Biological Rhythmicity in Subterranean Animals: A Function Risking Extinction?
- Permanent Link:
- Biological Rhythmicity in Subterranean Animals: A Function Risking Extinction?
- Series Title:
- Mechanisms of Circadian Systems in Animals and Their Clinical Relevance
- Barreto, Luiz Menna
- Publication Date:
- Subjects / Keywords:
- Locomotor Activity ( local )
Circadian Timing System ( local )
Cave Fish ( local )
Cave Form ( local )
Armored Catfish ( local )
- serial ( sobekcm )
- In this chapter, we discuss evidence of regression of circadian locomotor activity in exclusively subterranean species (troglobites), having fishes as models, by comparing such findings with observations on related epigean (surface) species, that may also form self-sustained subterranean (troglophilic) populations. These results favor the hypothesis of regression of a function which may have lost its adaptive value for species permanently isolated in hypogean habitats for many generationsâ€”regression similar to the reduction of eyes and dark pigmentation, typical of troglobites in general. Recent data on feeding behavior of blind catfish compared to epigean congeners suggest a process of partial regression, affecting locomotion but not feeding, due perhaps to the persistence of regular food availability in the otherwise continuously dark cave environment. Among non-troglobitic subterranean animals, trogloxenes present regular, cyclical movements between hypogean and epigean habitats, whereas troglophiles may move between these habitats, promoting genetic connectivity between surface and subterranean populations, but without following well-defined rhythmic patterns.
- Source Institution:
- University of South Florida Library
- Holding Location:
- University of South Florida
- Rights Management:
- This object is protected by copyright, and is made available here for research and educational purposes. Permission to reuse, publish, or reproduce the object beyond the bounds of Fair Use or other exemptions to copyright law must be obtained from the copyright holder.
No images or PDF downloads are available for this resource.
Cras ut cursus ante, a fringilla nunc. Mauris lorem nunc, cursus sit amet enim ac, vehicula vestibulum mi. Mauris viverra nisl vel enim faucibus porta. Praesent sit amet ornare diam, non finibus nulla.
Cras efficitur magna et sapien varius, luctus ullamcorper dolor convallis. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Fusce sit amet justo ut erat laoreet congue sed a ante.
Phasellus ornare in augue eu imperdiet. Donec malesuada sapien ante, at vehicula orci tempor molestie. Proin vitae urna elit. Pellentesque vitae nisi et diam euismod malesuada aliquet non erat.
Nunc fringilla dolor ut dictum placerat. Proin ac neque rutrum, consectetur ligula id, laoreet ligula. Nulla lorem massa, consectetur vitae consequat in, lobortis at dolor. Nunc sed leo odio.