Reducing the Overlap Between Machiavellianism and Subclinical Psychopathy: The M7 and P7 Scales

Machiavellianism (Mach) and subclinical psychopathy are two widely studied antagonistic personality traits with distinct theoretical conceptualizations. Mach is conceptualized by strategic deviousness, cynicism, and pragmatic morality, whereas subclinical psychopathy is conceptualized by impulsive antisocial tendencies, callousness, and rule-breaking. However, existing measures of the two traits are typically highly correlated and have very similar nomological networks. Notably, even though psychopathy scales should be more strongly positively associated with antisocial impulsivity and more strongly negatively associated with conscientiousness than Mach scales, existing Mach and psychopathy scales tend to be similarly related to these constructs. We created a new Mach scale, the M7, and a new psychopathy scale, the P7, by selecting items from existing Mach and psychopathy scales on the basis of the correlations of these items with antisocial impulsivity and conscientiousness. Across three studies (combined N = 4,607), the M7 and P7 showed acceptable to good psychometric properties in terms of closeness to unidimensionality, measurement precision, temporal stability, measurement invariance across language and gender groups, and convergent and discriminant validity (nomological network, self-other agreement, and interpersonal perceptions in group interactions). Most importantly, the new scales assess clearly distinct latent traits that are more in line with their theoretical conceptualizations than established scales are

On the origin of the stellar halo and multiple stellar populations in the globular cluster NGC 1851

We propose that the observed stellar halo around the globular cluster (GC) NGC 1851 is evidence for its formation in the central region of its defunct host dwarf galaxy. We numerically investigate the long-term dynamical evolution of a nucleated dwarf galaxy embedded in a massive dark matter halo under the strong tidal field of the Galaxy. The dwarf galaxy is assumed to have a stellar nucleus (or a nuclear star cluster) that could be the progenitor for NGC 1851. We find that although the dark matter halo and the stellar envelope of the host dwarf of NGC 1851 can be almost completely stripped during its orbital evolution around the Galaxy, a minor fraction of stars in the dwarf can remain trapped by the gravitational field of the nucleus. The stripped nucleus can be observed as NGC 1851 with no/little dark matter whereas stars around the nucleus can be observed as a diffuse stellar halo around NGC 1851. The simulated stellar halo has a symmetric distribution with a power-law density slope of ~ -2 and shows no tidal tails within ~200pc from NGC 1851. We show that two GCs can merge with each other to form a new nuclear GC embedded in field stars owing to the low stellar velocity dispersion of the host dwarf. This result makes no assumption on the ages and/or chemical abundances of the two merging GCs. Thus the observed stellar halo and characteristic multiple stellar populations in NGC 1851 suggest that NGC 1851 could have formed initially in the central region of an ancient dwarf galaxy.Comment: 15 pages, 12 figures, accepted in MNRA

Consistent patterns of high alpha and low beta diversity in tropical parasitic and free-living protists

Tropical animals and plants are known to have high alpha diversity within forests, but low beta diversity between forests. By contrast, it is unknown if microbes inhabiting the same ecosystems exhibit similar biogeographic patterns. To evaluate the biogeographies of tropical protists, we used metabarcoding data of species sampled in the soils of three lowland Neotropical rainforests. Taxa-area and distance-decay relationships for three of the dominant protist taxa and their subtaxa were estimated at both the OTU- and hylogenetic-levels, with presence-absence and abundance based measures. These estimates were compared to null models. High local alpha and low regional beta diversity patterns were consistently found for both the parasitic Apicomplexa and the largely free-living Cercozoa and Ciliophora. Similar to animals and plants, the protists showed spatial structures between forests at the OTU- and phylogenetic-levels, and only at the phylogenetic level within forests. These results suggest that the biogeographies of macro- and micro-organismal eukaryotes in lowland Neotropical rainforests are partially structured by the same general processes. However, and unlike the animals and plants, the protist OTUs did not exhibit spatial structures within forests, which hinders our ability to estimate local and regional diversity of protists in tropical forests