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Investigating intentionality in elephant gestural communication
No full textA crucial feature of language is the ability to communicate cognitive goals to a specific audience, i.e. goal-directed intentionality. Core criteria for this ability include (i) audience directedness: signalling in the presence of an attentive audience, (ii) persistence: continuing signalling until goals are met, and (iii) elaboration: using new signals following communicative failure. While intentional use has been demonstrated in individual gestures in some non-primates, primates—in particular apes—show this ability across many gestures. But is goal-directed intentionality across many gestures restricted to primates? We explored whether savannah elephants use many gestures with goal-directed intentionality. We presented semi-captive elephants with desired and non-desired items, recording their communicative attempts when an experimenter met, partially met or failed to meet their goal of getting the desired item. Elephants used 38 gesture types almost exclusively when a visually attentive experimenter was present, demonstrating audience directedness. They persisted in gesturing more when their goal was partially as compared with fully met but showed no difference in persistence when the goal was met or not met. Elephants elaborated their gesturing when their goal was not met. We find goal-directed intentionality across many elephant gestures and reveal that elephants, like apes, assess the communicative effectiveness of their gesturing
From water to land:a review on the applications of environmental DNA and invertebrate-derived DNA for monitoring terrestrial and semi-aquatic mammals
No full text1. Terrestrial and semi-aquatic mammals are facing increasing threats globally, highlighting the need for reliable data on species' occurrence, distribution, and abundance for effective conservation efforts. However, obtaining reliable and robust information over broad spatial and temporal scales remains a significant challenge.2. Environmental DNA (eDNA) and invertebrate-derived DNA (iDNA) applications have emerged as powerful surveying methods, with the potential to revolutionise ecological monitoring by improving species detections and providing better insights into mammalian distribution and diversity. While eDNA relies on genetic material shed by species into their surroundings, iDNA leverages DNA from invertebrates that interact with mammals. Both approaches offer a cost-effective means to obtain species records and community diversity metrics.3. This review explores global applications of e/iDNA for surveying terrestrial and semi-aquatic mammals. By providing a comprehensive overview of the applications, sampling design, challenges, and prospects, this review serves as a guide to researchers and conservationists seeking to use eDNA for mammalian conservation efforts.4. By evaluating the current state of e/iDNA applications, this review identifies the challenges and milestones that need to be addressed for these methods to become a practical method for monitoring mammals on a global scale. It highlights the need for further research to enhance the sensitivity and reliability of e/iDNA detections, standardisation of methodologies, and validation through comparison with traditional monitoring methods. This review sheds light on the potential of e/iDNA as valuable tools for aiding mammal conservation and inspiring future research and advancements in this field
Eleven new transiting brown dwarfs and very low mass stars from TESS
No full textWe present the discovery of 11 new transiting brown dwarfs (BDs) and low-mass M dwarfs from NASA’s Transiting Exoplanet Survey Satellite (TESS) mission: TOI-2844, TOI-3122, TOI-3577, TOI-3755, TOI-4462, TOI-4635, TOI-4737, TOI-4759, TOI-5240, TOI-5467, and TOI-5882. They consist of five BD companions and six very-low-mass stellar companions ranging in mass from 25 MJ to 128 MJ. We used a combination of photometric time-series, spectroscopic, and high-resolution imaging follow-up as a part of the TESS Follow-up Observing Program (or TFOP) to characterize each system. With over 50 transiting BDs confirmed, we now have a large enough sample to directly test different formation and evolutionary scenarios. We provide a renewed perspective on the transiting “brown dwarf desert” and its role in differentiating between planetary and stellar formation mechanisms. Our analysis of the eccentricity distribution for the transiting BD sample does not support previous claims of a transition between planetary and stellar formation at ∼42 MJ. We also contribute a first look into the metallicity distribution of transiting companions in the range 7–150 MJ, showing that this does not support a ∼42 MJ transition too. Finally, we also detect a significant lithium absorption feature in one of the BD hosts (TOI-5882). However, we determine that the host star is likely old based on rotation, kinematic, and photometric measurements. We therefore claim that TOI-5882 may be a candidate for planetary engulfment
Developing, evaluating, and interpreting personality state measures:a framework based on the revised latent state-trait theory
No full textStates are increasingly important in personality theory and research. Yet, the assessment of personality states usually relies on ad hoc measures whose development and evaluation are largely separated from theoretical considerations. To enable theory-guided development and evaluation of personality state measures, we introduce a framework based on the revised latent state-trait (LST-R) theory. The theory defines latent states as the expectation of an observed measure given a person in a specific situation, which can be decomposed into latent traits and latent situation-specific state residuals. Consequently, items and scales can be evaluated for their reliability due to latent traits (consistency) and situation-specific influences (specificity). We propose that specificity, in particular, is an appealing property for instruments designed to assess personality states. We illustrate this framework with experience sampling data on personality states. Our framework has implications for both the conceptualisation and the assessment of personality states. On the theoretical side, we provide a formal definition of personality states, which enables integration between trait-, process-, and development-focused theories. On the practical side, we show how using LST-R models allows researchers to develop and evaluate state measures on their own terms rather than applying criteria for trait measures to assess the qualities of state measures.</p
The effects of seawater temperature-induced coral bleaching on the aragonite structure and material properties of massive <i>Porites lutea</i> coral skeletons
No full textThe coral skeletons that contribute to tropical reef structures are biominerals, composed of inorganic aragonite and organic biomolecules. The biomolecules influence the aragonite structure and material properties of the skeleton. We collected massive Porites lutea skeletons from Phuket, Thailand, in 1991, approximately one month into a temperature-induced bleaching event. Some specimens had expelled their Symbiodiniaceae in response to the increased water temperatures (bleached), while other corals appeared unaffected (unbleached). We investigate the effect of Symbiodiniaceae loss on the amino acid composition, aragonite structure, and Vickers hardness of the coral skeletons. We observe no significant difference in the amino acid content or composition of the outermost 1 mm of skeleton (representing 0.5 to 2 months growth) between bleached and unbleached specimens. The full width half maximum of the Raman spectrum ʋ1 band, an indicator of disorder around the CO3 group in the aragonite lattice, varies significantly between some corals in the outermost 200 µm of skeleton, but these differences are not attributable to the bleaching status of the coral colonies. Similarly, Vickers hardness varies significantly between some colonies, but this is not related to coral bleaching. This is a positive finding, suggesting that bleaching, from which corals recover, does not adversely affect the coral skeletal structure
