of the studies that assessed pollination services, 96% indicate that pollinators were active on the crop and/or their visits resulted in improved fruit production compared with flowers not visited by insects (i.e., insect visits prevented, or flowers were self- or mechanically pollinated). Only 20% of studies evaluated pollinator health. Some taxa, such as mason or leafcutter bees, and bumble bees can function well in covered environments, but the effect of covers on pollinator health was negative in over 50% of the studies in which health was assessed. Negative effects included decreased reproduction, adult mortality, reduced forager activity, and increased disease prevalence. These effects may have occurred as a result of changes in temperature/humidity, light quality/quantity, pesticide exposure, and/or reduced access to food resources. Strategies reported to successfully enhance pollinator health and efficiency in covered systems include: careful selection of bee hive location to reduce heat stress and improve dispersal through the crop; increased floral diversity; deploying appropriate numbers of pollinators; and manipulation of flower physiology to increase attractiveness to pollinating insects. To improve and safeguard crop yields in pollinator dependent protected cropping systems, practitioners need to ensure that delivery of crop pollination services is compatible with suitable conditions for pollinator health

Evolution of Blind Beetles in Isolated Aquifers: A Test of Alternative Modes of Speciation

Evidence is growing that not only allopatric but also sympatric speciation can be important in the evolution of species. Sympatric speciation has most convincingly been demonstrated in laboratory experiments with bacteria, but field-based evidence is limited to a few cases. The recently discovered plethora of subterranean diving beetle species in isolated aquifers in the arid interior of Australia offers a unique opportunity to evaluate alternative modes of speciation. This naturally replicated evolutionary experiment started 10-5 million years ago, when climate change forced the surface species to occupy geographically isolated subterranean aquifers. Using phylogenetic analysis, we determine the frequency of aquifers containing closely related sister species. By comparing observed frequencies with predictions from different statistical models, we show that it is very unlikely that the high number of sympatrically occurring sister species can be explained by a combination of allopatric evolution and repeated colonisations alone. Thus, diversification has occurred within the aquifers and likely involved sympatric, parapatric and/or microallopatric speciation

The Youth Anxiety Measure for DSM-5 (YAM-5):Development and First Psychometric Evidence of a New Scale for Assessing Anxiety Disorders Symptoms of Children and Adolescents

The Youth Anxiety Measure for DSM-5 (YAM-5) is a new self- and parent-report questionnaire to assess anxiety disorder symptoms in children and adolescents in terms of the contemporary classification system. International panels of childhood anxiety researchers and clinicians were used to construct a scale consisting of two parts: part one consists of 28 items and measures the major anxiety disorders including separation anxiety disorder, selective mutism, social anxiety disorder, panic disorder, and generalized anxiety disorder, whereas part two contains 22 items that focus on specific phobias and (given its overlap with situational phobias) agoraphobia. In general, the face validity of the new scale was good; most of its items were successfully linked to the intended anxiety disorders. Notable exceptions were the selective mutism items, which were frequently considered as symptoms of social anxiety disorder, and some specific phobia items especially of the natural environment, situational and other type, that were regularly assigned to an incorrect category. A preliminary investigation of the YAM-5 in non-clinical (N = 132) and clinically referred (N = 64) children and adolescents indicated that the measure was easy to complete by youngsters. In addition, support was found for the psychometric qualities of the measure: that is, the internal consistency was good for both parts, as well as for most of the subscales, the parent-child agreement appeared satisfactory, and there was also evidence for the validity of the scale. The YAM-5 holds promise as a tool for assessing anxiety disorder symptoms in children and adolescents

Reading tea leaves worldwide: decoupled drivers of initial litter decomposition mass‐loss rate and stabilization

The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large‐scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass‐loss rates and stabilization factors of plant‐derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy‐to‐degrade components accumulate during early‐stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass‐loss rates and stabilization, notably in colder locations. Using TBI improved mass‐loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early‐stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models

New species of Goniocolletes and Trichocolletes (Hymenoptera, Colletidae) from southern Australia

Goniocolletes comatus Maynard, 2013 is redescribed. G. wanni sp. n. and the male of Trichocolletes luteorufus Batley & Houston, 2012 are described

Figure 20-21 from: Leijs R, Batley M, Hogendoorn K (2017) The genus Amegilla (Hymenoptera, Apidae, Anthophorini) in Australia: A revision of the subgenera Notomegilla and Zonamegilla. ZooKeys 653: 79-140. https://doi.org/10.3897/zookeys.653.11177

Figure 20-21 - S6 of males 20 Notomegilla 21 Zonamegilla

Twenty six new species of Leioproctus (Colletellus): Australian Neopasiphaeinae, all but one with two submarginal cells (Hymenoptera, Colletidae, Leioproctus)

Twenty six new species of Australian Leioproctus (subgenus Colletellus) (Hymenoptera, Colletidae) are described: aberrans Leijs, sp. n., alatus Leijs, sp. n., albipilosus Leijs, sp. n., albiscopis Leijs, sp. n., aliceafontanus Leijs, sp. n., altispinosus Leijs, sp. n., aratus Leijs, sp. n., auricorneus Leijs, sp. n., bidentatus Leijs, sp. n., centralis Leijs, sp. n., ciliatus Leijs, sp. n., claviger Leijs, sp. n., consobrinus Leijs, sp. n., constrictus Leijs, sp. n., laciniosus Leijs, sp. n., longivultu Leijs, sp. n., lucidus Leijs, sp. n., nitidifuscus Leijs, sp. n., pectinatus Leijs, sp. n., pilotapilus Leijs, sp. n., quadripinnatus Leijs, sp. n., rubicundus Leijs, sp. n., rubricinctus Leijs, sp. n., similis Leijs, sp. n., splendens Leijs, sp. n., submetallicus Leijs, sp. n. High resolution images of diagnostic characters for all type specimens are included. Identification keys are provided

Increased Tomato Yield Through Pollination by Native Australian 'Amegilla chlorocyanea' (hymenoptera: anthophoridae)

'Amegilla spp.' (Hymenoptera: Anthophoridae) have been suggested as potential native Australian alternative to overseas used bumblebees (Bombus spp.) for pollination of tomato in greenhouses. In this study, we investigate the effectiveness of 'Amegilla chlorocyanea' Cockerell as a greenhouse pollinator of tomato, Lycopersicon esculentum' Mill. We show that 1) a single buzz by a female increases tomato weight by 11% compared with pollination by using an industrial pollination wand, 2) multiple buzzes increase tomato weight compared with a single buzz, and 3) unlimited flower visits lead to an increase in fruit weight of 21% compared with wand pollination. These results are comparable with those achieved by bumblebee pollination and demonstrate that 'A. chlorocyanea' is a valid alternative to bumblebees for greenhouse tomato pollination in Australia