Plant phytochemicals can act as natural "medicines" for animals against parasites [1Huffman M.A. Animal self-medication and ethno-medicine: exploration and exploitation of the medicinal properties of plants.Proc. Nutr. Soc. 2003; 62: 371-381Crossref PubMed Scopus (245) Google Scholar, 2Singer M.S. Mace K.C. Bernays E.A. Self-medication as adaptive plasticity: increased ingestion of plant toxins by parasitized caterpillars.PLoS ONE. 2009; 4: e4796Crossref PubMed Scopus (194) Google Scholar, 3de Roode J.C. Lefèvre T. Hunter M.D. Ecology. Self-medication in animals.Science. 2013; 340: 150-151Crossref PubMed Scopus (162) Google Scholar]. Some nectar metabolites, for example, reduce parasite infections in bees [4Manson J.S. Otterstatter M.C. Thomson J.D. Consumption of a nectar alkaloid reduces pathogen load in bumble bees.Oecologia. 2010; 162: 81-89Crossref PubMed Scopus (126) Google Scholar, 5Gherman B.I. Denner A. Bobiş O. Dezmirean D.S. Mărghitaş L.A. Schluens H. Moritz R.F. Erler S. 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Historical nectar assessment reveals the fall and rise of floral resources in Britain.Nature. 2016; 530: 85-88Crossref PubMed Scopus (222) Google Scholar]. We identified 4-(3-oxobut-1-enylidene)-3,5,5-trimethylcyclohex-2-en-1-one (callunene) from heather nectar as a potent inhibitor of C. bombi. Wild bumblebees (Bombus terrestris) foraging on heather ingest callunene at concentrations causing complete C. bombi inhibition. Feeding on callunene was prophylactic against infections. We show that C. bombi establishes infections by flagellar anchoring to the ileum epithelium. Short-term callunene exposure induced flagellum loss in C. bombi choanomastigotes, resulting in a loss of infectivity. We conclude that plant secondary metabolites can disrupt parasite flagellum attachment, revealing a mechanism behind their prophylactic effects. The decline of heathlands [18Blackstock T.H. Stevens J.P. Howe E.A. Stevens D.P. 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Springer Science+Business Media, 1993Crossref Google Scholar] reduces the availability of natural bee "medicine" and could exacerbate the contribution of diseases to pollinator declines.Video AbstracteyJraWQiOiI4ZjUxYWNhY2IzYjhiNjNlNzFlYmIzYWFmYTU5NmZmYyIsImFsZyI6IlJTMjU2In0.eyJzdWIiOiIyZDgwNDk2NDk4NGFlYmRkMzVhMWM1MmRlNzBkODg1YSIsImtpZCI6IjhmNTFhY2FjYjNiOGI2M2U3MWViYjNhYWZhNTk2ZmZjIiwiZXhwIjoxNjc4MTk3MjYzfQ.Lcl4UKihoA0dcGxxI20wsJbeB6aLzEEGl5lFr-SLsXi1oRnWihfUvdsgF2HbctZNA-fmjXJvokUfTEXzvhKtPhTtgjfzFtettoGm_ZlezB_bOZ2tSWN8iI_Mi0Yxgl3uLnhBQZnbiskQblLVl5rD8V_HGS6za8OG7usqIN5jHp1pKed_4GsN144gQwc5Tz66IoGgRWA6Ns522YnFPkLRE20Qh5-QauSOSV0BsBa3W6oHSakTFxoSgOvJNYj9IBO6B-iDQKZJMhSFfZDX6Seu9jSfXn5s1i4LVlW79qqSlY_Qq0LKkrYYx0R-GmR66psuLsfB191c87-DmnOKyUDXxg(mp4, (401.21 MB) Download video
A quad tree, stored without links and with a location for every possible node, is proposed as a structure for holding an image under construction. In this form, picture coherence is not exploited to reduce storage requirements, but to improve the speed of interrogation and modification. Basic operations on this structure are outlined, and an efficient addressing scheme presented.
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