The visual ecology of bees - Tales of diverse eyes and behaviours

• Main Author: Tichit, Pierre
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: MediaTryck Lund 2021
• Subjects: Zoology; Animal behaviour; Arthropods; Bumblebees; Compound Eyes; Crystalline cones; Flight control; Image analysis; Landing; Sensory ecology; Stingless bees; Vision; X-ray microtomography; Greenland; Thumb; Tundra
• Online Access: https://lup.lub.lu.se/record/ab85ee5d-ef1d-4068-9b51-ce01cd8f449d; https://portal.research.lu.se/files/96141025/e_spik_ex_Tichit.pdf

The buzzing flight of bees is a popular summer hit. Yet, outside of a few familiar species of honeybees and bumblebees, these fantastic little creatures are still mostly unknown. With about twenty-five thousand species, bees are a very diverse group. They can be found in drastically different habitats. For example, some kinds of bumblebees endure the freezing temperatures and windswept tundra of Greenland, while others only thrive in the heat and humidity of the Amazonian forest. Some bees live in huge colonies with tens of thousands of members, while others live solitary lives. Some are narrower than a sesame seed, while others can reach the size of a human thumb. Despite these differences, bees all have in common the urge to visit flowers where they find their food. This habit makes them very important for the pollination of plants across the world. To go about their laborious life, bees make extensive use of their vision. They possess two types of eyes – ocelli and compound eyes – that they use to control their flight, find their way through the world, discover flowers and spot possible mates. To understand how bees interact with the environment, we thus need to explore the diversity of their eyes and of how they use them.The first chapter of my thesis is about landing, which is a fundamental behaviour in flying insects. However, in bees it is poorly known whether different species land in different ways. During an expedition to Brazil, I came across a species of bee with the most peculiar landing style. Rather than slowing down to land, as most animals do, these bees accelerate just before touchdown on the entrance to their hive. Why do these bees speed up when they land? Using a computer simulation, I found that this weird strategy may help the bees to avoid mid-air collisions with nestmates and reduce bee ‘traffic jams’ in front of the hive. In turn, this would make food collection more efficient for the colony and it would be easier for hive members to defend against intruders. With this chapter, I showed ...