3840
Phylogenetic investigations revealed that these Arseno - phonus strains do not cluster within an aphid - specific clade but rather exhibit distinct evolutionary origins showing that they undergo repeated horizontal transfers ( HT ) between distantly related host species .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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