Understanding the Flight of the Bee

1. Key points in brief

• Bee flight relies on an integrated system: flexible wings, an elastic thorax, powerful muscles, fine-grained joints and rapid vision.
• The wings do not simply beat up and down: they move forwards and backwards, rotate, twist and exploit air vortices.
• The indirect flight muscles in the thorax provide the power output, while small steering muscles allow precise manoeuvres.
• Vision, in particular optic flow, helps the bee regulate its speed, altitude, landings and obstacle avoidance.
• At the apiary, the main benefit lies in better observation: understanding flight is not enough on its own to diagnose a colony, but it helps to interpret what is seen at the entrance more reliably.

2. What the article shows

Fig. 1: The image sequence above is taken from a video shot with a Phantom V2511 camera, here operating at 25 000 frames per second*. It shows the complete motion of a bee in forward flight (frame 8 resumes the motion begun in frame 1). During flight, in one complete wingbeat, the bee moves the wings from rear to front and downwards, with the wings rotated forward. It then rotates them backwards in order to bring them back rearwards and upwards. Note (1) that the wing motion is back-and-forth and not up-and-down, (2) that the wings are flexible and (3) that the wings are capable of rotation and torsion. (© J. Kievits – Video “Honey bees in ultra slow motion” (Michiganshooter))

Question. Janine Kievits’s article asks a deceptively simple question: how can a bee fly with such speed, precision and ease? The answer draws on several levels of explanation: the evolution of insect flight, the structure of the cuticle, the shape and flexibility of the wings, the thoracic musculature, the wing joints, and the bee’s visual capacities.

Method. The article is not a new experimental study but a review and outreach piece. Kievits draws on work in anatomy, biomechanics, aerodynamics and neurobiology, and illustrates wing motion with a sequence of images from a high-speed video.

Results. The article first shows that wing motion is more complex than a simple vertical beat. In forward flight, the bee moves its wings from rear to front and back again, with rotation, torsion and bending. The wings are therefore at once light, supple, and capable of bearing strong mechanical loads.

Kievits then recalls that the wings are outgrowths of the cuticle. They are formed of cuticular lamellae, traversed by veins, and equipped with sensory structures. In the bee, forewings and hindwings are coupled by hamuli, small hooks borne on the hindwing that lock into a groove on the forewing. This coupling allows both wings to function together as a coherent flight surface.

The article also explains that insect flight aerodynamics is not understood like that of an aeroplane or a bird. At the scale of a bee, air behaves differently: flight relies on rapid movements, wing rotations and the formation of vortices that contribute to lift.

The power for flight comes mainly from the indirect muscles housed in the thorax. These muscles do not pull directly on the wings: they deform the thorax, and that deformation drives wing motion. Their asynchronous operation enables very rapid cycles. Small steering muscles, connected to the articular pieces at the wing base, then orient the motion finely and explain flight precision.

Finally, Kievits devotes a substantial part of the article to vision. The bee does not see as we do: its vision is less precise at a distance but very motion-sensitive. It uses optic flow — the apparent motion of the landscape across the retina — to stabilise its flight, to slow down in a narrow passage, to avoid obstacles and to land.

The article broadens the perspective by recalling that insect flight is an ancient and considerable evolutionary success, and that the origin of wings is still debated on the basis of morphological and genomic data. For an apicultural article, this section mainly highlights the evolutionary depth of the phenomenon, without leading directly to a practical implication.

Interpretation. The central message of the article is that bee flight emerges from an integrated system. Wings, cuticle, hamuli, thorax, muscles and vision do not function separately: they form a coherent whole, suited to an insect that must forage, avoid obstacles, return to the hive and land with precision.

3. Critical appraisal

This chapter clarifies the article’s actual scope and the limits of its translation into apiary practice.

Strengths of the article. The main strength of the text is its integrative approach. It connects fields that are often presented separately: wing anatomy, properties of the cuticle, hamuli, flight muscles, wing joints, compound vision and optic flow. This articulation makes the article useful for understanding why a bee can accelerate, slow, change direction, avoid obstacles and land precisely.

The article is also of interest to the beekeeper because it gives meaning to everyday observations: the speed of flight at the entrance, hesitations on landing, orientation flights, the importance of the immediate visual environment around the hive, and wing wear in old foragers.

Limits. The article is not a field study on apiary management. It does not test the effect of a site, a hive colour, an obstacle, a hedge, an entrance orientation or colony density on colony health or productivity.

Another limit lies in the nature of the work it draws on. Much of what is known about flight comes from high-speed videos, flight tunnels, mechanical models, simulations or simplified experimental setups. These methods are powerful for understanding mechanisms, but they do not replace observations in real apiaries with variable weather, terrain, forage conditions, colony density, bee races and different beekeeping practices.

