US researchers have combined tissues from a sea slug with flexible 3D printed components to build "biohybrid" robots that crawl like sea turtles on the beach. A muscle from the slug's mouth provides the movement controlled by an external electrical field. However, future iterations of the device will include ganglia - bundles of neurons and nerves that normally conduct signals to the muscle as the slug feeds, as an organic controller. The researchers also manipulated collagen from the slug's skin to build an organic scaffold to be tested in new versions of the robot. In the future, swarms of biohybrid robots could be released for such tasks as locating the source of a toxic leak in a pond that would send animals fleeing, the scientists say. Or they could search the ocean floor for a black box flight data recorder. "We're building a living machine - a bio-hybrid robot that's not completely organic ... yet," said Victoria Webster, a PhD student at Ohio's Case Western Reserve University, who is leading the research. Webster discussed mining the sea slug for materials and constructing the not quite 5cm long hybrid at the global Living Machines conference in Scotland this week.

In the house-hunting ant world, there's no such thing as a property crisis

Perhaps Aucklanders can learn a few things from ants. Ants employ a few simple and flexible rules to ensure that moving a colony to a new nest does not end in chaos, especially if this is done over some distance. Researchers often use the house-hunting ant, Temnothorax albipennis, to investigate the migration strategies and behaviour of social insect colonies. Research has shown that house-hunting ants use so-called "tandem running" to inform colony members about an imminent move to a new nest, and to ensure the continuity and speed of the subsequent migration. Once a certain number of ants are introduced to a new site, a so-called quorum threshold is reached, signalling that the colony has made its decision. After this point, the slow tandem running phase is replaced by the much faster social carrying phase, in which workers transport eggs, larvae and pupae rapidly to the safety of the new nest.

House-hunting ants use
House-hunting ants use "tandem-running" when moving to a new nest. Photo / Thomas O'Shea-Wheller

Can chickens protect you from malaria?


For the first time, scientists have shown that malaria-transmitting mosquitoes actively avoid feeding on certain animal species such as chickens, using their sense of smell - findings that could offer an interesting new safeguard to the infectious disease. Researchers from Sweden and Ethiopia found that Anopheles arabiensis, one of the predominant species transmitting malaria in sub-Saharan Africa, avoids chickens when looking for hosts to feed on. This indicates that chickens are a non-host species for An. arabiensis and that the mosquitoes have developed ways of distinguishing them from host species. "We were surprised to find that malaria mosquitoes are repelled by the odours emitted by chickens," study co-author Professor Richard Ignell said. "This study shows for the first time that malaria mosquitoes actively avoid feeding on certain animal species, and that this behaviour is regulated through odour cues."