TY - JOUR
T1 - Multiple parasitism reduces egg rejection in the host (Acrocephalus arundinaceus) of a mimetic avian brood parasite (Cuculus canorus)
AU - Manna, Thomas J.
AU - Moskát, Csaba
AU - Tong, Lainga
AU - Bán, Miklós
AU - Aidala, Zachary
AU - Low, Jason
AU - Hauber, Márk E.
N1 - Funding Information:
For discussions of our original data from 2013 on multiple parasitism and relaxed acceptance thresholds, we thank M. Stevens. We thank D. Lahti for additional advice. For funding, we are grateful to the Hungarian National Science Foundation (OTKA No. 83217 to Csaba Moskát), the National Research, Development and Innovation Office, Hungary (NKIF No. NN118194 to Csaba Moskát), the Human Frontier Science Program and the Harley Jones Van Cleave Professorship at the University of Illinois (to Márk E. Hauber). Lainga Tong was supported by a Presidential Research Fellowship from Hunter College. The Central Danube-Valley Inspectorate of Environment, Nature Conservation and Water Management, Hungary, kindly provided permissions for the research. All experiments were conducted in accordance with governmental and institutional research permits.
Publisher Copyright:
© 2019 American Psychological Association.
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2019
Y1 - 2019
N2 - A host that has been targeted by an avian brood parasite can recover most of its potential fitness loss by ejecting the foreign egg(s) from its nest. The propensity for some hosts to engage in egg rejection behavior has put selective pressure on their parasites to evolve mimetic eggshells resembling the host's own shell colors and maculation. In turn, hosts have counterevolved increasingly more sophisticated detection methods such as narrowing visual egg acceptance thresholds or using social cues to recognize parasitism. However, multiple cognitive mechanisms acting simultaneously could theoretically interfere with one another and ultimately decrease egg rejection accuracy, especially if these heuristics yield differing targets for rejection. By painting hosts own eggs, we studied a host species of the common cuckoo Cuculus canorus, the great reed warbler Acrocephalus arundinaceus, and tested its responses to the presence of "foreign" eggs of varying quantity, colors, and uniformity. Using reflectance spectra of egg background coloration and avian perceptual modeling, we then estimated the sensory thresholds triggering egg rejection by this host for each treatment. As previously reported, rejection rates were positively related to the perceptual distance between own and foreign eggs in the nests in all treatments. However, rejection thresholds were more permissive (error prone) both with greater proportions of foreign eggs per clutch and/or when the suite of foreign eggs was perceptually more variable within the nest. These results suggest that parasites, through multiple parasitism, can partially overcome the evolution of hosts' recognition of mimetic parasite eggs.
AB - A host that has been targeted by an avian brood parasite can recover most of its potential fitness loss by ejecting the foreign egg(s) from its nest. The propensity for some hosts to engage in egg rejection behavior has put selective pressure on their parasites to evolve mimetic eggshells resembling the host's own shell colors and maculation. In turn, hosts have counterevolved increasingly more sophisticated detection methods such as narrowing visual egg acceptance thresholds or using social cues to recognize parasitism. However, multiple cognitive mechanisms acting simultaneously could theoretically interfere with one another and ultimately decrease egg rejection accuracy, especially if these heuristics yield differing targets for rejection. By painting hosts own eggs, we studied a host species of the common cuckoo Cuculus canorus, the great reed warbler Acrocephalus arundinaceus, and tested its responses to the presence of "foreign" eggs of varying quantity, colors, and uniformity. Using reflectance spectra of egg background coloration and avian perceptual modeling, we then estimated the sensory thresholds triggering egg rejection by this host for each treatment. As previously reported, rejection rates were positively related to the perceptual distance between own and foreign eggs in the nests in all treatments. However, rejection thresholds were more permissive (error prone) both with greater proportions of foreign eggs per clutch and/or when the suite of foreign eggs was perceptually more variable within the nest. These results suggest that parasites, through multiple parasitism, can partially overcome the evolution of hosts' recognition of mimetic parasite eggs.
KW - Acceptance thresholds
KW - Coevolution
KW - Host-parasite interactions
KW - Sensory modeling
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U2 - 10.1037/com0000166
DO - 10.1037/com0000166
M3 - Article
C2 - 30667241
AN - SCOPUS:85060300828
SN - 0735-7036
VL - 133
SP - 351
EP - 358
JO - Journal of comparative psychology (Washington, D.C. : 1983)
JF - Journal of comparative psychology (Washington, D.C. : 1983)
IS - 3
ER -