Stream hierarchy defines riverscape genetics of a North American desert fish

Global climate change is apparent within the Arctic and the south‐western deserts of North America, with record drought in the latter reflected within 640 000 km² of the Colorado River Basin. To discern the manner by which natural and anthropogenic drivers have compressed Basin‐wide fish biodiversity, and to establish a baseline for future climate effects, the Stream Hierarchy Model (SHM) was employed to juxtapose fluvial topography against molecular diversities of 1092 Bluehead Sucker (Catostomus discobolus). MtDNA revealed three geomorphically defined evolutionarily significant units (ESUs): Bonneville Basin, upper Little Colorado River and the remaining Colorado River Basin. Microsatellite analyses (16 loci) reinforced distinctiveness of the Bonneville Basin and upper Little Colorado River, but subdivided the Colorado River Basin into seven management units (MUs). One represents a cline of three admixed gene pools comprising the mainstem and its lower‐gradient tributaries. Six others are not only distinct genetically but also demographically (i.e. migrants/generation <9.7%). Two of these (i.e. Grand Canyon and Canyon de Chelly) are defined by geomorphology, two others (i.e. Fremont‐Muddy and San Raphael rivers) are isolated by sharp declivities as they drop precipitously from the west slope into the mainstem Colorado/Green rivers, another represents an isolated impoundment (i.e. Ringdahl Reservoir), while the last corresponds to a recognized subspecies (i.e. Zuni River, NM). Historical legacies of endemic fishes (ESUs) and their evolutionary potential (MUs) are clearly represented in our data, yet their arbiter will be the unrelenting natural and anthropogenic water depletions that will precipitate yet another conservation conflict within this unique but arid region.     

Epinephrine-induced pigment aggregation in goldfish melanophoroma cells: apparent involvement of an unknown second messenger

Using a goldfish-derived melanized cell line, we attempted to determine the identity of the signal transduction system/second messenger for epinephrine-induced aggregation of melanosomes in a goldfish cell line. The results show that the second messenger is unknown. It is not 1) influx of extracellular calcium, 2) release of intracellular stored calcium via the phosphoinositide pathway, 3) cGMP, or 4) decrease of cAMP. These results suggest that there is an unknown second messenger for this activity of epinephrine.     

Drinking Money and Pulling Women: Mobile Phone Talk,Gender, and Agency in Vanuatu

This paper examines aspects of gendered discourse around mobile phones in Vanuatu, focusing especially on the talk of high-ranking men from the northern Raga-speaking region of Pentecost Island. Rather than being restricted to the technologies or their direct capacities alone, it is argued that the local reception of new technologies such as mobile phones should be contextualised in terms of broader dialogues of change, and should also take into account the visual and discursive expressions of culture that accompanies them, including in the form of marketing. Examination of the ‘impact’ of such new technologies should also include taking account of broader local meanings and messages that become associated with them. As the ethnography presented here suggests, while mobile phones themselves certainly provide a useful tool for furthering positive social change, such as in the empowerment of women, the meanings and narratives that surround them may by marked contrast entail more negative entrenchments of unequal relations of power.