A1 Refereed original research article in a scientific journal

Maternal food supplementation and perceived predation risk modify egg composition and eggshell traits but not offspring condition




AuthorsMorosinotto C, Thomson RL, Korpimaki E, Mateo R, Ruuskanen S

PublisherCOMPANY BIOLOGISTS LTD

Publishing placeCAMBRIDGE

Publication year2019

JournalJournal of Experimental Biology

Journal name in sourceJOURNAL OF EXPERIMENTAL BIOLOGY

Journal acronymJ EXP BIOL

Article numberUNSP jeb201954

Volume222

Issue19

Number of pages9

ISSN0022-0949

eISSN1477-9145

DOIhttps://doi.org/10.1242/jeb.201954


Abstract
Mothers may vary resource allocation to eggs and embryos, which may affect offspring fitness and prepare them for future environmental conditions. The effects of food availability and predation risk on reproduction have been extensively studied, yet their simultaneous impacts on reproductive investment and offspring early life conditions are still unclear. We experimentally manipulated these key environmental elements using a 2x2 full factorial design in wild, free-living pied flycatchers (Ficedula hypoleuca), and measured egg composition, eggshell traits and offspring condition. Eggs laid in food-supplemented nests had larger yolks and thicker shells independently of predation risk, while eggs laid in nests exposed to predator cues had lower levels of immunoglobulins, independent of food supplementation. In nests without predator cues, shell biliverdin content was higher in eggs laid in food-supplemented nests. Incubation was 1 day shorter in food-supplemented nests and shorter incubation periods were associated with higher hatching success, but there were no direct effects of maternal treatment on hatching success. To investigate the impact of maternal treatment (via egg composition) on the offspring, we performed full brood cross-fostering after hatching to unmanipulated nests. Maternal treatment did not significantly affect body mass and immunoglobulin levels of offspring. Our results suggest that although prenatal maternal cues affected egg composition, these egg-mediated effects may not have detectable consequences for offspring growth or immune capacity. Unpredictable environmental stressors may thus affect parental investment in the eggs, but parental care may level off costs and benefits of differential maternal egg allocation.



Last updated on 2024-26-11 at 12:36