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Title: Night-time neuronal activation of Cluster N in a North American songbird
Night-migrating songbirds utilize the Earth’s magnetic field to help navigate to and from their breeding sites each year. A region of the avian forebrain called Cluster N has been shown to be activated during night migratory behavior and it has been implicated in processing geomagnetic information. Previous studies with night-migratory European songbirds have shown that neuronal activity at Cluster N is higher at night than during the day. Comparable work in North American migrants has only been performed in one species of swallows, so extension of examination for Cluster N in other migratory birds is needed. In addition, it is unclear if Cluster N activation is lateralized and the full extent of its boundaries in the forebrain have yet to be described. We used sensory-driven gene expression based on ZENK and the Swainson’s thrush, a night-migratory North American songbird, to fill these knowledge gaps. We found elevated levels of gene expression in night- vs. day-active thrushes and no evidence for lateralization in this region. We further examined the anatomical extent of neural activation in the forebrain using 3D reconstruction topology. Our findings demonstrate that Swainson’s thrushes possess an extensive bilateral night-activated Cluster N region in the forebrain similar to other European avian species, suggesting that Cluster N is highly conserved in nocturnal migrants.  more » « less
Award ID(s):
2143004
PAR ID:
10573334
Author(s) / Creator(s):
; ; ; ;
Editor(s):
Mpodozis, Jorge Marin
Publisher / Repository:
PLOS ONE
Date Published:
Journal Name:
PLOS ONE
Volume:
19
Issue:
3
ISSN:
1932-6203
Page Range / eLocation ID:
e0300479
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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