. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. I 1 1 1 1 I 1 1 1 1 1 1 5 20 25 30 5 10 15 20 25 30 5 May June 1984 July FIGURE 8. The relative proportion of animals observed on a given high tide (top) corresponds to the relative height of the tide (bottom). The difference in proportion of animals is equal to the difference between the total number of animals observed on two semidiurnal high tides divided by the sum observed on both tides. Each point on the bottom graph represents the difference in heights of the pair of semidiurnal high tides in feet. A sinusoid with a p
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. I 1 1 1 1 I 1 1 1 1 1 1 5 20 25 30 5 10 15 20 25 30 5 May June 1984 July FIGURE 8. The relative proportion of animals observed on a given high tide (top) corresponds to the relative height of the tide (bottom). The difference in proportion of animals is equal to the difference between the total number of animals observed on two semidiurnal high tides divided by the sum observed on both tides. Each point on the bottom graph represents the difference in heights of the pair of semidiurnal high tides in feet. A sinusoid with a period of one lunar month ( days) and an amplitude of was fitted to the tidal data by eye. The same function shifted by days is plotted in the top half of the figure. the difference in tide height was small, as on 6 June, the degree of preference was small. But the correlation was not perfect. The sinusoidal function with a period of days that describes the tidal data in the bottom half of Figure 8 must be shifted to the right by days to fit the behavioral data. This shift implies a phase lag of nearly 3 days between changes in relative tide height and changes in the animals' preference for one tide over the other. Sunlight Mating activity was more strongly correlated with the tidal inequality than with light or darkness. For example, from 20 May to 3 June most animals (77%) migrated into the transects during the highest high tides indicated in Figure 5 by large arrows. These tides occurred from 1530 to 0330 h as shown by the stippled bars in Figure 9. Over this 15-day period half of the animals appeared in the transects during light (1530 to 2100 h) and half during darkness (2100 to 0330 h). We conclude that Limu- lus generally prefer to mate on the highest tides regardless of when they Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illu
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
