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Excessive self-criticism is common to many mental health problems, including depression. Theoretically, positive self-compassion may work to prevent depression by protecting against the proliferation of self-condemning responses. A sample of Norwegian university students (N = 277, mean age = 22.9 years, SD = 3.5 years, 56% women) completed the Self-Compassion Scale (SCS) and the SCL-90 Depression subscale. Items of the three positive SCS-subscales (selfkindness, mindfulness, and common humanity) and items of the three negative SCS subscales (self-judgment, over-identification, and isolation) were combined to provide measures of Positive Self-Compassion and Self-Condemnation respectively. A moderation analysis indicated that the association between Self-Condemnation and Depressive Symptoms was weaker for individuals high in positive self-compassion, as expected. Bootstrap mediation analyses (conducted separately in groups scoring high and low in positive self-compassion) suggested that, in individuals high in positive self-compassion, self-compassion worked to reduce depressive symptoms by inversely affecting self-condemnation. When positive self-compassion was low, however, only Self-Condemnation predicted Depressive Symptoms. These results suggest that when positive self-compassion is above a certain level, it can keep self-condemning responses in check. If positive self-compassion is too weak, however, something else is needed, perhaps understanding input from another person. [ABSTRACT FROM AUTHOR]

Vocalizations often vary in structure within a species, from the individual to population level. Vocal differences among social groups and populations can provide insight into biological processes such as vocal learning and evolutionary divergence, with important conservation implications. As vocal learners of conservation concern, intraspecific vocal variation is of particular interest in elephants. We recorded calls from individuals in multiple, wild elephant social groups in two distinct Kenyan populations. We used machine learning to investigate vocal differentiation among individual callers, core groups, bond groups (collections of core groups) and populations. We found clear evidence for vocal distinctiveness at the individual and population level, and evidence for much subtler vocal differences among social groups. Social group membership was a better predictor of call similarity than genetic relatedness, suggesting that subtle vocal differences among social groups may be learned. Vocal divergence among populations and social groups has conservation implications for the effects of social disruption and translocation of elephants., Competing Interests: We declare we have no competing interests., (© 2024 The Author(s).)

The social complexity hypothesis (SCH) for communication states that the range and frequency of social interactions drive the evolution of complex communication systems. Surprisingly, few studies have empirically tested the SHC for vocal communication systems. Filling this gap is important because a co-evolutionary runaway process between social and vocal complexity may have shaped the most intricate communication system, human language. We here propose the African elephant Loxodonta spec . as an excellent study system to investigate the relationships between social and vocal complexity. We review how the distinct differences in social complexity between the two species of African elephants, the forest elephant L. cyclotis and the savanna elephant L. africana , relate to repertoire size and structure, as well as complex communication skills in the two species, such as call combination or intentional formant modulation including the trunk. Our findings suggest that Loxodonta may contradict the SCH, as well as other factors put forth to explain patterns of vocal complexity across species. We propose that life history traits, a factor that has gained little attention as a driver of vocal complexity, and the extensive parental care associated with a uniquely low and slow reproductive rate, may have led to the emergence of pronounced vocal complexity in the forest elephant despite their less complex social system compared to the savanna elephant. Conclusions must be drawn cautiously, however. A better understanding of vocal complexity in the genus Loxodonta will depend on continuing advancements in remote data collection technologies to overcome the challenges of observing forest elephants in their dense rainforest habitat, as well as the availability of directly comparable data and methods, quantifying both structural and contextual variability in the production of rumbles and other vocalizations in both species of African elephants.

Understanding the evolutionary consequences of wildlife exploitation is increasingly important as harvesting becomes more efficient. We examined the impacts of ivory poaching during the Mozambican Civil War (1977 to 1992) on the evolution of African savanna elephants ( Loxodonta africana ) in Gorongosa National Park. Poaching resulted in strong selection that favored tusklessness amid a rapid population decline. Survey data revealed tusk-inheritance patterns consistent with an X chromosome–linked dominant, male-lethal trait. Whole-genome scans implicated two candidate genes with known roles in mammalian tooth development ( AMELX and MEP1a ), including the formation of enamel, dentin, cementum, and the periodontium. One of these loci ( AMELX ) is associated with an X-linked dominant, male-lethal syndrome in humans that diminishes the growth of maxillary lateral incisors (homologous to elephant tusks). This study provides evidence for rapid, poaching-mediated selection for the loss of a prominent anatomical trait in a keystone species.