Possible biases and confounders. At the apiary, unusual flight may have many causes: wind, temperature, nectar flow, nectar or pollen load, young bee age, orientation flights, robbing, drifting, predation, bee poisoning, viral disease, varroa infestation, or general weakening of the colony. The article helps to understand the mechanics of flight but does not provide a method for health diagnosis.

What cannot be concluded. One cannot derive from this article a strong rule on the ideal hive colour, the optimal distance between colonies, the exact orientation of entrances, or the ideal layout of a Swiss apiary. These questions belong to specific studies on orientation, drifting, visual landmarks, colony density and local conditions.

Transposition to a Swiss or European apiary. The basic mechanisms described in Apis mellifera are relevant to Swiss and European apiaries. The practical implications, however, depend strongly on context: altitude, exposure, prevailing wind, hedges, terrain, proximity to other apiaries, varroa pressure, forage resources, and local risks. The text should therefore be read as an aid to observation, not as a manual for designing the apiary.

4. What related studies show

Related studies confirm several mechanisms described by Kievits and add precisions on biomechanics, orientation and drifting.

Direct replication and biomechanical support. Altshuler et al. (2005) and Vance et al. (2014) directly support the view that bee flight relies on rapid, low-amplitude wingbeats heavily dependent on wing rotation. In hovering flight under experimental conditions, reported values lie around 227–230 Hz, with an amplitude of about 87–90°. When mechanical demand increases — for example in ascent or in experimentally rarefied air — the bee mainly increases beat amplitude rather than beat frequency.

Mechanistic support concerning the thorax. The functioning of the indirect flight muscles cannot be reduced to a simple repeated muscle contraction. Kievits presents the thorax as a resonant system whose elasticity contributes to flight efficiency. Jankauski (2020) refines this point: the bee thorax does have a measurable mechanical response, close to a spring–mass system, but the natural frequency that is measured does not simply coincide with the actual wingbeat frequency. The idea of resonance therefore remains useful, but it should be understood as a mechanism of mechanical efficiency, not as a sole explanation of flight frequency.

Mechanistic support concerning wing coupling. Michels et al. (2020) and Toofani et al. (2020) reinforce the section on hamuli. They show that the coupling between forewing and hindwing combines rigid hooks, more flexible bases and resilin-rich zones. This arrangement provides locking, flexibility, stress damping and durability across very many wingbeat cycles at once.

Methodological complement on optic flow. Work on the visual control of flight strongly confirms the role of optic flow. Baird et al. (2005) show that bees adjust their speed from the visual flow. Barron and Srinivasan (2006) show that they compensate for headwind in order to maintain a consistent ground speed. Baird et al. (2013) describe a landing strategy based on the rate of image expansion. Singh et al. (2024) show that obstacle avoidance also relies on dynamic visual cues that first trigger slowing and then a lateral deviation.

Theoretical context useful for the apiary. Studies on orientation show that bees learn visual landmarks around the hive and in the landscape. Degen et al. (2016) show that orientation flights allow young foragers to learn landscape features. Dynes et al. (2019), in a trial conducted in Georgia with 48 colonies, compared apiaries that were tightly aligned, visually uniform and spaced about 1 m apart with apiaries that were more widely spaced, arranged in a circle, and visually differentiated. Colonies in the more widely spaced and more distinctive arrangement showed less drifting and better indicators of production and overwintering. This study is useful for thinking about drifting, but it does not allow the effect of colour, distance, height or arrangement to be isolated, and its transposition to a small or medium-sized Swiss apiary should remain cautious.

Limits for practical interpretation. Two extensions would be especially useful for the beekeeper: the effects of viral diseases — in particular Deformed Wing Virus (DWV) — on flight ability, and the sublethal effects of certain pesticides on orientation or return to the hive. These topics are not, however, documented by the complementary results provided for this synthesis. They are therefore not used here as bibliographic support for chapter 4.

5. What to take away for the apiary?

At the apiary, the main contribution is to sharpen observation and practical layout, without turning flight biomechanics into hasty recipes.

