There exists a plethora of frameworks for classifying behaviour change interventions but an informal analysis suggests that none are comprehensive and conceptually coherent. For example, 'MINDSPACE' an influential report from the UK's Institute of Government, is intended as a checklist for policymakers of the most important influences on behaviour [11]. These influences provide initial letters for the acronym MINDSPACE: messenger, incentives, norms, defaults, salience, priming, affect, commitment, and ego. The framework does not appear to encompass all the important intervention types. Moreover, the list is a mixture of modes of delivery (e.g., messenger), stimulus attributes (e.g., salience), characteristics of the recipient (e.g., ego), policy strategies (e.g., defaults), mechanisms of action (e.g., priming), and related psychological constructs (e.g., affect). In that sense it lacks coherence. The report recognises two systems by which human behaviour can be influenced -- the reflective and the automatic -- but it focuses on the latter and does not attempt to link influences on behaviour with these two systems.
The list of organisms by chromosome count describes ploidy or numbers of chromosomes in the cells of various plants, animals, protists, and other living organisms. This number, along with the visual appearance of the chromosome, is known as the karyotype,[1][2][3] and can be found by looking at the chromosomes through a microscope. Attention is paid to their length, the position of the centromeres, banding pattern, any differences between the sex chromosomes, and any other physical characteristics.[4] The preparation and study of karyotypes is part of cytogenetics.
Tarantula Species List With Pictures Pdf 42
Wolbachia are a group of maternally inherited bacteria that infect a wide range of arthropods. Wolbachia infections are known to result in the expression of various abnormal reproductive phenotypes, the best known being cytoplasmic incompatibility. The first systematic survey of 42 spider mite species in Japan revealed that seven species (16.7%) were infected with Wolbachia. Wolbachia in the spider mites were grouped into three subgroups in supergroup B by phylogenetic analyses of the wsp gene. Most spider mites did not show cytoplasmic incompatibility when infected males were crossed with uninfected females. However, all infected populations of Panonychus mori and Oligonychus gotohi (five and four populations, respectively) possessed modification-positive strains of Wolbachia, and the cytoplasmic incompatibility decreased egg hatchability and female ratio of the spider mites. Thus, some Wolbachia strains cause sex ratio distortion in their hosts.
Wolbachia are alpha proteobacteria that infect a wide range of arthropods (Werren et al, 1995a; Jeyaprakash and Hoy, 2000) and filarial nematodes (Bandi et al, 1998). Wolbachia infect at least 16.9% of neotropic insects (Werren et al, 1995a), and 19.3% of temperate insect species sampled in North America (Werren and Windsor, 2000). Wolbachia infection is very common in some insect groups. For instance, 50% of a sample of 50 Indonesian ant species (Wenseleers et al, 1998) and 28.1% of 89 wild-caught mosquito species in Southeast Asia (Kittayapong et al, 2000) are infected with Wolbachia. Other invertebrates besides insects are commonly infected with Wolbachia. A total of 22 out of 85 (26%) species of isopod crustaceans (Bouchon et al, 1998) and nine of 10 species of filarial nematodes were found to be infected with Wolbachia (Bandi et al, 1998). However, none of the mollusk species tested were infected (Schilthuizen and Gittenberger, 1998). Wolbachia were subdivided into six supergroups from A to F (Lo et al, 2002) based on the ftsZ gene sequence (Werren et al, 1995b). Arthropods are mainly infected with Wolbachia belonging to supergroups A and B, nematodes are infected with supergroups C and D, springtail is infected with supergroup E (Vandekerchove et al, 1999) and termites are infected with supergroup F (Lo et al, 2002).
Five out of 52 populations of P. mori were infected with Wolbachia. However, Wolbachia were not found in 72 populations of P. citri or in 44 populations of P. osmanthi. Two populations in Schizotetranychus cercidiphylli possessed Wolbachia. Both the chestnut and Pasania populations of Oligonychus gotohi were infected with Wolbachia. The infection frequencies of two closely related species, T. kanzawai and T. parakanzawai, were similar (29.3 and 31.3%, respectively). Previously, 14 out of 63 populations of T. kanzawai and four out of 11 populations of T. parakanzawai were found to be infected with Wolbachia (Gotoh et al, 1999a; in this paper, T. kanzawai and T. parakanzawai were referred to as the T and K strains of T. kanzawai, respectively). In the present study, we included an additional eight infected populations of T. kanzawai and one additional infected population of T. parakanzawai. We detected Wolbachia in two of three populations of the green form of T. urticae, one of which was reported previously (Gotoh et al, 1999b). On the contrary, we failed to detect Wolbachia in six populations of the red form of T. urticae. Out of 38 populations of T. pueraricola, which morphologically resembles T. urticae, 18 were infected with Wolbachia. Thus, 59 (16.3%) of the 362 populations examined were infected with Wolbachia.
