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1.
Sympatric speciation and radiative evolution of socially parasitic ants - Heretic hypotheses and their factual background 总被引:2,自引:0,他引:2
A. Buschinger 《Journal of Zoological Systematics and Evolutionary Research》1990,28(4):241-260
According to current hypotheses the main types of social parasitism among ants, namely slavery, temporary parasitism, and inquilinism, arose from such features as predation on other ants, or territorial behavior, both presumed precursors of slavemaking, and polygyny, a presumed precursor of temporary parasitism and inquilinism. The latter is believed also to represent a final instar in several evolutionary pathways leading from slavery, temporary parasitism, and xenobiosis to this permanently parasitic, workerless condition. Speciation, the origin of parasitic species from their usually closely related host species, is suggested to occur due to temporary geographic isolation and subsequent transition of one of the newly formed daughter species to parasitism in the nests of the other. Evidence is presented suggesting that the main types of social parasitism originated independently of each other. 15 ant genera are parasitized exclusively by inquilines, Eve other genera exclusively by temporary parasites. Only four groups of non-parasitic ant species (Formica, Tet-ramorium, Leptothorax subgenera Leptothorax and Myrafant) have parasites of several types each. Within these roups, however, there is little evidence of evolutionary transitions from one type to another. The few exceptions, mainly workerless species of the genera Epimyrma and Chalepoxenus, represent parasites which clearly derive from slave-making congeners, but differ from ordinary inquilines in that they eliminate the host colony queens like their actively dulotic ancestors. The new hypothesis suggests that all forms of interspecific true social parasitism (excluding xenobiosis) orginated from a common “preparasitic” stage, a subpopulation of reproductives in polygynous colonies and species, with diverging sexual behavior (near-nest mating vs. swarming) and caste ratios (production of more sexuals vs. workers). Arguments for sympatric speciation are compiled. Various features of the ancestral, and then host species (colony sizes, population density and structure, transition from polygyny to monoyny, etc.), and of the “preparasite” (production of few, or no workers, etc.) may shape the developing parasite to become a slave-maker, inquiline, or temporary parasite. These features usually leave open only one, or in a few genera, several options. The different types of parasitism within one host species group thus may have developed in a radiative manner from the common, preparasitic stage, which explains that independent colony foundation is a common feature of all true social parasites among ants. 相似文献
2.
Maxime Eeraerts 《Journal of Applied Entomology》2020,144(8):751-754
Mason bees (Osmia spp.) are receiving increasing attention as they are very effective pollinators of multiple crops. However, different bee-associated kleptoparasites are known which can be detrimental to the development of the bees’ offspring. To date, clear evidence-based guidelines to control these kleptoparasites are lacking for growers. This study investigates whether different types of artificial nesting materials—cardboard tubes and wooden grooved boards—influence the development of the European orchard bee (Osmia cornuta) as well as the infestation rate of kleptoparasitic mites in the bees’ nest. This preliminary study provides insight that cardboard tubes reduce the infestation rate of mites by 81.8% and as such promote successful development of the European orchard bee by 15.5%. Using cardboard tubes over wooden grooved boards should be advised to growers as an effective management strategy to avoid infestation of kleptoparasitic mites and to enhance successful bee development. 相似文献
3.
Peter Döbbeler 《Mycological Progress》2006,5(1):32-40
During the last years, many randomly collected specimens of the corticolous hepatic Frullania dilatata (Jungermanniales) from Tuscany (Italy) were carefully screened for the presence of fungi. A heterogeneous assemblage of ten species of ascomycetes belonging to nine genera and five orders were found. Especially well represented are the Hypocreales with four species. Altogether, more than 100 fungal records are given. A key to the species is provided and the distinguishing characters are indicated including illustrations of ascospores. Most frequently found are Calonectria frullaniae (perianthicolous), which prevents normal capsule development and Bryocentria brongniartii (leaf-perforating). Hypobryon florentinum Döbbeler is described as new. Up to five different species may be found on the same host specimen. Features shared by most species are the formation of tiny perithecial ascomata, biotrophic parasitism, restriction to F. dilatata, and occupation of distinct and species-specific microniches. This is the first bryomycological investigation based on comprehensive material of one host species occurring in a small part of its geographical distribution area.Taxonomic novelties: Hypobryon florentinum Döbbeler, sp. nov. 相似文献
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Spatial distribution of ant workers and, notably their aggregation/segregation behaviour, is a key-element of the colony social
organization contributing to the efficiency of task performance and division of labour. In polymorphic species, specialized
worker castes notably differ in their intrinsic aggregation behaviour. In this context, knowing the preponderant role of minors
in brood care, we investigate how a stimulus such as brood can influence the spatial patterns of Pheidole pallidula worker castes. In a homogeneous area without brood, it was shown that minors display only a low level of aggregation while
majors form large clusters in the central area. Here we find out that these aggregation patterns of both minors and majors
can be deeply influenced by the presence of brood. For minors, it nucleates or enhances the formation of a large stable cluster.
