It is well understood that more efficient decision making can be achieved if an agent holds estimates of uncertainty alongside the primary-information used to make a decision. Incorporating uncertainty into decision making would seem to be a sensible thing for insects to do, however there is little evidence to point to this. Perry and Barron address this issue by looking at the choices of bees in an opt-out paradigm. In this style of experiment, bees are rewarded for correct choices and punished for incorrect choices. Therefore, when the decision is difficult, an opportunity to opt-out may be adaptive. This paper reports that individual bees do indeed take the opt-out option in trials when a choice is difficult, thus suggesting that they are capable of monitoring uncertainty.
The exact mechanisms which lead to this behaviour are unclear. The authors discuss that it is hard to “[determine] whether simple invertebrates monitor uncertainty in decision making—or simply appear to do so”. This dichotomy seems to be questioning whether bees are using a cognitive strategy or not – which is of course an interesting question. But in some situations, “simply appearing to do something” is just the same as “doing something”. Understanding how apparent meta-cognition might emerge from the implementation of associative sensori-motor learning would be a valuable outcome and perhaps highlight the value of “bottom-up” approaches to animal cognition.
Perry, C. J., & Barron, A. B. (2013). Honey bees selectively avoid difficult choices. Proceedings of the National Academy of Sciences, 110(47), 19155-19159.
From behavioural studies we have been able to determine some of the general properties of how vision is used by navigating insects. However, the fine-grained sensori-motor implementation of visual strategies is less clear. Visual navigation presents interesting problems for walking ants in particular because their viewing direction is fixed relative to their long axis and therefore walking direction. Consequently, the characteristic wiggly path of an ant will lead to large changes in the ant’s view of the world, even if the ant’s path is direct overall. Lent et al. have looked at the fine details of this situation for wood ants navigating towards a visually defined goal. The wiggly/zigzag paths that the ants take toward the goal results in the ant reliably (but briefly) facing in the goal direction at the points of the zigzag where ants change turning direction. They find that the rapid saccade-like-turns (Lent et al. 2010, PNAS) that ants use to correct for errors in visually defined direction, are usually found in the same phase of the zigzag cycle as when ants would expect to be facing in the goal direction. Such phase-dependent use of vision shows how ants have organised their sensori-motor behaviour in such a way that they can still use a simple path control strategy.
Lent, D. D., Graham, P., & Collett, T. S. (2013). Phase-Dependent Visual Control of the Zigzag Paths of Navigating Wood Ants. Current Biology.
With radar technology we are able to track bees over reasonable distances and with that we can investigate how naive bees explore their environment prior to a foraging career. We have long know that in the vicinity of a goal bees will perform learning flights (aka turn back and look flights) whereby they inspect the surroundings of the goal. In addition to this bees perform orientation/survey flights where they inspect the environment over reasonable distances (but don’t forage). Data regarding these larger flights is rare and so any new data is invaluable. Here, Osborne et al. look at naive bumblebees and show path development with experience and discuss the similarities and differences with equivalent honeybee behaviour.
Studies of visually guided behaviour in insects have a long tradition of elucidating elegant computational strategies that demonstrate how task specific visual parameters can be directly extracted from the visual scene. Continuing in that tradition, Baird et al. show how bees use the apparent rate of expansion within a scene to reduce speed on approach to a landing event. Importantly, this strategy does not require knowledge of the speed of the bee or the distance to the surface. It also works without the bee having to stabilise orientation. As the authors also point out, this represents a universal strategy suitable for any flying agent landing on any surface.
Baird, E., Boeddeker, N., Ibbotson, M. R., & Srinivasan, M. V. (2013). A universal strategy for visually guided landing. Proceedings of the National Academy of Sciences, 201314311.
JAYATILAKA, P., RADERSCHALL, C. A., NARENDRA, A., & ZEIL, J. Individual foraging patterns of the jack jumper ant Myrmecia croslandi (Hymenoptera: Formicidae). Myrmecological News.
It is well known that insects are capable of complex learning tasks. One example being those behavioural experiments where the performance of insects (most often bees) can suggest that they have learnt an abstract rule to drive performance. It is this type of experiment which is reviewed here. The authors are putting the case for bees being able to learnt ‘concepts’, claiming that: “concepts such as ‘same’, ‘different’,‘above/below of’ or ‘left/right are well mastered by bees.” There is no doubt that these experiments demonstrate some wonderful behaviour. However, we are still quite far from understanding if this kind of behaviour in bees is based on homologous neural computations to the concept learning of vertebrates. And, it is still unclear how the “concept” learning of bees is built-on or driven-by ecological and foraging constraints. Of course, not knowing these things is what makes this topic so intriguing.
It is a well-versed fact that Path Integration is subject to cumulative error and that this explains the investment in learning other navigational cues. However, the nature of this cumulative error and its dependence on the information used by an animal is less clear. For a good few years Allen Cheung has investigated this question with cleverly put together analytical arguments. This paper continues that line of work by developing a general path and noise model which can be used to investigate the robustness of various components of the path integration system.
Navigation is not all about vision. Ants and honeybees are known to also rely on odors for guidance. Here the authors have investigated how odors and visual information interact in guiding the flight of foraging bees towards a feeding site by conducting a modern replication of Von Frisch’s ‘fan-shaped experiment’, but with the addition of harmonic radar tracking and wind monitoring.