We examined ontogenetic differences in the expression of conditioned visual aversions. Sprague-Dawley-derived rats, 16 or 21 days of age, were conditioned with either an element (brightness) or compound (brightness/odor) CS+ and tested for their aversion to the common element (brightness). Aversions to the brightness cue were assessed by either a traditional test of preference between the CS+ brightness and a contrasting brightness or by assessment of freezing in the presence of either brightness cue. The results indicated that strength of conditioning as well as the expression of overshadowing/potentiation was dependent on the age of the animal and on the technique used to assess conditioning.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/dev.10081 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Over lifetime, organisms can be repeatedly exposed to stress, shaping their phenotype. At certain, so-called sensitive phases, individuals might be more receptive to such stress, for example, nutritional stress. However, little is known about how plastic responses differ between individuals experiencing nutritional stress early versus later in life or repeatedly, particularly in species with distinct ontogenetic niches.
View Article and Find Full Text PDFOntogeny of energy use in harvester ant colonies, and the metabolic expense of colony growth.
Proc Biol Sci
January 2025
School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA.
In animals, metabolic rates during ontogeny often scale differently from the way they do in cross-species or population comparisons, with near-isometric scaling patterns more often observed during juvenile growth. In multiple social insect taxa, colony metabolic rate scales hypometrically across species or populations at the same developmental stage, but metabolic patterns during ontogeny have not been examined for any social insect species. We performed the first ontogenetic study of social metabolic scaling in harvester ant colonies () over 3.
View Article and Find Full Text PDFPalatal segment contributions to midfacial anterior-posterior growth.
J Anat
January 2025
Department of Anthropology, Stony Brook University, Stony Brook, New York, USA.
Anterior-posterior (A-P) elongation of the palate is a critical aspect of integrated midfacial morphogenesis. Reciprocal epithelial-mesenchymal interactions drive secondary palate elongation that is coupled to the periodic formation of signaling centers within the rugae growth zone (RGZ). However, the relationship between RGZ-driven morphogenetic processes, the differentiative dynamics of underlying palatal bone mesenchymal precursors, and the segmental organization of the upper jaw has remained enigmatic.
View Article and Find Full Text PDFHindlimb muscles of the Emperor Penguin Aptenodytes forsteri (Aves, Sphenisciformes) at different postnatal ontogenetic stages.
J Anat
January 2025
División Paleontología Vertebrados, Museo de La Plata, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Buenos Aires, Argentina.
The Emperor Penguin Aptenodytes forsteri is the largest living species of penguin, found exclusively in Antarctica, and is unique in breeding during the winter. Consequently, fewer anatomical studies have been conducted on this species over time compared to others. This study aims to provide an updated and comprehensive description of the hindlimb musculature of Aptenodytes forsteri.
View Article and Find Full Text PDFFood web architecture and trophic interactions between organisms can be studied using ratios of naturally occurring stable isotopes of carbon (C/C) and nitrogen (N/N). Most studies, however, focused on free-living organisms, but recently, there has been growing interest in understanding trophic interactions of parasites. The crustacean ectoparasite is a well-studied parasite of freshwater teleost fish, which has low host specificity and a cosmopolitan distribution.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!