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Scorpionism, or envenomation caused by a scorpion sting, is a serious national public health hazard that particularly affects regions like the Middle East, North Africa, West Asia, South America, and Central America. Each year, an estimated 1.2 million incidents of scorpions’ sting take place around the world, with 3250 of them resulting in instant death. Scorpions use their poisonous stinging mechanism and pedipalps to catch prey animals and deter predators. Even though pedipalps and venom are found in all scorpions, the utilization is different across species, reflecting a trade-off structure. It is a common perception that more venomous scorpion species have lengthy, narrow chelae, such as several Buthidae species, but scorpion species such as Opistopthalmus glabrifrons that have a stronger chela, also have a proportionally lessdeveloped stinging mechanism, a shorter metasoma, or less effective toxin overall. Despite the overall prevalence of scorpionism, which is considerably greater owing to unidentified envenomation incidents, the morphology and ecological history of scorpions and their toxin are unexpectedly poorly understood. Thus, Forde and colleagues (2022) conducted a complex phylogenetic comparative analysis study to determine the association between the venom potency of the scorpions and their morphology and body size. The authors explicitly stated the research hypothesis in the article i.e., smaller species of scorpions with larger telsons and narrower chelae are more potent (indicated by lower LD50) than larger scorpion species. To test this hypothesis, a thorough literature study was done by the authors, and data was collected on the morphological characteristics and venom potency of different scorpion species. The authors did an initial web search for data related to the morphological characteristics and venom potency using keywords like "scorpion(s)", "scorpion LD50", "telson measure”, “total body size", "pedipalp measure", and related terms. The median lethal dose (LD50) was selected as a measure to assess venom potency while the width and the length of the scorpion telson and chela along with their total body size were used as a measure to assess scorpion morphological features. Next, for comparatively analyzing the data collected from a comprehensive literature study, the body size and LD50 values were transformed to log10, so that the model residuals could show a more normal distribution. Furthermore, the hypothesis was tested with the help of the Bayesian phylogenetic mixed models (BPMM), using the MCMCglmm package, which allows the study of the relationship among different explanatory variables and variant terms. The following figure 1 illustrates the working procedure utilized by the scientists to test their developed hypothesis. Hypothesis Literature Review Comparative Analysis Smaller species of scorpions with larger telsons and narrower chelae are more potent (indicated by lower LD50) than larger scorpion species To test the hypothesis, a thorough literature study was done, and data was collected on the morphological characteristics and venom potency of different scorpion species For comparatively analyzing the collected data, the body sized and LD50 were transformed to Log 10, and then the hypothesis was tested with the help of Bayesian phylogenetic mixed models (BPMM), using the MCMCglmm package. Figure 1: an illustration of the working procedure utilized by the scientists to test their developed hypothesis The dataset used by Forde and colleagues (2022) included 36 scorpion species and 62 LD50 measurements, all of which matched their inclusion criteria based on mammalian Mus musculus models. The dataset lethality values ranged from 0.16 mg/kg (shown by the deathstalker Leiurus quinquestriatus specie) to 1800 mg/kg (shown by the rock scorpion Hadogenes granulatus specie). The dataset body size values ranged from 40.5 mm to 200 mm, depicted by the bark scorpion Scorpion Centruroides noxious and H. granulatus, respectively. The median body size value of scorpions was found to be 70 mm. Moreover, the chela ratio in the dataset varied bet ween 0.7 and 6.2. The narrowest chelae were observed in the deathstalker Leiurus quinquestriatus while the strongest chelae were identified in the red scorpion Rhopalurus junceus and the large-clawed scorpion Scorpio maurus. Dataset analysis results (as shown in the following figures) revealed that a positive association exists between the body length and LD50 values whereas a negative association exists between the chelae ratio (morphological traits) and LD50 values. Figure 2: For 62 LD50 measures spanning over 36 scorpion species, the figure shows an association between log10 total length (mm) and log10 LD50 (mg/kg). The fitted line, corrected for the median chelae ratio value of 3.7, shows a strong positive connection between log10 total length and log10 LD50. The hollow yellow circles highlight the following species, which are indicated from right to left as Hadogenes granulatus; Androctonus crassicauda; Scorpio maurus; Scorpion Centruroides noxius; Hadogenes granulatus; Parabuthus transvaalicus; Androctonus crassicauda. Figure 3: For 62 LD50 measures spanning over 36 scorpion species, the figure shows an association between chelae and log10 LD50 (mg/kg). The fitted line, corrected for the median log10 total length value of 70 mm, shows a strong negative association between the chelae ratio and log10 LD50. The hollow red circles highlight the following species, which are indicated from right to left as Parabuthus transvaalicus, Scorpion Centruroides noxius, Hadogenes granulatus; Scorpio maurus. Thus, the study results significantly support the commonly accepted belief that smaller scorpion species with narrower chelae are more lethal as compared to bigger scorpions with stronger chelae. For instance, in the selected data set, the rock scorpion Hadogenes. granulatus, which is the largest species in the study, has the lowest toxic venom. Likewise, scorpions with large, robust chelae, including the Israeli gold scorpion Scorpio maurus, were linked to venoms that were relatively weak. The venoms of scorpions with thin chelae, like the South African thick-tail scorpion Parabuthus transvaalicus, were found to be more potent. To sum it all up, the study conducted by Forde and colleagues (2022) significantly contributes to the field of research by verifying the association between scorpion body size and venom toxicity. This study assists in recognizing the evolutionary and ecological determinants of venom potency of scorpions, which along with providing a basic understanding of scorpion species enables the individuals to handle the widespread scorpionism problem. Thus, this study empowers future researchers to address the issue of scorpionism based on venom potency and body size. However, the authors could have improved the study by evaluating the association of more scorpion morphological features like the metasoma with venom potency. This could have improved the results and provided a bigger picture as the metasoma thickness is also found to be associated with venom toxicity. Moreover, this could have also pointed to a link between the frequency with which a species uses venom and the assertion that organisms that depend on toxins for preying need more developed metasoma. Reference Forde, A., Jacobsen, A., Dugon, M. M., & Healy, K. 2022. Scorpion Species with Smaller Body Sizes and Narrower Chelae Have the Highest Venom Potency. Toxins. 14(3): 219.