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Title: Beetle horns evolved from wing serial homologs
Understanding how novel complex traits originate is a foundational challenge in evolutionary biology. We investigated the origin of prothoracic horns in scarabaeine beetles, one of the most pronounced examples of secondary sexual traits in the animal kingdom. We show that prothoracic horns derive from bilateral source tissues; that diverse wing genes are functionally required for instructing this process; and that, in the absence of Hox input, prothoracic horn primordia transform to contribute to ectopic wings. Once induced, however, the transcriptional profile of prothoracic horns diverges markedly from that of wings and other wing serial homologs. Our results substantiate the serial homology between prothoracic horns and insects wings and suggest that other insect innovations may derive similarly from wing serial homologs and the concomitant establishment of structure-specific transcriptional landscapes.  more » « less
Award ID(s):
1901680
NSF-PAR ID:
10137359
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Science
Volume:
366
Issue:
6468
ISSN:
0036-8075
Page Range / eLocation ID:
1004 to 1007
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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