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Why are dormice placed differently in some rodent classification systems?

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black-tailed prairie dog — rodent Black-tailed prairie dog (*Cynomys ludovicianus*).

Dormice (family Myoxidae) are placed differently in various rodent classification systems because their evolutionary relationships to other rodents remain unclear.1

Historically, specialists have disagreed on how to arrange rodent families into suborders, leading to different taxonomic hypotheses. Dormice have been allied with two distinct major groups:2
* Sciuromorpha: The squirrel-like rodents.12
* Myomorpha: The mouselike rodents.12

Because the closest living relatives of dormice are unknown, their placement within these suborders is often disputed. While some modern classifications include Myoxidae within the suborder Myomorpha, this remains a subject of ongoing scientific testing and analysis. Any such arrangement is considered a hypothesis that is continually re-evaluated through the discovery of new fossils and the application of new analytical techniques, such as DNA sequencing and comparative anatomy.12