TY - JOUR
T1 - Mimicry-dependent lateralization in the visual inspection of foreign eggs by American robins
AU - Scharf, Hannah M.
AU - Stenstrom, Katharine
AU - Dainson, Miri
AU - Benson, Thomas J
AU - Fernandez-Juricic, Esteban
AU - Hauber, Mark Erno
PY - 2019/7/26
Y1 - 2019/7/26
N2 - Brain lateralization, or the specialization of function in the left versus right brain hemispheres, has been found in a variety of lineages in contexts ranging from foraging to social and sexual behaviours, including the recognition of conspecific social partners. Here we studied whether the recognition and rejection of avian brood parasitic eggs, another context for species recognition, may also involve lateralized visual processing. We focused on American robins (Turdus migratorius), an egg-rejecter host to occasional brood parasitism by brown-headed cowbirds (Molothrus ater) and tested if robins preferentially used one visual hemifield over the other to inspect mimetic versus non-mimetic model eggs. At the population level, robins showed a significantly lateralized absolute eyedness index (EI) when viewing mimetic model eggs, but individuals varied in left versus right visual hemifield preference. By contrast, absolute EI was significantly lower when viewing non-mimetic eggs. We also found that robins with more lateralized eye usage rejected model eggs at higher rates. We suggest that the inspection and recognition of foreign eggs represent a specialized and lateralized context of species recognition in this and perhaps in other egg-rejecter hosts of brood parasites.
AB - Brain lateralization, or the specialization of function in the left versus right brain hemispheres, has been found in a variety of lineages in contexts ranging from foraging to social and sexual behaviours, including the recognition of conspecific social partners. Here we studied whether the recognition and rejection of avian brood parasitic eggs, another context for species recognition, may also involve lateralized visual processing. We focused on American robins (Turdus migratorius), an egg-rejecter host to occasional brood parasitism by brown-headed cowbirds (Molothrus ater) and tested if robins preferentially used one visual hemifield over the other to inspect mimetic versus non-mimetic model eggs. At the population level, robins showed a significantly lateralized absolute eyedness index (EI) when viewing mimetic model eggs, but individuals varied in left versus right visual hemifield preference. By contrast, absolute EI was significantly lower when viewing non-mimetic eggs. We also found that robins with more lateralized eye usage rejected model eggs at higher rates. We suggest that the inspection and recognition of foreign eggs represent a specialized and lateralized context of species recognition in this and perhaps in other egg-rejecter hosts of brood parasites.
KW - Avian brood parasitism
KW - Egg rejection
KW - Hemisphere
KW - Mimicry
UR - http://www.scopus.com/inward/record.url?scp=85070299452&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85070299452&partnerID=8YFLogxK
U2 - 10.1098/rsbl.2019.0351
DO - 10.1098/rsbl.2019.0351
M3 - Article
C2 - 31337293
SN - 1744-9561
VL - 15
JO - Biology Letters
JF - Biology Letters
IS - 7
M1 - 20190351
ER -