The components of such edible robots could be mixed with nutrient or pharmaceutical components for digestion and metabolization. Potential applications are disposable robots for exploration, digestible robots for medical purposes in humans and animals, and food transportation where the robot does not require additional payload because the robot is the food.
Fully edible robots would help to study how wild animals collectively behave. The robots could also take a role of animals prey to observe their hunting behaviors, or to train protected animals to do predation. Once medical components are mixed into the edible composition, the robots could help preservation of wild animals or heal inside of the human body. When edible robots can be metabolized, they also function as energy storage providing an advantage in terms of increased payload with respect to non-edible robots that must be loaded with a food payload. This would be effective in rescue scenarios where the metabolizable robots can reach survivors in isolated places like inside a crevice or up on mountain. Last, but not least, since edible materials can generate electric energy, one could envisage autophagy (self-eating) function, like that of octopus, to extend their lifetime.
Edible insects are an important source of food to many African populations. The longhorn grasshopper, Ruspolia differens (Serville 1838), commonly known as senene in Tanzania is one of the most appreciated edible insects by societies around Lake Victoria crescent. Senene is primarily an essential treat for the tribes around the lake, e.g., the Haya of Tanzania, Luo of Kenya and Baganda of Uganda. Despite its importance as a food item and appreciation as a delicacy, there are few studies dealing with culture, beliefs and indigenous technology in connection with the senene. The main objective of this study was to survey indigenous technologies, processing methods and traditions in relation to senene consumption among the Haya tribe in Kagera region of Tanzania.
Anthropo-entomophagy is spreading globally . Although not fully embraced by the majority of Western cultures, consumption of edible insects by humans (anthropo-entomophagy) has existed since ancient times [2, 3]. In developed countries like Japan and Korea, the grasshopper, Oxya yezoensis , remains popular as an edible species and globally, Orthoptera like grasshoppers and katydids, e.g., Ruspolia differens , locusts like Locusta migratoria  and crickets  play a major role among the more than 2000 species currently considered edible .
Senene has been widely harvested and consumed as a traditional snack in Zambia and regions around Lake Victoria crescent including Tanzania, Uganda, Kenya and Democratic Republic of Congo. In these areas, indigenous people customarily consider senene and other edible insects to be highly nutritious and believe they have specific medicinal properties. The culture of senene consumption is indigenous to the Haya tribe found in the Lake zone of Tanzania, where the offering of senene is seen as a sign of respect to the person it is served to. This culture has now spread throughout Tanzania where senene is commercially available and widely consumed by different tribes. Senene is reported to be nutritious consisting of 44% protein and with good ratios of essential amino acids [10, 11, 16, 17]. It is known for its high fat content, with high composition of essential fatty acids, up to 16% of α-linolenic acid . Senene is also rich in vitamins and minerals with higher nutrients bioavailability compared to most plants; up to 2.12 mg/g vitamin A, 0.99 mg/100 g folate, 2 to 16.6 mg/100 g iron and 17 mg/100 g zinc have been reported .
Cleaning was done to remove inedible body parts namely wings, appendages and ovipositor for female senene (Fig. 4). Wood ashes are used to increase friction and ease the process. Antennae, which are slippery and light, were often not removed as they disappeared within processing chain. At this stage, other insects collected with the senene as well as grasses and other waste materials are removed. Some reported washing with cold water before further processing; however, some did not wash claiming that washing would drain out fat and make senene less enjoyable.
The use of edible insects in addressing malnutrition has been evaluated by several researchers [28,29,30,31,32,33,34]. Silkworm pupae were included among essential ingredients for supplementary food to malnourished children in Congo . Edible insects have also been utilised to enrich plant-based complementary foods. In Kenya, winged termites were used to enrich amaranth-based complementary foods  while in Cambodia, edible spiders were utilised to enrich a rice-based complementary food .
