Plants were grown individually in pots without root competition, and size variability was limited, which was different from plants growing in the field (e.g. Nagashima et al., 1995).
The broader approach taken here, considering several possible factors affecting colony demography and not testing each one in isolation, shows that competition and environmental variability can have a similar strong impact on demography and life-history of hosts.
Water demand and climate variability increases competition and tension between water users –agricultural, industrial, mining, hydropower– and local communities.
Bonobos, they wrote, are accustomed to a more plentiful food environment, while chimpanzees face greater seasonal variability and competition for food.
The greatest threats to current whale populations are likely mortality due to ship strikes [41] and potentially reduced food supplies due to climate variability or competition with humans [42].
For instance, more intensive within-sex competition could reduce genetic variability in males more than in females (see [ 8]).
Factors that are not considered in the model that may contribute to the variability include competition between interventions in the same class, the relative strength of marketing, and the effects of a highly dynamic evidence-base supporting the comparative effectiveness of medicines in each class.
Basic concepts related to genetics, mutation, genetic variability, carrying capacity, competition, migration, natural selection, and random genetic drift should be introduced before the exercise starts.
To help interpret competition effects, trends in the variability of competition to which trees at each site were subject were also determined by calculating the coefficient of variation (CV %) of the competition index.
The variation can be driven by a number of factors, including colony size and thus intraspecific competition [ 53] and oceanographic variability [ 54].
