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Amber contains numerous well-preserved adult aquatic insects (e.g., aquatic beetles – Coleoptera, water bugs – Heteroptera, dragonflies – Odonata, caddisflies – Trichoptera, mayflies – Ephemeroptera, stone flies – Plecoptera). Since amber is fossilised resin of terrestrial conifer trees, it is an enigma how aquatic insects have ended up in the resin. Based on field studies in a Hungarian forest along a freshwater creek we suggest that tree resin traps water-seeking flying polarotactic aquatic insects because of its property to polarise reflected light. The sticky tree resin was modelled by a water-proof, transparent, colourless insect-monitoring glue laid on vertical and horizontal fallen tree trunks next to the creek. Adults of various polarotactic aquatic insect species were trapped only by the horizontal sticky trunk. In earlier field experiments we showed that these insects find water by means of the horizontal polarisation of water-reflected light, and therefore are attracted to and land on all surfaces which reflect horizontally polarised light. Using imaging polarimetry, we revealed the criterion of polarisation-based trapping by resiny tree trunks. According to our observations, flying aquatic insects can be trapped by sticky (resiny) regions of fallen tree trunks that reflect horizontally polarised light and thus attract polarotactic species. The resin continues to flow out of the trees even when fallen over or fractured in a storm. Our findings support and complement an earlier hypothesis, according to which amber-preserved adult aquatic insects have been trapped by resiny bark when they dispersed over land. [ABSTRACT FROM AUTHOR]

The article focuses on the findings of a study concerning the ultrastructural organisation of the eye of the Mediterranean slipper lobster Scyllarides latus. The study showed that the retina of the crustacean reacts to different ambient light intensities with photomechanical changes involving screening and reflecting pigments and that a circadian component controls full dark adaptation. It indicated that the extensive clear-zone in the eye of the slipper lobster suggests that the eye is suited for vision in a dimly lit environment and operates on the principle of reflecting superposition optics.

The aim of the present study was to examine mortality due to avoidable and unavoidable causes, unnatural deaths, and mortality possibly related to the use of psychotropic drugs. Mortality of 253 long-stay psychiatric patients from Northern Finland were monitored over a 9-year period and characterized according to standardized mortality rates (SMRs). Deaths due to avoidable causes included about 30% of all deaths, SMRs being 1.9 times (males) and 3.2 times (females) higher than those of the general population. The risk of unnatural deaths was also elevated, with SMRs amounting to 3.9 in males and 8.5 in females. An increased mortality risk, possibly related to the use of psychotropic drugs, was noticed. The physical care of long-stay psychiatric patients seems not to reach the same level that the general population enjoys. Continuous attention to the physical health of psychiatric patients is important, but new strategies and specific intervention methods should not be neglected. The concept of “avoidable mortality” is a useful, but rarely used indicator of the quality of the medical care in psychiatric populations. However, the concept needs regular updates from the whole field of medicine. From the psychiatric point of view, it was suggested that suicides be regarded as avoidable deaths. [ABSTRACT FROM AUTHOR]

Taxonomic identifications and vernacular names are given of insects as well as some spiders which are consumed as food by members of the following ethnic communities: Ao-Naga (North-east India), Chimbu (Papua New Guinea, Central Highlands), Onabasulu (Papua New Guinea, Southern Highlands), Kiriwina (Western Pacific, Trobriand Islands), Walbirl (Central Australian desert), Pintupi (Central Australian desert), and Maori (New Zealand, Aotearoa). Differences and similarities of entomophagy habits between the groups are examined in the light of cultural, ethnic, and linguistic relationships. It is postulated that prehistorically two centres in the region under discussion existed where entomophagy evolved and from where the practice spread: Southern India and South-east Asia. It is further postulated that the sugar-containing insects were the first to find a place in the regular diet of prehistoric man, followed by insects which were rich in fats and lipids, and finally those which contained mostly protein. According to thisscenario Australian Aborigines belong to the earliest group of insect eaters. Evidence is also presented that the domestication of the silk worm and the use of its product (i.e. silk) could have arisen fromthe practice of eating wild silkworm larvae and pupae in North-east India. Finally, a plea is made to fund research into the many uses ofinsects in traditional societies, before it is too late and such information is irretrievably lost. [ABSTRACT FROM AUTHOR]