Predators of highly defensive prey likely develop cost-reducing adaptations. The ant Megaponera analis is a specialized termite predator, solely raiding termites of the subfamily Macrotermitinae (in this study, mostly colonies of Pseudocanthotermes sp.) at their foraging sites. The evolutionary arms race between termites and ants led to various defensive mechanisms in termites (for example, a caste specialized in fighting predators). Because M. analis incurs high injury/mortality risks when preying on termites, some risk-mitigating adaptations seem likely to have evolved. We show that a unique rescue behavior in M. analis, consisting of injured nestmates being carried back to the nest, reduces combat mortality. After a fight, injured ants are carried back by their nestmates; these ants have usually lost an extremity or have termites clinging to them and are able to recover within the nest. Injured ants that are forced experimentally to return without help, die in 32% of the cases. Behavioral experiments show that two compounds, dimethyl disulfide and dimethyl trisulfide, present in the mandibular gland reservoirs, trigger the rescue behavior. A model accounting for this rescue behavior identifies the drivers favoring its evolution and estimates that rescuing enables maintenance of a 28.7% larger colony size. Our results are the first to explore experimentally the adaptive value of this form of rescue behavior focused on injured nestmates in social insects and help us to identify evolutionary drivers responsible for this type of behavior to evolve in animals.

An efficient foraging strategy is one of the most important traits for the fitness of animals. The theory of optimal foraging tries to predict foraging behaviour through the overarching question: how animals should forage so as to minimize costs while maximizing profits? Social insects, having occupied nearly every natural niche through widely different strategies, offer themselves as an ideal group to study how well optimal foraging theory can explain their behaviour and success. Specialization often leads to unique adaptations in morphology and behaviour. I therefore decided to investigate the behaviour of Megaponera analis. This ponerine ant species is specialized on hunting only termites of the subfamily Macrotermitinae at their foraging sites. Their foraging behaviour is regulated by a handful of individual scouts (10-20) that search for termite foraging sites before returning to the nest to recruit a large number of nestmates (200-500 ants). These ants then follow the scout in a column formation to the termites and after the hunt return together to the nest, these raids occur two to five times per day. Predators of highly defensive prey likely develop cost reducing adaptations. The evolutionary arms race between termites and ants led to various defensive mechanisms in termites, e.g. a caste specialized in fighting predators. As M. analis incurs high injury/mortality risks when preying on termites, some risk mitigating adaptations have evolved. I show that a unique rescue behaviour in M. analis, consisting of injured nestmates being carried back to the nest, reduces combat mortality. These injured ants “call for help” with pheromones present in their mandibular gland reservoirs. A model accounting for this rescue behaviour identifies the drivers favouring its evolution and estimates that rescuing allows for maintaining a 29% larger colony size. Heavily injured ants that lost too many legs during the fight on the other hand are not helped. Interestingly, this was regulated not by the helper but by the uncooperativeness of the injured ant. I further observed treatment of the injury by nestmates inside the nest through intense allogrooming directly at the wound. Lack of treatment increased mortality from 10% to 80% within 24 hours, with the cause of death most likely being infections. Collective decision-making is one of the main mechanisms in social insects through which foraging is regulated. However, individual decision-making can also play an important role, depending on the type of foraging behaviour. In M. analis only a handful of individuals (the scouts) hold all the valuable information about foraging sites. I therefore looked at predictions made by optimal foraging theory to better understand the interplay between collective and individual decision-making in this obligate group-raiding predator. I found a clear positive relation between raid size and termite abundance at the foraging site. Furthermore, selectivity of the food source increased with distance. The confirmation of optimal foraging theory suggests that individual scouts must be the main driver behind raid size, choice and raiding behaviour. Therefore most central place foraging behaviours in M. analis were not achieved by collective decisions but rather by individual decisions of scout ants. Thus, 1% of the colony (10–20 scouts) decided the fate and foraging efficiency of the remaining 99%. Division of labour is one of the main reasons for the success of social insects. Worker polymorphism, age polyethism and work division in more primitive ants, like the ponerines, remain mostly unexplored though. Since M. analis specializes on a defensive prey, adaptations to reduce their foraging costs can be expected. I found that the work division, task allocation and column-formation during the hunt were much more sophisticated than was previously thought. The column-formation was remarkably stable, with the same ants resuming similar positions in subsequent raids and front ants even returning to their positions if displaced in the same raid. Most of the raid tasks were not executed by predetermined members of the raid but were filled out as need arose during the hunt, with a clear preference for larger ants to conduct most tasks. I show that specialization towards a highly defensive prey can lead to very unique adaptations in the foraging behaviour of a species. I explored experimentally the adaptive value of rescue behaviour focused on injured nestmates in social insects. This was not only limited to selective rescuing of lightly injured individuals by carrying them back (thus reducing predation risk) but moreover includes a differentiated treatment inside the nest. These observations will help to improve our understanding of the evolution of rescue behaviour in animals. I further show that most optimal foraging predictions are fulfilled and regulated by a handful of individuals in M. analis. Lastly, I propose that the continuous allometric size polymorphism in M. analis allows for greater flexibility in task allocation, necessary due to the unpredictability of task requirements in an irregular system such as hunting termites in groups. All of my observations help to further understand how a group-hunting predator should forage so as to minimize costs while maximizing profits.

A new innovative satellite mission, the Innovative CubeSat for Education (InnoCube), is addressed. The goal of the mission is to demonstrate “the wireless satellite”, which replaces the data harness by robust, high-speed, real-time, very short-range radio communications using the SKITH (SKIpTheHarness) technology. This will make InnoCube the first wireless satellite in history. Another technology demonstration is an experimental energy-storing satellite structure that was developed in the previous Wall#E project and might replace conventional battery technology in the future. As a further payload, the hardware for the concept of a software-based solution for receiving signals from Global Navigation Satellite Systems (GNSS) will be developed to enable precise position determination of the CubeSat. Aside from technical goals this work aims to be of use in the teaching of engineering skills and practical sustainable education of students, important technical and scientific publications, and the increase of university skills. This article gives an overview of the overall design of the InnoCube.