Figure 2 in Temperature variation and the presence of troglobionts in terrestrial shallow subterranean habitats

Figure 2. Top panel, temperature profiles at hourly intervals for an MSS site (black line) and nearby surface site (grey line) in a laurel forest in Teno in northwest Tenerife, Canary Islands (see Figure 1). Centre panel, spectral densities (y-axis) for different cycle periods (x-axis) for cycles up to 100 days for the surface site. Note the strong period at 24 hours. Bottom panel, spectral densities (y-axis) for different cycle periods (x-axis) for cycles up to 100 days for the MSS site. Note the absence of a 24 hour period even at very low spectral densities.