The purpose of this study was to identify and compare the afferent projections to the primary visual cortex in intact and enucleated C57BL/6 mice and in ZRDCT/An anophthalmic mice. Early loss of sensory-driven activity in blind subjects can lead to activations of the primary visual cortex by haptic or auditory stimuli. This intermodal activation following the onset of blindness is believed to arise through either unmasking of already present cortical connections, sprouting of novel cortical connections or enhancement of intermodal cortical connections. Studies in humans have similarly demonstrated heteromodal activation of visual cortex following relatively short periods of blindfolding. This suggests that the primary visual cortex in normal sighted subjects receives afferents, either from multisensory association cortices or from primary sensory cortices dedicated to other modalities. Here cortical afferents to the primary visual cortex were investigated to determine whether the visual cortex receives sensory input from other modalities, and whether differences exist in the quantity and/or the structure of projections found in sighted, enucleated and anophthalmic mice. This study demonstrates extensive direct connections between the primary visual cortex and auditory and somatosensory areas, as well as with motor and association cortices in all three animal groups. This suggests that information from different sensory modalities can be integrated at early cortical stages and that visual cortex activations following visual deprivations can partly be explained by already present intermodal corticocortical connections.

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Simulium laciniatum Edwards, 1924 is endemic to Fiji and is also the only known black fly species in the Fiji archipelago, a most unusual situation since neighbouring Vanuatu harbours fourteen precinctive species from the same subgenus, Hebridosimulium Grenier & Rageau, 1961. Morphology indicates that S. (H.) laciniatum is monospecific throughout the Fiji archipelago, so the species was further scrutinised from a molecular standpoint. Samples taken from five islands of Fiji show a major lack of heterogeneity in the mitochondrial COII gene and a probable date around 105 years has been inferred for the S. (H.) laciniatum ancestor, a likely migrant from Vanuatu. COII homogeneity may also reflect the dispersal abilities of blood-seeking females of this species, abetted possibly by shortened distances between islands during ice ages concurrent with depressed sea levels. However, the ITS1 spacer between the 18S and 5.8S rDNA genes exhibits six haplotypes, with the two predominant ones clearly arrayed in a north–south distribution. This suggests sufficient distance between suites of islands in recent times to allow precinctive population development.