98%
921
2 minutes
20
Investment in one life-history stage can have delayed effects on subsequent life-history stages within a single reproductive bout. We experimentally heated tree swallow (Tachycineta bicolor) nests during incubation to test for effects on parental and nestling conditions. Females incubating in heated boxes maintained higher body condition and fed nestlings at higher rates. We cross-fostered nestlings and found that young nestlings (4-7 days old) incubated in heated nests had higher body condition and body mass, regardless of treatment status of their rearing parent. However, older nestlings which were fed by heated females maintained higher condition and body mass regardless of treatment status of their incubating parent. These results indicate that investment in one life-history stage can have multiple pathways of carry-over effects on future life-history stages.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2610083 | PMC |
http://dx.doi.org/10.1098/rsbl.2008.0266 | DOI Listing |
J Exp Zool A Ecol Integr Physiol
October 2025
Department of Biology, Indiana University. Bloomington, IN, USA.
The ovary is key to linking environmental factors with the timing and quality of offspring development. Focused on free-living female tree swallows (Tachycineta bicolor), we measured temporal variation in ovarian expression of genes involved in the regulation of telomere length. Using qPCR, we quantified mRNA abundance of shelterin proteins (TERF1, TERF2, TERF2IP, TPP1, POT1), telomerase (TERT), antioxidants (SOD1, PRDX-1, GPX), and glucocorticoid receptors (MR, GR).
View Article and Find Full Text PDFEnviron Monit Assess
May 2025
U.S. Geological Survey, Wyoming-Montana Water Science Center, Helena, MT, USA.
Selenium (Se) levels in water have been increasing in Lake Koocanusa and the Kootenai River below Libby Dam in Montana due to coal mining in the drainage basin of the Elk River, British Columbia. Aquatic monitoring of Se is ongoing to assess potential effects; however, exposure to terrestrial, aquatic-dependent wildlife has not been investigated. Tree swallows are a targeted receptor for evaluation of potential Se-related effects as this species is a mid-level consumer with aquatic-terrestrial food web linkages, is sensitive to Se, and reliably uses nest boxes.
View Article and Find Full Text PDFHorm Behav
March 2025
Indiana University, Department of Biology, United States of America.
Territorial competition can stimulate secretion of testosterone (T), which is thought to act on neural circuits of aggression to promote further aggression. Here, we test the hypothesis that competition modulates sex steroid sensitivity and conversion in the brain, focused on the female tree swallow (Tachycineta bicolor). In this bird species, exogenous T enhances female aggression, but social competition for limited nesting territories does not stimulate systemic T elevation.
View Article and Find Full Text PDFHorm Behav
February 2025
Indiana University Bloomington, Department of Biology, 1001 E 3rd St, Bloomington, IN 47405, United States of America. Electronic address:
Aggressive behavior is ubiquitous across many contexts, including defense of territories, mates, and offspring. For decades, researchers have detailed the effect of aggressive behavior on physiology, but our understanding of these mechanisms in females lags behind that of males, despite the fact that female aggression is widespread, particularly in the context of maternal defense of eggs or offspring (i.e.
View Article and Find Full Text PDFJ Evol Biol
February 2025
Département de Biologie, Université de Sherbrooke, Sherbrooke, Canada.
Several studies have emphasized that phenotypic plasticity should be a key mechanism to cope with current rapid environmental changes by allowing individuals to quickly express new adaptive phenotypes. Yet, few studies have investigated the evolutionary potential of plasticity for multiple traits simultaneously and using several different environmental variables. Here, we assess the extent of variation in, and the selection acting on phenotypic plasticity of key ecological traits, laying date, and clutch size, using five environmental variables, in a Tree swallow (Tachycineta bicolor) population monitored since 2004.
View Article and Find Full Text PDF