Such high sensitivity of minors to brood stimuli fits well with their role as main brood tenders in the colony. For majors,
interattraction between individuals still remains the prevailing aggregation factor while brood strongly influences the localisation
of their cluster. We discuss how the balance between interattraction and sensitivity to environmental stimuli determines the
mobility of each worker castes and, consequently, the availability of minors and majors to participate in everyday colony
tasks. Moreover, we will evoke the functional value of majors’ cluster location close to the brood, namely with respect to
social regulation of the colony caste ratio.
Received 30 May 2005; revised 11 January 2006; accepted 13 January 2006. 相似文献
6.
Facultative joint colony founding by social insects (pleometrosis) provides an outstanding opportunity to analyze the costs
and benefits of sociality. Pleometrosis has been documented for a range of social insects, but most studies on the adaptive
benefits of this behavior are restricted to the Hymenoptera. In this study, we provide the first analysis of costs and benefits
associated with pleometrosis for Australian Dunatothrips, which form domiciles by glueing together phyllodes (leaves) of their Acacia host plant. In Dunatothrips aneurae, the distribution of foundress numbers per nest indicated that females formed associations non-randomly. Furthermore, average
group size was independent of both the number of foundresses on the host plant and the number of mature colonies, suggesting
that this behavior was not simply a response to limited availability of nesting sites. Although per capita reproduction declined
with increasing group size, we also identified two benefits of pleometrosis: (1) individual foundresses in groups had higher
survival than solitary foundresses during the brood development period, and (2) larger colony sizes resulting from pleometrosis
provided a benefit later in colony development, because a higher proportion of D. aneurae adults survived invasions by the kleptoparasite Xaniothrips mulga when colony size was larger. These results demonstrate that the reproductive costs of pleometrosis are at least partially
counterbalanced by survival benefits.
Received 4 April 2006; revised 9 September 2006; accepted 20 September 2006. 相似文献
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9.
Yun Guo Yuejun He Pan Wu Bangli Wu Yan Lin Minhong He Xu Han Tingting Xia Kaiping Shen Liling Kang Qiyu Tan Wenda Ren Yan Sun Qing Li 《Journal of Plant Ecology》2022,15(2):399
AM 真菌和枯落物互作下两种喀斯特植物种间竞争较种内竞争更能促进植物养分利用
枯落物是植物养分获取和土壤养分转化的关键载体。丛枝菌根(Arbuscular mycorrhizae, AM)对植物养分摄取的影响已被广泛认知。然而,在养分亏缺的喀斯特生境中,不同竞争方式的植物如何通过AM真菌和枯落物利用养分尚不清楚。本研究对两种喀斯特适生植物构树(Broussonetia papyrifera)和云贵鹅耳枥(Carpinus pubescens)进行种内竞争和种 间竞争种植处理,并通过幼套球 囊霉(Glomus etunicatum)接种或不接种处理,以及土壤中添加或不添加两物种叶片混合枯落物处理,测定了植物生物量以及氮、磷、钾浓度等指标,研究植物的生长和养分利用。研究结果表明,AM真菌对两种植物养分摄取影响不同,AM真菌显著提高了种内和种间竞争下构树的养分摄取量,但降低了云贵鹅耳枥的养分摄取量。种间竞争下接种AM真菌,枯落物添加促进了云贵鹅耳枥对氮的摄取,抑制了构树对氮的摄取。接种AM真菌和添加枯落物条件下,种间竞争的构树对氮、磷和钾的摄取量及云贵鹅耳枥对氮的摄取量均高于种内竞争;种间竞争下两物种养分竞争力呈现明显差异,即构树对磷和钾养分竞争力显著提高,对氮则不显著;云贵鹅耳枥仅对钾的养分竞争力显著降低,对氮和磷则无显著影响。这些结果说明,在AM真菌与枯落物相互作用下,两种喀斯特植物种间竞争较种内竞争更能促进植物养分利用。 相似文献
10.
Abstract. A study was undertaken to assess the impact of the strepsipteran endoparasite Stichotrema dallatorreanum Hofeneder on the performance of its host Segestidea novaeguineae (Brancsik), a tettigoniid pest of oil palm in Papua New Guinea. This involved analyses of morphology, gut contents, body composition and reproductive variables of field-collected adults of stylopized and unstylopized hosts. The morphological consequences of stylopization by S. dallatorreanum included reduced wing, ovipositor and digestive tract lengths, whereas antennal length was largely unaffected. Feeding activity by the host, as estimated indirectly through weighing gut contents, was significantly reduced in parasitised female hosts, whereas smaller males showed no effect. Parasitized hosts had a reduced carcass dry weight associated with reduced nitrogen content and a substantial decline in carcass lipid content. Host reproductive variables were profoundly affected by stylopization. In females this included impaired ovarian development, reduced egg number and gonadal weight, the last of which was also reduced in males. There was an association between the number of S. dallatorreanum present (maximally six in males and nine in females) within a host and the extent of the impact of stylopization on most of the host characters investigated. The ability of S. dallatorreanum to reduce feeding and reproduction in the host suggests it may have potential use as a bio-control agent in the management of tettigoniid pests in Papua New Guinea. 相似文献