Once upon a time, insects had 24 legs

Once upon a time, insects had 24 legs

Once upon a time, insects had 24 legs. This ancient oddball fills a major gap in the fossil record. Insects are famous for their six-legged body plan, but that wasn't always the rule. A 324-million-year-old fossil dug up from a shale bed in West Texas had a markedly different setup, sporting a whopping 18 extra legs along its belly — a body plan unlike that of any living insect.