Morphology and scaling of compound eyes in the smallest beetles (Coleoptera: Ptiliidae).

The coleopteran family Ptiliidae (featherwing beetles) includes some of the smallest insects known with most of the representatives of this family measuring less than 1 mm in body length. A small body size largely determines the morphology, physiology, and biology of an organism and affects the organization of complex sense organs. Information on the organization of the compound eyes of Ptiliidae is scarce. Using scanning electron microscopy we analyzed the eyes of representatives of all subfamilies and tribes and provide a detailed description of the eye ultrastructure of four species (Nephanes titan, Porophila mystacea, Nanosella sp. and Acrotrichis grandicollis) using transmission electron microscopy. The results are compared with available data on larger species of related groups of Staphyliniformia and scale quantitative analyses are performed. The eyes of Ptiliidae consist of 15-50 ommatidia 6-13 µm in diameter and all conform to the apposition acone type of eye with fused rhabdoms of banded organization. Each ommatidium has the typical cellular arrangement present also in the eyes of larger staphyliniform beetles, but strongly curved lenses, short cones, reduced pigment cells, a high density of pigment granules and certain modifications of the rhabdom seem typical of ptiliid eyes. Allometric analyses show that as body size decreases, the number of facets drops more steeply than their average size does.

A comparison between the larval eyes of the dimly luminescent Keroplatus nipponicus and the brightly luminescent Arachnocampa luminosa (Diptera; Keroplatidae).

Larvae of the weakly blue-luminescent fungus gnat Keroplatus nipponicus possess on either side of their heads a small black stemmatal eye with a plano-convex lens approximately 25 µm in diameter. In total, 12-14 retinula cells give rise to a centrally fused rhabdom of up to 8 µm in diameter. The rhabdom's constituent microvilli, approximately 70 nm in width, are roughly orthogonally oriented, a requirement for polarization sensitivity. Screening pigment granules are abundant in the retinula cells and measure at least 1 µm in diameter. In comparison with the stemmatal eye of the brightly luminescent Arachnocampa luminosa, that of K. nipponicus is considerably smaller with a poorer developed lens and a rhabdom that is less voluminous, but possesses wider microvilli. Although the larval eye of K. nipponicus can be expected to be functional, as the larvae react to light with a behavioural response, the eyes are probably mainly involved in the detection of ambient light levels and not, as in A. luminosa, also in responding to the luminescence of nearby conspecifics.

Therapeutic arthropods and other, largely terrestrial, folk-medicinally important invertebrates: a comparative survey and review.

Traditional healing methods involving hundreds of insect and other invertebrate species are reviewed. Some of the uses are based on the tenet of "similia similibus" (let likes be cured by likes), but not all non-conventional health promoting practices should be dismissed as superstition or wishful thinking, for they have stood the test of time. Two questions are addressed: how can totally different organ systems in a human possibly benefit from extracts, potions, powders, secretions, ashes, etc. of a single species and how can different target organs, e.g. bronchi, lungs, the urinary bladder, kidneys, etc. apparently respond to a range of taxonomically not even closely related species? Even though therapeutically used invertebrates are generally small, they nevertheless possess organs for specific functions, e.g. digestion, gas exchange, reproduction. They have a nervous system, endocrine glands, a heart and muscle tissue and they contain a multitude of different molecules like metabolites, enzymes, hormones, neurotransmitters, secretions, etc. that have come under increased scientific scrutiny for pharmacological properties. Bearing that in mind it seems likely that a single species prepared and used in different ways could have a multitude of uses. But how, for example, can there be remedies for breathing and other problems, involving earthworms, molluscs, termites, beetles, cockroaches, bugs, and dragonflies? Since invertebrates themselves can suffer from infections and cancers, common defence reactions are likely to have evolved in all invertebrates, which is why it would be far more surprising to find that each species had evolved its own unique disease fighting system. To obtain a more comprehensive picture, however, we still need information on folk medicinal uses of insects and other invertebrates from a wider range of regions and ethnic groups, but this task is hampered by western-based medicines becoming increasingly dominant and traditional healers being unable and sometimes even unwilling to transmit their knowledge to the younger generation. However, collecting and uncontrolled uses of therapeutic invertebrates can put undue pressure on certain highly sought after species and this is something that has to be borne in mind as well.

Common sense: folk wisdom that ethnobiological and ethnomedical research cannot afford to ignore.

Common sense [CS], especially that of the non-scientist, can have predictive power to identify promising research avenues, as humans anywhere on Earth have always looked for causal links to understand, shape and control the world around them. CS is based on the experience of many individuals and is thus believed to hold some truths. Outcomes predicted by CS are compatible with observations made by whole populations and have survived tests conducted by a plethora of non-scientists. To explore our claim, we provide 4 examples of empirical insights (relevant to probably all ethnic groups on Earth) into causal phenomena predicted by CS: (i) "humans must have a sense of time", (ii) "at extreme latitudes, more people have the winter blues", (iii) "sleep is a cure for many ills" and (iv) "social networks affect health and disease". While CS is fallible, it should not be ignored by science - however improbable or self-evident the causal relationships predicted by CS may appear to be.

