水槽中の魚の分布に対する諸種の光の影響の統計的解析-I
暗黒に慣らされた魚に対する諸種の光の影響
1955 年 21 巻 3 号 p. 159-163
詳細
1955 年 21 巻 3 号 p. 159-163
1. Lights of various intensities and colours were shed on the aqualium in which 10 young individuals of dark-adapted Girella punctata GRAY were kept.
2. The out-line and the size of the aqualia and the positions of lights are shown in Fig. 1. In order to make possible to avoid the beam, during the experiment each aqualium is illuminated only at a half.
3. Lights, 5 grade of intensities and 6 colours, are used.
4. Individuals of Girella punctata used for these experiments are scattered almost every part of the aqualium in the day time or at night showing more or less territorial behaviours and do not form conspicuous shoal.
5. Number of individuals observed in each part of the aqualium in each case 30min. after the lighting are shown in table 1.
6. Probabilities of occurance in the half part of the aqualium more than or less than n individuals among 10 individuals when they are scattered by chance are shown in table 2.
7. Probabilities of occurance of more than or less than n individuals in each three sub-part when the total number of individuals in the beam are scattered by chance are shown in table 3.
8. I wish to recognize the positive influence of the light upon the distribution of fishes when the probability of occurance less than the number of individuals actually observed in the dark half among 10 individual is less than 0.05 or when probability of occurance of individuals more than actually observed in the frontal sub-part is less than 0.05; the negative influence was desccrned in the case vice versa.
9. Influences of various lights appreciated on the above-mentioned criteria are summarized into table 4.
10. Frequency dstribution of number of individuals in sub-part is seems to be some exponential type.
11. Using analysis of variance on the values transformed into square root, it is clear that the difference of the light intensity causes the significant difference in the number of fishes in the frontal and middle sub-division of the illuminated half and in the other half of the aqualium, while the difference of the filter brings no significant change in the distribution of fishes.
