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Figure 3 | Frontiers in Zoology

Figure 3

From: Urban-like night illumination reduces melatonin release in European blackbirds (Turdus merula): implications of city life for biological time-keeping of songbirds

Figure 3

Relationship between melatonin and dawn activity. X-axis represents change in melatonin between midnight and either 6 am (winter, (a)) or 3 am (summer, (b)), Y-axis represents log-transformed mean activity counts in the hour preceding the onset of morning civil twilight (winter: 6:45, summer: 3:45). Dashed (light-at-night) and solid (dark night) black lines represent regression slopes from fitted linear models. Grey shaded areas represent 95% CI. For sample sizes and meaning of colours and symbols see Figure 1.

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