Extrinsic Inter- and Intra-specific Competition in Parasitoid Wasps

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Paul J. Ode ◽  
Dhaval K. Vyas ◽  
Jeffrey A. Harvey

The diverse ecology of parasitoids is shaped by extrinsic competition, i.e., exploitative or interference competition among adult females and males for hosts and mates. Adult females use an array of morphological, chemical, and behavioral mechanisms to engage in competition that may be either intra- or interspecific. Weaker competitors are often excluded or, if they persist, use alternate host habitats, host developmental stages, or host species. Competition among adult males for mates is almost exclusively intraspecific and involves visual displays, chemical signals, and even physical combat. Extrinsic competition influences community structure through its role in competitive displacement and apparent competition. Finally, anthropogenic changes such as habitat loss and fragmentation, invasive species, pollutants, and climate change result in phenological mismatches and range expansions within host–parasitoid communities with consequent changes to the strength of competitive interactions. Such changes have important ramifications not only for the success of managed agroecosystems, but also for natural ecosystem functioning. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Hassan Salem ◽  
Martin Kaltenpoth

Beetles are hosts to a remarkable diversity of bacterial symbionts. In this article, we review the role of these partnerships in promoting beetle fitness following a surge of recent studies characterizing symbiont localization and function across the Coleoptera. Symbiont contributions range from the supplementation of essential nutrients and digestive or detoxifying enzymes to the production of bioactive compounds providing defense against natural enemies. Insights on this functional diversity highlight how symbiosis can expand the host's ecological niche, but also constrain its evolutionary potential by promoting specialization. As bacterial localization can differ within and between beetle clades, we discuss how it corresponds to the microbe's beneficial role and outline the molecular and behavioral mechanisms underlying symbiont translocation and transmission by its holometabolous host. In reviewing this literature, we emphasize how the study of symbiosis can inform our understanding of the phenotypic innovations behind the evolutionary success of beetles. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Sara Zarghami ◽  
Mohammad Saeed Mossadegh ◽  
Farhan Kocheili ◽  
Hossein Allahyari ◽  
Arash Rasekh

Nephus arcuatusKapur is an important predator ofNipaecoccus viridis(Newstead), in citrus orchards of southwestern Iran. This study examined the feeding efficiency of all stages ofN. arcuatusat different densities ofN. viridiseggs by estimating their functional responses. First and 2nd instar larvae as well as adult males exhibited a type II functional response. Attack rate and handling time were estimated to be 0.2749 h−1and 5.4252 h, respectively, for 1st instars, 0.5142 h−1and 1.1995 h for 2nd instars, and 0.4726 h−1and 0.7765 h for adult males. In contrast, 3rd and 4th instar larvae and adult females ofN. arcuatusexhibited a type III functional response. Constantband handling time were estimated to be 0.0142 and 0.4064 h for 3rd instars, respectively, 0.00660 and 0.1492 h for 4th instars, and 0.00859 and 0.2850 h for adult females. The functional response of these six developmental stages differed in handling time. Based on maximum predation rate, 4th instar larvae were the most predatory (160.9 eggs/d) followed by adult females (84.2 eggs/d). These findings suggest thatN. arcuatusis a promising biocontrol agent ofN. viridiseggs especially for 4th instar larvae and adult females.


Author(s):  
Elliott S. Chiu ◽  
Sue VandeWoude

Endogenous retroviruses (ERVs) serve as markers of ancient viral infections and provide invaluable insight into host and viral evolution. ERVs have been exapted to assist in performing basic biological functions, including placentation, immune modulation, and oncogenesis. A subset of ERVs share high nucleotide similarity to circulating horizontally transmitted exogenous retrovirus (XRV) progenitors. In these cases, ERV–XRV interactions have been documented and include ( a) recombination to result in ERV–XRV chimeras, ( b) ERV induction of immune self-tolerance to XRV antigens, ( c) ERV antigen interference with XRV receptor binding, and ( d) interactions resulting in both enhancement and restriction of XRV infections. Whereas the mechanisms governing recombination and immune self-tolerance have been partially determined, enhancement and restriction of XRV infection are virus specific and only partially understood. This review summarizes interactions between six unique ERV–XRV pairs, highlighting important ERV biological functions and potential evolutionary histories in vertebrate hosts. Expected final online publication date for the Annual Review of Animal Biosciences, Volume 9 is February 16, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


