Papers by Harry Ward-Smith
Vertebrate zoology, Apr 26, 2024
The Herpetological Bulletin, Apr 1, 2021
Toxins, Mar 22, 2020
Animals use venoms for multiple purposes, most prominently for prey acquisition and self-defense.... more Animals use venoms for multiple purposes, most prominently for prey acquisition and self-defense. In snakes, venom composition often evolves as a result of selection for optimization for local diet. However, whether selection for a defensive function has also played a role in driving the evolution of venom composition has remained largely unstudied. Here, we use an online survey of snakebite victims to test a key prediction of a defensive function, that envenoming should result in the rapid onset of severe pain. From the analysis of 584 snakebite reports, involving 192 species of venomous snake, we find that the vast majority of bites do not result in severe early pain. Phylogenetic comparative analysis shows that where early pain after a bite evolves, it is often lost rapidly. Our results, therefore, do not support the hypothesis that natural selection for antipredator defense played an important role in the origin of venom or front-fanged delivery systems in general, although there may be intriguing exceptions to this rule.
Toxins, 2020
Animals use venoms for multiple purposes, most prominently for prey acquisition and self-defense.... more Animals use venoms for multiple purposes, most prominently for prey acquisition and self-defense. In snakes, venom composition often evolves as a result of selection for optimization for local diet. However, whether selection for a defensive function has also played a role in driving the evolution of venom composition has remained largely unstudied. Here, we use an online survey of snakebite victims to test a key prediction of a defensive function, that envenoming should result in the rapid onset of severe pain. From the analysis of 584 snakebite reports, involving 192 species of venomous snake, we find that the vast majority of bites do not result in severe early pain. Phylogenetic comparative analysis shows that where early pain after a bite evolves, it is often lost rapidly. Our results, therefore, do not support the hypothesis that natural selection for antipredator defense played an important role in the origin of venom or front-fanged delivery systems in general, although ther...
The Herpetological Bulletin, 2021
T banded kukri snake (Oligodon fasciolatus) is a primarily nocturnal, terrestrial species that re... more T banded kukri snake (Oligodon fasciolatus) is a primarily nocturnal, terrestrial species that reaches a maximum length of 920 mm in males and 863 mm in females. It is typically grey in colour but may vary from red to brown. Encountered throughout mainland south-east Asia, this species is a habitat generalist being found in agricultural landscapes and tropical forests up to 900 m asl (Cox et al., 2012). Oligodon species possess enlarged posterior maxillary teeth that evolved to slice through a specialised diet of frogs and reptile eggs. This dentition results in bites that are characterised by deep, clean, bloody wounds. Herein we present only the second report of combat between males in the genus Oligodon; with a historic report in Oligodon taeniatus recently being uncovered (Gray, 2021). During a herpetofaunal survey on the 26th December 2018 in Sakaerat Biosphere Reserve, Nakhon Ratchasima, Thailand (14.5025 ̊ N, 101.9248 ̊ E, Datum 47P, 511 m asl), we observed two adult male O. ...
Animals use venoms for multiple purposes, most prominently for prey acquisition and self-defense.... more Animals use venoms for multiple purposes, most prominently for prey acquisition and self-defense. In snakes, venom composition often evolves as a result of selection for optimization for local diet. However, whether selection for a defensive function has also played a role in driving the evolution of venom composition has remained largely unstudied. Here, we use an online survey of snakebite victims to test a key prediction of a defensive function, that envenoming should result in the rapid onset of severe pain. From the analysis of 584 snakebite reports, involving 192 species of venomous snake, we find that the vast majority of bites do not result in severe early pain. Phylogenetic comparative analysis shows that where early pain after a bite evolves, it is often lost rapidly. Our results, therefore, do not support the hypothesis that natural selection for antipredator defense played an important role in the origin of venom or front-fanged delivery systems in general, although there may be intriguing exceptions to this rule.
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Papers by Harry Ward-Smith