Spider species acceptance of, and segregation by, architectural configuration was investigated for the spiders of Green Canyon in northern Utah, USA. Modular habitat units consisting of 30.48—cm (1—foot) cubes of chicken wire supporting internal strands of macrame jute tied in different orthogonal configurations were used. Configurations including all three axes were tested at two strand densities. The null hypothesis, that spiders use structures independent of architecture, was rejected in favor of the alternate hypothesis that spider species differentially use structures dependent upon architecture. Of the eight most abundant species, two showed preferences for horizontal substrata and one chose vertical substrata. All spiders strongly responded to the amount of jute available in each module. The two most abundant jumping spiders were biased toward modules with widely spaced jute, while the two most abundant web—builders preferred closely spaced jute.

Algae that have a low growth rate with a low mineral content are inferior foods for Daphnia growth, but these foods are not inferior for maintenance metabolism. The C per unit volume of low‐growth‐rate algal food necessary for zero body growth was similar to that of high‐growth‐rate food. Maintenance metabolism requires mainly energy, while body growth requires other essential substances; thus, they are separate influences of food quality.

Fifty—four communities were developed from repeated introductions of 28 phytoplankton species in three different orders of invasion at three different rates. Variation in species richness values in these communities was assignable to invasion order, invasion rate, and the timing between interspecific invasions. Invasion rate was most influential, explaining 21.8—78.8% of the variation on any give date; invasion order never explained >4.3%, and timing explained between 19.7 and 74.9%. All three facets of invasion had significant effects. One of the low—rate invasion categories developed a unique community structure that was dominated by Chlamydomonas. Communities in this category were invulnerable to the invasion of many species and as a result had low species richness values. The relative abundance patterns of species in categories having low or moderate invasion rates but identical invasion orders clustered more closely to each other than they did to their high invasion rate counterparts. In this sense, invasion order is more influential where immigration rates are relatively low (e.g., on islands) than it is where dispersal from outside sources is high (e.g., on continents). Because invasion history was controlled, the methodology used here provides interpretable data concerning the potential importance of chance historical events that occur during community assembly. The data indicate that idiosyncrasies in community structure often may be explained on the basis of the random invasion patterns of organisms to different habitats.

A central ethical issue confronting researchers using visual methods is how to manage the use of identifiable images. Photographic and other visual materials can make the anonymisation of individuals problematic; at the same time many researchers, as well as research participants, view image manipulation as undesirable. Anonymisation is one of a range of ethical concerns that need consideration in relation to the use of identifiable images. Other concerns include the contexts in which images were produced and through which they may be consumed, the longevity of images in the public domain and the potential for future uses and secondary analysis of images. This paper explores some of the ways in which researchers specifically approach anonymisation in relation to visual methods, drawing on a qualitative study of ethical issues in visual research. Focus group discussions and interviews with researchers who use visual methods revealed the ongoing challenges of identification and anonymisation. While decisions about visual identification are inevitably complex and situated, our explorations revealed ongoing tensions between, on the one hand, research participants' rights and researchers' desire for participants to be seen as well as heard and, on the other hand, researchers' real and perceived ethical responsibility to safeguard participants.

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