Comparative survey of entomophagy and entomotherapeutic practices in six tribes of eastern Arunachal Pradesh (India).

A consolidated list of edible insects used in the eastern part of Arunachal Pradesh (N.E. India) by Wangcho (Wancho) and Nocte tribes of the Tirap District and the Shingpo, Tangsa, Deori and Chakma of the Changlang District has been prepared. The list is based on thorough, semi-structured field-interviews with 20 informants of each tribal group. At least 51 insect species, belonging to 9 orders were considered edible. The largest number of the edible species belonged to the Coleoptera (14), followed by 10 each of the Orthoptera and Hymenoptera, 9 of the Hemiptera, 3 Lepidoptera, 2 Isoptera and one each of Ephemeroptera, Odonata and Mantodea. As far as therapeutic uses of insects are concerned, 4 species (Hemiptera) were mentioned by the Wangcho (Wancho). Food insects are chosen by members of the various tribes according to traditional beliefs, taste, regional and seasonal availability of the insects. Depending on the species, only certain, but sometimes all, developmental stages are consumed. Preparation of the food insects for consumption involves mainly roasting or boiling. With the degradation of natural resources, habitat loss, rapid population growth, and increasing 'westernization' , the traditional wisdom of North-East Indian tribals related to insect uses is at risk of being lost.

Ethno-entomological observations from North Korea (officially known as the "Democratic People's Republic of Korea").

In terms of scientific activities generally and ethnobiological pursuits in particular, North Korea, officially known as the Democratic People's Republic of Korea, is an almost blank entity on the quilt of global research. During a sabbatical semester at Pyongyang University of Science and Technology the author used this opportunity to gather some information on the uses of insect and other terrestrial arthropods as human food and components of traditional healing methods in that country. Despite the widely publicised shortcomings in the supply of food stuffs to the population of North Korea, insects are not generally seen as a source of food worthy of exploitation. However, the therapeutic use of insects, centipedes and scorpions to treat illnesses as diverse as the common cold, skin rashes, constipation, dysentery, nervous prostration, whooping cough, osteomyelitis, tetanus, and various forms of cancer is apparently still popular. The arthropods used therapeutically are credited with anti-inflammatory, immunological and other health-promoting effects, because they are said to contain hormones, steroids, lipids and plant-derived alkaloids, all of which capable of exerting their effects on the human body.

What do we know 40 years after Nixon declared the 'war on cancer'? On the origin, prevention and treatment of cancer.

Evolutionary principles suggested by Darwin and Wallace some 150 years ago can provide insights into the origins of cancer. Moreover, they can form a basis for answering the question implicitly posed when Nixon declared the war on cancer in 1971: Can we actually 'cure' cancer? As explained lucidly by Greaves in 2001, necessary keys to evolution and thus for the origin of species, including ours, are changes of genes or mutations; but changes of genes are also necessary links in the causal chains which lead to cancer. In effect, cancer is therefore, according to Greaves, an 'evolutionary legacy'. Intriguingly, the realization that cancer is a consequence of changes in genes which are conditiones sine qua non for evolution suggests a mutation paradox on an evolutionary scale: in individuals, mutations may have devastating adverse health effects, including cancer. Populations, however, as a whole can be expected to benefit ultimately from changes of genes to better adapt to environmental challenges. On the basis of premises from evolution theory, it remains for us to interweave growing insights into evolutionary principles with realistic objectives for the primary prevention of and, where the latter fails, coexistence with cancer so that what we do for patients can become more of an art rather than a war.

Challenging limits: ultrastructure and size-related functional constraints of the compound eye of Stigmella microtheriella (Lepidoptera: Nepticulidae).

With a body length of only 2 mm, the nepticulid Stigmella microtheriella (Stainton, 1854) is one of the smallest moths known to date. We investigated the optical design of its lemon-shaped compound eyes, which measure 83.60 µm in anterior-posterior and 119.77 µm in dorso-ventral direction. The eyes consist of about 123 facets, each of the latter just 9.9 µm in diameter. Transmission electron microscopy reveals an optical design with features intermediate between apposition and superposition optics similar to that known from two other small species of moths (one Nepticulid and one Gracillarid). Size-related evolutionary adaptations of the ommatidial organization include (1) the involvement of only five rhabdomeres in the formation of the distal rhabdom (2) the complete absence of a rhabdomere of the eighth (= basal) retinula cell, (3) the "hourglass" shape of the rhabdom with a characteristic narrow waist separating distal from proximal portion, and (4) the reduction to one single layer of tracheoles as an adaptation to the overall restricted space available in this minute eye.

A possible role of perinatal light in mood disorders and internal cancers: reconciliation of instability and latitude concepts.

