Spider venom peptides Ht1a and Gg1a are toxic to honeybee parasite Varroa destructor by topical application

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  Spider venom peptides Ht1a and Gg1a are toxic to honeybee parasite Varroa destructor by topical application Abstract Global food supply strongly depends on honeybee pollination services, which are threatened by insecticides and pests such as parasitic Varroa destructor mites. Chemical varroacides/acaricides are hampered by resistance development, necessitating the development of sustainable and environmentally friendly alternatives, with arthropod venom peptides being considered promising sources of acaricidal toxins. With only a few acaricidal venom peptides being reported, we performed a systematic topical screening of 50 arthropod venoms against V. destructor , with 78% of the venoms causing 100% mortality after 24 h. Deconvolution of the venoms from the Tasmanian cave spider Hickmania troglodytes and the Giant Japanese funnel-web spider Gigathele gigas led to identification of the varroacidal peptides Ht1a and Gg1a. Topical application of Ht1a and Gg1a reduced varroa mite ...

Unsupervised learning reveals rapid gait adaptation after leg loss and regrowth in spiders

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Unsupervised learning reveals rapid gait adaptation after leg loss and regrowth in spiders

Many invertebrates voluntarily lose (autotomize) limbs during antagonistic encounters, and some regenerate functional replacements. Because limb loss can have severe consequences on individual fitness, it is likely subject to significant selective pressures, making this an excellent phenomenon with which to investigate biomechanical robustness. Spiders frequently autotomize one or more legs. We investigated the time course of locomotor recovery after leg loss and regeneration in juvenile tarantulas (Arachnida: Araneae) naive to autotomy. We recorded high-speed video of spiders running with all legs intact, then immediately after, and again 1 day after they had autotomized two legs. The legs were allowed to regenerate, and the same sequence of experiments was repeated. Video tracking analysis revealed that the spiders resumed their pre-autotomy speed and stride frequency after leg regeneration and in ≤1 day after both autotomies; path tortuosity was unaffected by these treatments. Autotomized spiders widened the spread of their remaining legs for stability and to compensate for missing functional space. To analyze how their gaits changed in response to leg loss, we applied unsupervised machine learning for the first time to measured kinematic data in combination with gait space metrics. Spiders were found to robustly adopt new gait patterns immediately after losing legs, with no evidence of learning. This novel clustering approach both demonstrated concordance with hypothesized gaits and revealed transitions between and variations within these patterns. More generally, clustering in gait space enables the identification of patterns of leg motions in large datasets that correspond to either known gaits or undiscovered behaviors.




Suzanne Amador Kane, Brooke L. Quinn, Xuanyi Kris Wu, Sarah Y. Xi, Michael F. Ochs, S. Tonia Hsieh; Unsupervised learning reveals rapid gait adaptation after leg loss and regrowth in spiders. J Exp Biol 15 June 2025; 228 (12): jeb250243. doi: https://doi.org/10.1242/jeb.250243