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The historical canalization of the Mfolozi River resulted in the St Lucia Estuary losing its main freshwater source. This, combined with the recent drought, led to low water levels, hypersaline conditions and dramatic losses in biodiversity. The excavation of a beach spillway between the estuary and the Mfolozi River mouth in 2012, combined with the commencement of a wet phase in the preceding year, has alleviated the freshwater deprivation crisis. This study compares the meso-zooplankton composition within the channel on both flood and ebb tides, providing a preliminary understanding of the role of the Mfolozi channel in the migration and recruitment of organisms. Abundance was higher on ebb tides, while species richness was higher on flood tides. A total of 53 zooplankton taxa were recorded in the channel. Of these, one had never been recorded in St Lucia before, namely the gastropod Pterotrachea cf. hippocampus. Additionally, the ctenophore Pleurobrachia cf. pileus and the mysid Gastrosaccus gordonae were again recorded for the first time since the late 1970s. Results show that the beach spillway has facilitated recruitment into St Lucia from the ocean and the Mfolozi River. Further research is needed to ascertain what effect this recruitment has on long-term zooplankton community structure.

Stomach-content analyses and laboratory experiments on Pleurobrachia pileus (Cydippida) showed an average digestion time of 2.0 h at 12°C and a high potential predation rate with highest daily ration in terms of prey carbon ingested as percent of predator body carbon for the calanoid copepod Calanus finmarchicus, the biggest prey tested Predation rate increased almost linearly with increased prey abundance over the whole range tested (12-1043 I−1 in start concentration) of mainly small-sized copepods. Tests of the importance of prey size showed an individual clearance rate of 6.1 1 day−1 with Calanus prey alone, which was depressed to 29 % of this when smaller prey was also present in high abundance. This is supposed to be an effect of handling time of prey in the feeding process. The laboratory results were used to estimate the impact of this species in Norwegian coastal waters. Abundance data were collected in summer from 56 stations between 63° and 69°N along a cruise track west of Norway. P. ...

Two scenarios of neuronal evolution (monophyly and polyphyly) are discussed in the historical timeline starting from the 19th century. The recent genomic studies on Ctenophores re-initiated a broad interest in the hypotheses of independent origins of neurons. However, even earlier work on ctenophores suggested that their nervous systems are unique in many aspects of their organization and a possibility of the independent origin of neurons and synapses was introduced well before modern advances in genomic biology.