Zootaxa ◽  
2011 ◽  
Vol 2983 (1) ◽  
pp. 39 ◽  
Author(s):  
IVAN L. F. MAGALHÃES ◽  
ADALBERTO J. SANTOS

In this paper, M. yanomami n. sp., from Brazilian Amazonia, Chaetacis bandeirante n. sp., from Central Brazil, and the males of M. gaujoni Simon, 1897 and M. ruschii (Mello-Leitão, 1945) n. comb. , respectively from Ecuador and Brazil, are described and illustrated for the first time. An ontogenetic series of the last development stages of both sexes of Micrathena excavata (C. L. Koch, 1836) is illustrated and briefly described. Adult females are larger and have longer legs and larger abdomens than adult males. Probably females undergo at least one additional moult before adulthood, compared to males. Micrathena ornata Mello-Leitão, 1932 is considered a junior synonym of M. plana (C. L. Koch, 1836), and M. mastonota Mello-Leitão 1940 is synonymized with M. horrida (Taczanowski, 1873). Acrosoma ruschii Mello-Leitão, 1945 is revalidated, transferred to Micrathena and considered a senior synonym of M. cicuta Gonzaga & Santos, 2004. Chaetacis necopinata (Chickering, 1960) is recorded for Brazil for the first time. Chaetacis incisa (Walckenaer, 1841) is considered a nomen dubium.


1994 ◽  
Vol 72 (7) ◽  
pp. 1314-1324 ◽  
Author(s):  
D. G. Reid ◽  
T. E. Code ◽  
A. C. H. Reid ◽  
S. M. Herrero

Seasonal spacing patterns, home ranges, and movements of river otters (Lontra canadensis) were studied in boreal Alberta by means of radiotelemetry. Adult males occupied significantly larger annual home ranges than adult females. Males' ranges overlapped those of females and also each other's. In winter, home ranges of males shrank and showed less overlap. Otters often associated in groups, the core members typically being adult females with young, or adult males. Otters tended to be more solitary in winter. In winter, movement rates of all sex and age classes were similar, and much reduced for males compared with those in other seasons. These data indicated a strong limiting effect of winter ice on behaviour and dispersion. We tested the hypothesis that otters select water bodies in winter on the basis of the suitability of shoreline substrate and morphology for dens with access both to air and to water under ice. Intensity of selection was greatest in winter, with avoidance of gradually sloping shorelines of sand or gravel. Adults selected bog lakes with banked shores containing semi-aquatic mammal burrows, and lakes with beaver lodges. Subadults selected beaver-impounded streams. Apart from human harvest, winter habitats and food availability in such habitats are likely the two factors most strongly limiting otter density in boreal Alberta.


Behaviour ◽  
1980 ◽  
Vol 72 (1-2) ◽  
pp. 26-48 ◽  
Author(s):  
Patrick Duncan

AbstractTime-budgets of adult and weaned sub-adult horses were studied in a small population of Camargue horses living in semi-liberty. The categories of activities used were: Standing resting, Lying flat, Lying up, Standing alert, Walking, Trotting, Galloping, Rolling and Foraging. The main differences in time-budgets were related to age and to sex : young horses spent more time lying (sleeping), males spent more time standing alert and in rapid movements (trot, gallop), while usually foraging less than did the adult females. During the three years of the study the population increased from 20 to 54 horses and there were considerable changes in social structure as the number of adult males increased. Associated with these developments there were some changes between years in the time-budgets: the most striking of which was a general trend for all horses to spend less time lying. Nonetheless the time-budgets showed a considerable constancy across years and age/sex-classes, especially with regard to time spent foraging. This conclusion may provide a clue as to why horses have an unusual social system based on long term relationships between a male and the females of his harem.