In our survey of 42 species and 362 populations of spider mites from Japan, the frequency of infected species was 16.7% (seven of 42 species). For most species (36/42), we tested more than 10 individuals for Wolbachia infection. Similar frequencies of infection have been reported for other arthropods (eg Werren et al, 1995a (16.9%); West et al, 1998 (21.7%); Werren and Windsor, 2000 (19.3%); Jiggins et al, 2001 (16.7%)). However, Breeuwer and Jacobs (1996) detected Wolbachia in six out of 16 species (37.5%). Among mites of the genus Tetranychus, they detected Wolbachia in four out of 12 species (33.3%). We also detected Wolbachia at a high rate (40%; 4/10) in the genus Tetranychus. Our data revealed that the infection rate in genera other than Tetranychus was low (9.4%; 3/32). Wolbachia was unequally distributed among the genera of the spider mites. No Wolbachia infection was found in Aponychus, Sasanychus, Yezonychus, Eotetranychus or Amphitetranychus, although the number of the test species in these genera is not sufficient to say that these genera are Wolbachia free. Unequal distributions were also observed within a single genus. For example, we did not find Wolbachia in P. citri or P. osmanthi, even though 72 populations of the former and 44 populations of the latter were tested. Only one species of Panonychus, P. mori, was infected with Wolbachia.
The phylogenetic analysis of wsp genes revealed that Wolbachia in the spider mites in Japan belong to the subgroups Ori, Con and Epo in the supergroup B (Figure 2). The Ori and Con subgroups were first proposed by Zhou et al (1998) based on the wsp gene phylogeny. Zhou et al (1998) proposed that members of any subgroup should have a similarity in the wsp sequence greater than 97.5%. Therefore, we now propose a new subgroup, the Epo subgroup, named after the host species Acraea eponina (accession number AJ271194), which was the first member of this subgroup to be deposited in the database. The Wolbachia strains in O. gotohi belong to the subgroup Epo, and are distantly related to other Wolbachia strains in spider mites. Wolbachia in S. cercidiphylli belongs to the subgroup Con, and the strains in T. urticae including the European populations belong to the subgroup Ori. Wolbachia in the other four species among the populations were separated into the subgroups Con and Ori. These results suggest that Wolbachia in the spider mites originated from a few or several ancestral strains and have been inherited for many generations of the spider mites. As has been pointed out by many authors (eg Werren et al, 1995b; van Meer et al, 1999), acquisition of Wolbachia in the spider mites appears to be due to horizontal infection, because the phylogeny of Wolbachia is not concordant with that of the host species, and the same mite species had different Wolbachia strains. Identical nucleotide sequences of wsp genes were detected in eight populations from three species in the subgroup Ori, suggesting recent horizontal transmission of Wolbachia among the spider mites. As was pointed out by Jiggins et al (2002), Wolbachia are more likely to move horizontally within the host groups than between distantly related hosts. Horizontal transmission is considered to be caused by parasites or parasitoids (Heath et al, 1999; Huigens et al, 2000; Noda et al, 2001b), but it is unknown how the bacteria have spread among the spider mites.
An important result of the phylogenetic tree is that the same species possess the same strain or a very close strain of Wolbachia despite the location of the host mites. Closely related strains of Wolbachia were found in T. urticae of the European and Japanese populations. Based on the wsp gene sequences, the same Wolbachia strain was detected in the Sendai, Toyama and Hanayama populations of P. mori. These observations indicate that different species of spider mites are associated with specific strains of Wolbachia. One possible explanation of this phenomenon is that the relationship between the mites and Wolbachia is old and Wolbachia have been inherited from many generations in the same species. This means Wolbachia have spread geographically through the parasite population. Another possible explanation is that the infection comes from parasites of spider mites, because Wolbachia-infected populations distribute patchily and do not show any continuous distribution even on cultivated crops, which is different from the continuous distribution caused by spreading of Drosophila simulans (Turelli and Hoffmann, 1991) or Laodelphax striatellus (Noda et al, 2001b). That is, a parasite that is specific to a given species of spider mite might carry a specific strain of Wolbachia. However, the latter explanation needs further evidence that similar parasites with the same Wolbachia strain attack the spider mites in Japan and Europe. Wolbachia is distributed among the spider mites by horizontal and vertical transmissions, although it is hard to fully explain how this transmission occurs.
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