In Uganda, the grasshopper trade is characterised by wholesalers who buy grasshoppers from collectors and sell to retailers, who sell to consumers around Kampala . The edible insects business is growing globally as the market for edible insects collected in the wild as well as reared in captivity increases . For example, Belgium annually imports up to three tonnes and France five tonnes of dried mopane caterpillar from the Democratic Republic of Congo and Zambia [9, 29].
As early as 1975, edible insects were advocated as a food item to stave off malnutrition , but in order to get maximum benefit from senene as a food item, improvements to the indigenous processing technology are required to assure quality and safety of marketed senene. Promotion of senene as a delicious food among all consumers should be encouraged in order to tackle the challenges posed by limiting taboos. Inclusion of senene in the diets of infants and young children is a subject which requires attention of the researchers. Studies on environmental friendly ways to raise senene in captivity will increase the year round availability of this currently seasonal delicacy. Shelf-life studies on the senene processed by different methods are needed.
Edible insects are found in agricultural systems worldwide, and are an important source of food and income. However, many edible insects are also pests of important food crops, which raises the question of how far their presence might be costly to farmers in terms of reduced crop yields. In this study we aimed to understand the impact of defoliation of shea trees by edible caterpillars on yields of shea and maize in a mixed agroforestry system in Burkina Faso, West Africa. We collected field data in two consecutive years. Our results suggest that tree defoliation by caterpillars has no effect on shea fruit yields, and that defoliation may have a positive effect on maize productivity. We conclude that this appears to be an example of an agricultural system in which nutritionally and economically important plants and insects are both harvested by humans without risking yield reductions of harvested plants.
Wild-harvested edible insects are an important source of food and income across much of the world (Van Huis et al. 2013). This is particularly true in sub-Saharan Africa, where termites, locusts and caterpillars are traded and consumed, mostly in rural but also in urban areas (Kelemu et al. 2015; Illgner and Nel 2000). Edible insects are often harvested from agricultural systems. In many cases, this is because insects that feed on crop plants are deliberately collected as food (DeFoliart 1992; Van Itterbeeck and Van Huis 2012). For example, palm weevil larvae are harvested from many palm-based agroforestry systems worldwide (Binnqüist and Shanley 2004), and weaver ants are harvested from fruit tree plantations in Southeast Asia (Payne and Van Itterbeeck 2017).
Other insects are harvested only at a specific point in their life cycle. Caterpillars are a good example of this: many are eaten only when in their final larval stage. This is the case for the mopane worm (Imbrasia belina), which is an economically important edible caterpillar throughout southern Africa (Ghazoul et al. 2006). The same is true for termite (Macrotermes spp.) alates, harvested after their nuptial flight, which occurs in response to the first rains (Kinyuru et al. 2013). These insects are found in abundance, but only when in season. However, most are wild-harvested, and are not found in agricultural fields. Many larval insects feed on crops, but are small in size and not traditionally eaten.
This is the first field study of the interaction between crop yields and the presence of an edible insect that is harvested at a single point in its life cycle. Unlike edible orthopteran pests, the shea caterpillars studied here do not have a discernible negative effect on crop yields. Instead, this insect does not appear to damage production of these economically important plants. We conclude that this appears to be an example of an agricultural system in which humans, as predators of both the plants and the insects in the system, are able to benefit in terms of harvesting both plant and animal matter without an apparent trade-off between the two.
Edible insects are important for the livelihoods of smallholder farmers worldwide (Payne and Van Itterbeeck 2017; Kelemu et al. 2015, Van Huis et al. 2013; Hanboonsong et al. 2013), and these results provide an optimistic framework for their sustainable exploitation under certain circumstances. However, the sustainability of the shea nut-caterpillar-maize system may be threatened by external factors. The market for edible insects is changing rapidly, with demand increasing among wealthier populations (Global Market Insights 2018; Payne 2014; Durst and Shono 2010). The climate is also changing, with increasing aridity in our study region and consequent decreases in crop productivity (Sonwa et al. 2017; Serdeczny et al. 2017). This may lead to management decisions that explicitly prioritise either the insects or the plants, shifting away from the current system. If this does happen, u