• Observe flight, but do not diagnose too quickly. Unusual flight behaviour at the entrance deserves attention, because flight depends simultaneously on wings, muscles, vision and the bee’s general condition. On its own, however, it is not enough to make a diagnosis. It must be set against weather, nectar flow, risk of robbing, the colony’s state, varroa infestation, and other visible signs.
• Keep a clear flight path in front of the hives. Bees rely heavily on visual information during take-off, approach, landing and obstacle avoidance. In practice, it is useful to avoid immediate, moving or overly close obstacles near the entrance, without seeking to remove all vegetation around the apiary.
• Maintain visual landmarks around the apiary. Studies on orientation flights show that young foragers learn landmarks around the hive and in the landscape. Stable landmarks, recognisable entrances and a nearby environment that does not change abruptly can therefore help bees find their colony again, especially after a change in the apiary.
• Use colours and patterns as cues, without making this an absolute rule. Bees do not perceive colours as we do and respond strongly to contrasts, movement and stable visual structures. In dense or very uniform apiaries, it can be useful to differentiate entrances not only by colour but also by shapes, simple patterns or clearly distinct landmarks. This can support orientation and limit drifting, but it replaces neither a good apiary layout, nor sufficient spacing where space allows, nor varroa monitoring.
• Distinguish normal wear from a health sign. Slightly worn wings in old foragers are common and are not, on their own, sufficient to conclude a disease is present. By contrast, deformed wings, crawling, trembling or flightless bees are warning signs and should lead to a broader health assessment.

Read the original article

Kievits, J. (2024). “En vol”. La Santé de l’Abeille, no. 319, January–February 2024, p. 39–54. 

Further reading on ApiSavoir

• How do bees see?
• Practical Guide: 4.8.1 Entrance observation
• Deformed wing disease
• Drifting and re-infestation: why apiary layout matters against varroa
• Practical Guide: 4.9 Choice of apiary site
• Dancing has to be learned

References

Altshuler, D. L., Dickson, W. B., Vance, J. T., Roberts, S. P., & Dickinson, M. H. (2005). Short-amplitude high-frequency wing strokes determine the aerodynamics of honeybee flight. Proceedings of the National Academy of Sciences of the United States of America, 102(50), 18213–18218. https://doi.org/10.1073/pnas.0506590102

Baird, E., Srinivasan, M. V., Zhang, S., & Cowling, A. (2005). Visual control of flight speed in honeybees. Journal of Experimental Biology, 208, 3895–3905. https://doi.org/10.1242/jeb.01818

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, 110, 18686–18691. https://doi.org/10.1073/pnas.1314311110

Barron, A. B., & Srinivasan, M. V. (2006). Visual regulation of ground speed and headwind compensation in freely flying honey bees (Apis mellifera L.). Journal of Experimental Biology, 209(5), 978–984. https://doi.org/10.1242/jeb.02085

Degen, J., Kirbach, A., Reiter, L., Lehmann, K., Norton, P., Storms, M., Koblofsky, M., Winter, S., Georgieva, P., Nguyen, H., Chamkhi, H., Meyer, H., Singh, P., Manz, G., Greggers, U., & Menzel, R. (2016). Honeybees learn landscape features during exploratory orientation flights. Current Biology, 26(20), 2800–2804. https://doi.org/10.1016/j.cub.2016.08.013

Dynes, T. L., Berry, J. A., Delaplane, K. S., Brosi, B. J., & De Roode, J. C. (2019). Reduced density and visually complex apiaries reduce parasite load and promote honey production and overwintering survival in honey bees. PLOS ONE, 14, e0216286. https://doi.org/10.1371/journal.pone.0216286

Jankauski, M. (2020). Measuring the frequency response of the honeybee thorax. Bioinspiration & Biomimetics, 15. https://doi.org/10.1088/1748-3190/ab835b

Kievits, J. (2024). “En vol”. La Santé de l’Abeille, no. 319, 39–54.

Michels, J., Appel, E., & Gorb, S. N. (2020). Coupling wings with movable hooks — resilin in the wing-interlocking structures of honeybees. Arthropod Structure & Development, 60, 101008. https://doi.org/10.1016/j.asd.2020.101008

Singh, S., Garratt, M., Srinivasan, M. V., & Ravi, S. (2024). Analysis of collision avoidance in honeybee flight. Journal of the Royal Society Interface, 21. https://doi.org/10.1098/rsif.2023.0601

Srinivasan, M. V. (2011). Honeybees as a model for the study of visually guided flight, navigation, and biologically inspired robotics. Physiological Reviews, 91(2), 413–460. https://doi.org/10.1152/physrev.00005.2010

Toofani, A., Eraghi, S., Khorsandi, M., Khaheshi, A., Darvizeh, A., Gorb, S. N., & Rajabi, H. (2020). Biomechanical strategies underlying the durability of a wing-to-wing coupling mechanism. Acta Biomaterialia, 110, 142–151. https://doi.org/10.1016/j.actbio.2020.04.036

Vance, J. T., Altshuler, D. L., Dickson, W. B., Dickinson, M. H., & Roberts, S. P. (2014). Hovering flight in the honeybee Apis mellifera: Kinematic mechanisms for varying aerodynamic forces. Physiological and Biochemical Zoology, 87, 870–881. https://doi.org/10.1086/678955