Thought-provoking experimental evidence suggests that perinatal light exposure may imprint circadian clocks with lasting effects on the alignment and the stability of circadian rhythms later in life. Assuming that exposure to light early in life could determine the stability of an individual's circadian system later in life, the present hypothesis proposes that time of year and location of birth (i.e., season and latitude) and thus differential Zeitgeber strengths may be key contributors to a person's susceptibility of developing mood disorders like seasonal affective disorder (SAD) and common internal cancers such as those of breast and prostate. Consequently, when and where people are born might critically predispose them to both mood disorders and internal cancers, and may affect the onset and course of such illnesses. This paper develops a causal framework and presents suggestions for rigorous tests of the associated corollary and predictions. It does not escape our attention that links between the perinatal Zeitgeber strength of light and its effects on the stability of circadian systems later in life could have a role to play in affecting long-term health beyond cancer and mood disorders - mostly in adults but also in children.

A perinatal signature of light on chronobiology? If so, numerous questions arise and experimental animal research must provide more information.

That light and melatonin rhythms provide both clock and calendar information in humans and numerous other species is beyond dispute; this holds true for all stages of life, including the very early ones. Experimental evidence elucidates that exposure to light and melatonin titres are keys for the very development of circadian and seasonal rhythms. As evinced by a 2011 publication in Nature Neuroscience such awareness could impact considerably on the design and conduct of experimental studies as well as their subsequent analyses, interpretations and comparisons. Therefore "when and how experimental animals were bred, developed and raised" may be critical when experimenting with animals generally, and not just rodents. As long as the suggested imprinting of circadian system stability via light cues is not falsified, the perinatal season or perinatal experimental light:dark [L:D] conditions that an animal was kept under should be routinely recorded, published and considered in analysing and interpreting study data.

Studying nanostructured nipple arrays of moth eye facets helps to design better thin film solar cells.

Nipples on the surface of moth eye facets exhibit almost perfect broadband anti-reflection properties. We have studied the facet surface micro-protuberances, known as corneal nipples, of the chestnut leafminer moth Cameraria ohridella by atomic force microscopy, and simulated the optics of the nipple arrays by three-dimensional electromagnetic simulation. The influence of the dimensions and shapes of the nipples on the optics was studied. In particular, the shape of the nipples has a major influence on the anti-reflection properties. Furthermore, we transferred the structure of the almost perfect broadband anti-reflection coatings to amorphous silicon thin film solar cells. The coating that imitates the moth-eye array allows for an increase of the short circuit current and conversion efficiency of more than 40%.

Chemical composition of Aspongopus nepalensis Westwood 1837 (Hemiptera; Pentatomidae), a common food insect of tribal people in Arunachal Pradesh (India).

We identified nutritionally relevant fatty acids and macro- and micronutrient content in Aspongopus nepalensis Westwood 1837 (Hemiptera), an insect used as food by the ethnic people of Arunachal Pradesh (North East India). Regarding macronutrients, crude lipids made up 38.35 %, fibre 33.47 %, protein 10.6 %, moisture 41.9 %, and ash 2.1 %. Lipid amounts were higher than those of most other insects. A. nepalensis was rich in Na: 1.02 %, K: 0.35 %, Ca: 0.12 %, Mg: 0.16 % and moreover, contained considerable amounts of Fe, Cu, Zn, and Mn. With regard to vitamins, A was most abundant (34.38 µg/100 g); C, D, E, and those of the B-complex were present, but less abundant, and monounsaturated fatty acid (MUFA) content was high (56.1 % of the total fat). Oleic and palmitic acids (46.41 % and 32.32 % of total fat) were the two major fatty acids in this insect's oil. The latter also contained moderate amounts of stearic, palmitoleic, linoleic, myristic, eicosenoic, and linolenic acids.

Vertebrates used for medicinal purposes by members of the Nyishi and Galo tribes in Arunachal Pradesh (North-East India).

Arunachal Pradesh, the easternmost part of India, is endowed with diverse natural resources and inhabited by a variety of ethnic groups that have developed skills to exploit the biotic resources of the region for food and medicines. Information on animals and animal parts as components of folk remedies used by local healers and village headmen of the Nyishi and Galo tribes in their respective West Siang and Subansiri districts were obtained through interviews and structured questionnaires. Of a total of 36 vertebrate species used in treatments of ailments and diseases, mammals comprised 50%; they were followed by birds (22%), fishes (17%), reptiles (8%) and amphibians (3%). Approximately 20 common complaints of humans as well as foot and mouth disease of cattle were targets of zootherapies. Most commonly treated were fevers, body aches and pains, tuberculosis, malaria, wounds and burns, typhoid, smallpox, dysentery and diarrhoea, jaundice, and early pregnancy pains. Very few domestic animal species (e.g., goat and cattle) were used zootherapeutically. More frequently it was wild animals, including endangered or protective species like hornbill, pangolin, clouded leopard, tiger, bear, and wolf, whose various parts were either used in folk remedies or as food. Some of the animal-based traditional medicines or animal parts were sold at local markets, where they had to compete with modern, western pharmaceuticals. To record, document, analyze and test the animal-derived local medicines before they become replaced by western products is one challenge; to protect the already dwindling populations of certain wild animal species used as a resource for the traditional animal-derived remedies, is another.