Herpetological misinformation and sensationalism: media framing on biological and ecological aspects of the golden lancehead (Bothrops insularis)

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  Herpetological misinformation and sensationalism: media framing on biological and ecological aspects of the golden lancehead (Bothrops insularis) Abstract The internet is currently one of the most important means of communication, which may include the circulation of misinformation. Snakes have always been a target of the sensationalist media, being pictured as scary and aggressive animals to be killed indiscriminately by humans. Such fear based on misinformation may compromise species conservation. Here, we address the spread of misinformation about Bothrops insularis and Queimada Grande Island in digital media, highlighting the negative impact on public perception and species conservation. The analysis of 230 online sources revealed that approximately 94% of them contained false information, many using sensationalist language, especially regarding the toxicity of the venom and the population density of the snake, as well as bringing contents that did not align with scientific d...

How to give a spider a heart attack: Evaluating cardiac stress reactions of Trichonephila and Argiope spiders

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How to give a spider a heart attack: Evaluating cardiac stress reactions of Trichonephila and Argiope spiders

Abstract

All animal species, from arthropods to vertebrates, must deal with occasional stressors in their lives, though most research on this has been focused on vertebrates. Meanwhile, our understanding of stress reactions in arthropod species like spiders is nascent. In the United States, a non-native orb-weaving spider, Trichonephila clavata (‘jorō’ spider), is spreading as is its already-established cousin in the United States, T. clavipes (golden silk spider). Prior study has revealed how these two species have a unique behavioural reaction to physical stressors, whereby they remain in a thanatosis state for a prolonged period compared with other species. Here, we investigate the physiological stress reactions of these Trichonephila spiders by evaluating how each species' dorsal vessel contractions (heart rates) become elevated after being subjected to a non-lethal stressor. For comparison, we also evaluate two similarly-sized orb weavers, Argiope aurantia (garden spider) and A. trifasciata (banded garden spider). We record baseline heart rates of inactive, resting, spiders in our lab, then restrain them under an electronic, ‘optocardiographic’, sensor for 10 min, to record their ‘stressed’ heart rates. Argiope aurantia has a pronounced heart rate elevation, for reasons unknown. We observe that all spider heart rates increase during restraint, though each has a species-specific pattern of elevation over time under restraint. Notably, heart rates of both Trichonephila spiders are less variable under stress, since they tend not to struggle during restraint. Meanwhile, both Argiope spiders frequently struggle, leading to marked fluctuations in cardiac output. The stress reactions of Trichonephila spiders could be characterized as ‘even-tempered’, which may factor into their ability to live in habitats with frequent disturbances.

Davis, A. K., & Vu, C. How to give a spider a heart attack: Evaluating cardiac stress reactions of Trichonephila and Argiope spiders. Physiological Entomology. https://doi.org/10.1111/phen.12463