what are the two hypotheses that you might make about bees and flowers?

Question

biology

Answer 1

1.The diversity hypothesis is that the presence of a species of bee might depend on the presence of food plants of kinds not used by other bees, so that the species of bee is not excluded by competition. For example, Inouye (1977) applied this competition-based idea to bumblebees. He expected that there would be a higher diversity of bumblebees where there is a higher diversity of food plants, provided that there is a broad range of flower depths available. In Kent, at Dungeness where the diversity of bumblebees is highest in terms of numbers of bumblebee species, the diversity of food plants used is actually lower than at the species-poor site at Shoreham. This result, contrary to the diversity hypothesis, is obtained irrespective of whether food-plant diversity is measured (a) as the number of species of food-plants used; (b) as the range of flower depths used; or (c) as how evenly the bees shared their visits among the food plants (a more even sharing of visits would represent a pattern of more diverse flower use).

2.The abundance hypothesis is that the presence of a species of bee might be governed by the balance between local energy resources, in the form of food, and local energy 'costs', which are likely to be influenced by local climate. This is described by a simple model of distribution, which has been elaborated to account for the patterns described here (figure 6). It is based on the idea that the individuals of a species share a similar physiology that works better in a region with a near-optimum climate for that species (e.g. Andrewartha & Birch, 1954; Hengeveld & Haeck, 1981). Where the individuals find themselves a long way from this optimum, food availability may not always be sufficient to cover local 'costs', so that the species will not persist at every locality. Consequently, this model could account for the more patchy distributions of species nearer to the edges of their distributions. In Kent for instance, the bumblebee species nearer their distribution limits are also more patchy. Furthermore, a concentric pattern can be seen even within the British range of some species that are 'sub-central' here in their global distributions, such as B. lapidarius and B. ruderarius (see Alford, 1980 [maps] ). These species are nearly ubiquitous in south-eastern England, but are much more local in northern England, and reach their northern limits in Scotland. Yet the distribution patterns of some species are very patchy even in the central regions of their distributions. This can also be accounted for by the model, either if some widespread patches of habitat were to provide very little food, or if the species' range of tolerances on either side of the optimum were very narrow. The latter may be the case for some of the Southern Local Species in particular. Thus the model implies that locally abundant food could sometimes compensate for locally suboptimal climate for some species (Williams, 1985a, 1988).
http://www.nhm.ac.uk/research-curation/projects/bombus/decline.html

~faith