Author(s):  
Sarah Knuckey ◽  
Joshua D. Fisher ◽  
Amanda M. Klasing ◽  
Tess Russo ◽  
Margaret L. Satterthwaite

The human rights movement is increasingly using interdisciplinary, multidisciplinary, mixed-methods, and quantitative factfinding. There has been too little analysis of these shifts. This article examines some of the opportunities and challenges of these methods, focusing on the investigation of socioeconomic human rights. By potentially expanding the amount and types of evidence available, factfinding's accuracy and persuasiveness can be strengthened, bolstering rights claims. However, such methods can also present significant challenges and may pose risks in individual cases and to the human rights movement generally. Interdisciplinary methods can be costly in human, financial, and technical resources; are sometimes challenging to implement; may divert limited resources from other work; can reify inequalities; may produce “expertise” that disempowers rightsholders; and could raise investigation standards to an infeasible or counterproductive level. This article includes lessons learned and questions to guide researchers and human rights advocates considering mixed-methods human rights factfinding. Expected final online publication date for the Annual Review of Law and Social Science, Volume 17 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


2021 ◽  
Vol 50 (1) ◽  
Author(s):  
Simeon Floyd

Conversation analysis is a method for the systematic study of interaction in terms of a sequential turn-taking system. Research in conversation analysis has traditionally focused on speakers of English, and it is still unclear to what extent the system observed in that research applies to conversation more generally around the world. However, as this method is now being applied to conversation in a broader range of languages, it is increasingly possible to address questions about the nature of interactional diversity across different speech communities. The approach of pragmatic typology first applies sequential analysis to conversation from different speech communities and then compares interactional patterns in ways analogous to how traditional linguistic typology compares morphosyntax. This article discusses contemporary literature in pragmatic typology, including single-language studies and multilanguage comparisons reflecting both qualitative and quantitative methods. This research finds that microanalysis of face-to-face interaction can identify both universal trends and culture-specific interactional tendencies. Expected final online publication date for the Annual Review of Anthropology, Volume 50 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


Author(s):  
Yonit Maroudas-Sacks ◽  
Kinneret Keren

Morphogenesis is one of the most remarkable examples of biological pattern formation. Despite substantial progress in the field, we still do not understand the organizational principles responsible for the robust convergence of the morphogenesis process across scales to form viable organisms under variable conditions. Achieving large-scale coordination requires feedback between mechanical and biochemical processes, spanning all levels of organization and relating the emerging patterns with the mechanisms driving their formation. In this review, we highlight the role of mechanics in the patterning process, emphasizing the active and synergistic manner in which mechanical processes participate in developmental patterning rather than merely following a program set by biochemical signals. We discuss the value of applying a coarse-grained approach toward understanding this complex interplay, which considers the large-scale dynamics and feedback as well as complementing the reductionist approach focused on molecular detail. A central challenge in this approach is identifying relevant coarse-grained variables and developing effective theories that can serve as a basis for an integrated framework for understanding this remarkable pattern-formation process. Expected final online publication date for the Annual Review of Cell and Developmental Biology, Volume 37 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Kristen Kobaly ◽  
Caroline S. Kim ◽  
Susan J. Mandel

Thyroid nodules are common in the general population, with higher prevalence in women and with advancing age. Approximately 5% of thyroid nodules are malignant; the majority of this subset represents papillary thyroid cancer. Ultrasonography is the standard technique to assess the underlying thyroid parenchyma, characterize the features of thyroid nodules, and evaluate for abnormal cervical lymphadenopathy. Various risk stratification systems exist to categorize the risk of malignancy based on the ultrasound appearance of a thyroid nodule. Nodules are selected for fine-needle aspiration biopsy on the basis of ultrasound features, size, and high-risk clinical history. Cytology results are classified by the Bethesda system into six categories ranging from benign to malignant. When cytology is indeterminate, molecular testing can further risk-stratify patients for observation or surgery. Surveillance is indicated for nodules with benign cytology, indeterminate cytology with reassuring molecular testing, or non-biopsied nodules without a benign sonographic appearance. Expected final online publication date for the Annual Review of Medicine, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


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