| Moonstruck primates: owl monkeys (Aotus) need moonlight for nocturnal activity in their natural environment. | |
| | |
MedLine Citation:
|
PMID: 20838447 Owner: NLM Status: In-Process |
Abstract/OtherAbstract:
|
Primates show activity patterns ranging from nocturnality to diurnality, with a few species showing activity both during day and night. Among anthropoids (monkeys, apes and humans), nocturnality is only present in the Central and South American owl monkey genus Aotus. Unlike other tropical Aotus species, the Azara's owl monkeys (A. azarai) of the subtropics have switched their activity pattern from strict nocturnality to one that also includes regular diurnal activity. Harsher climate, food availability, and the lack of predators or diurnal competitors, have all been proposed as factors favoring evolutionary switches in primate activity patterns. However, the observational nature of most field studies has limited an understanding of the mechanisms responsible for this switch in activity patterns. The goal of our study was to evaluate the hypothesis that masking, namely the stimulatory and/or inhibitory/disinhibitory effects of environmental factors on synchronized circadian locomotor activity, is a key determinant of the unusual activity pattern of Azara's owl monkeys. We use continuous long-term (6-18 months) 5-min-binned activity records obtained with actimeter collars fitted to wild owl monkeys (n = 10 individuals) to show that this different pattern results from strong masking of activity by the inhibiting and enhancing effects of ambient luminance and temperature. Conclusive evidence for the direct masking effect of light is provided by data showing that locomotor activity was almost completely inhibited when moonlight was shadowed during three lunar eclipses. Temperature also negatively masked locomotor activity, and this masking was manifested even under optimal light conditions. Our results highlight the importance of the masking of circadian rhythmicity as a determinant of nocturnality in wild owl monkeys and suggest that the stimulatory effects of dim light in nocturnal primates may have been selected as an adaptive response to moonlight. Furthermore, our data indicate that changes in sensitivity to specific environmental stimuli may have been an essential key for evolutionary switches between diurnal and nocturnal habits in primates. |
| | |
Authors:
|
Eduardo Fernández-Duque; Horacio de la Iglesia; Hans G Erkert |
Related Documents
:
|
6772277 - Temporal response characteristics of cells in monkey striate cortex measured with metac... 20695697 - Competing for consciousness: prolonged mask exposure reduces object substitution masking. 2712797 - Detectability of emergency lights for underwater escape. 4000867 - Interhemispheric visual masking. 21808327 - Self-induced transparency and the anderson localization of light. 2594377 - The effect of spatial frequency on binocular contrast inhibition. |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't Date: 2010-09-03 |
Journal Detail:
|
Title: PloS one Volume: 5 ISSN: 1932-6203 ISO Abbreviation: PLoS ONE Publication Date: 2010 |
Date Detail:
|
Created Date: 2010-09-14 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 101285081 Medline TA: PLoS One Country: United States |
Other Details:
|
Languages: eng Pagination: e12572 Citation Subset: IM |
Affiliation:
|
Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America. eduardof@sas.upenn.edu |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Methodological underestimation of oceanic nitrogen fixation rates.
Next Document: A PPAR? promoter variant impairs ERR-dependent transactivation and decreases mortality after acute c...