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Insects have three thoracic (trunk) segments. While researchers have found fossils with wings on all segments, modern insects have wings or related structures on only the second and third segments. Hox gene products inhibit wing formation on the first segment. The treehopper is an exception. Its first segment has an ornate helmet that is a modified fused pair of "wings." which provide camouflage in branches, reducing risk of predation. Explain how changes in gene regulation could have led to this evolution.
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