With regard to the increase in SLA values from gaps to under the canopy, B. darwiini plants follow the typical intra-specific variation due to declining light availability (Poorter 1999; Valladares et al. 2000).
Throughfall variability, expressed as the coefficient of variation (CV) of throughfall, tended to decline with the increase in rainfall amount, intensity and duration, and stabilized passing a certain threshold.
For this formulation, there was no significant tendency for the residual variation in log lead concentration to decline with increasing pellet numbers (likelihood-ratio test; χ2 = 0.83, d.f. = 1, P = 0.363), so a constant residual standard deviation was estimated as 1.473.
But new research suggests another possibility: that harsh environmental conditions on the island--from variations in rainfall to declining soil quality--caused a decline, but not a collapse, in the native population before the Europeans arrived in 1722, Live Science reported.
He put it down to declining variation, and far from endorsing the myth that the champions of the past were greater and that standards have fallen, he showed how it proves the opposite - that the standard of the sport has improved.
Hawaiian honeycreepers are also a model to investigate the response of genetic variation to human caused population decline, fragmentation and founder effects.
For example, previous research with clonally reproducing zooplankton suggests that genetic variation, as well as the ratio of genetic variation to total phenotypic variation (i.e. heritability), can decline throughout the growing season as a result of clonal selection (Lynch 1984; Pfrender and Lynch 2000).
Following previous studies of clonal selection in other cladoceran zooplankton (e.g. Daphnia; Lynch 1984; Pfrender and Lynch 2000), we further predicted that genetic variation would decline throughout the growing season.
This finding is consistent with the analysis of DiBattista (2008), who reported that genetic variation typically declined in response to anthropogenic habitat fragmentation.
The peak-to-peak irradiance variation declined with increasing wavelength, reaching ∼10% just below the Al edge at 208 nm.
