Photoperiodic Time Measurement in the Male Deer Mouse by Underwood - Article Example

Photoperiodic time measurement relies on a daily (circadian) rhythm of sensitivity to light; during one-half of a circadian cycle, the organism is insensitive but during the remainder of the cycle, they become sensitive to the inductive effects (Underwood et al., 1985). The circadian system is involved in photoperiodic time measurement up to date in several species of mammals. The circadian rhythm of locomotors activity is applied as an assay for the phase of an animal’s circadian clock typically because of its ease of measurement.

This study was conducted to assess the nature of photoperiodic time measurement in the prairie deer mouse (P. maniculatus) by examining both gonadal development and locomotor activity patterns in individuals exposed to various 24-h and non-24-h LD cycles (Underwood et al., 1985). There is important background information that led to the work discussed in this article. That is, the annual change in day length provides a precise, noise-free cue that many temperate-zone animals use to time such significant events as fattening, migration, molting, and reproduction.

Animals can anticipate, and prepare for conditions that are most conducive to their survival as well as the survival of their offspring. It is, therefore, need to know these different reactions for better survival that led to the writing of this article. The issue described in this article is important since it is not only applicable to prairie deer mice but can also be applicable to human beings. Furthermore, with agriculture and livestock production becoming a backbone of economic development, this issue will help farmers significantly to know how to treat handle livestock during different times of the day and seasons.

The authors found that the nightly melatonin “pulse” is the cue by which these animals discriminate between photo periodically inductive and noninductive day length.