Insect societies have evolved communication systems of remarkable complexity*. Highly social bees (honey bees and stingless bees) use sophisticated methods to exploit resources such as pollen, nectar, water, resin and nest sites. Social bees can recruit, increase the number of nestmates at a particular location or increase the number of nestmates searching for a particular resource at non-specific locations (Nieh and Roubik 1995; Nieh, Tautz et al. 2000; Nieh 2004; Sánchez, Nieh et al. 2008; Kuhn-Neto, Contrera et al. 2009; Sánchez, Nieh et al. 2009).

*Karl von Frisch (1923) "Uber die'Sprache'der Bienen." Zoologische Jahrbucher Abteilung fur Allgemeine Zoologie und Physiologie der Tiere 40 (1923): 1-186. This landmark paper, after over 95 years, is now in the public domain and deserves to be appreciated in its original. Please feel free to download and share!

Research in the Nieh lab examines the mechanisms that allow highly social bees to communicate resource location and seeks to understand how these communication systems have evolved (Nieh 2009; Ramírez, Nieh et al. 2010).

Asian hornets like Vespa velutina are, like the bees we study, highly social, and have their own sophisticated communication. Such signaling is inherently interestingly and may also offer insights into ways to control these invasive insects. In the video below, you can hear the scraping sounds created by larval hornets. This may be a hunger signal and is part of our research into hornet communication.

Predators such as Asian hornets have likely engaged in an evolutionary arms race with prey such Asian honey bees. The hornet are large and have exceptionally thick armor that bee stings penetrate with difficulty. Honey bees have evolved heat-balling, which takes advantage of their ability to recruit large number of nest defenders to swarm around the hornet and kill it with heat and elevated carbon dioxide levels. However, this is a costly defense, and, as such, one expects the evolution of warning signals. In fact, Asian bee species have evolved a fascinating wing flicking display, the "I See You" (ISY) signal that warns the hornet it has been detected. This type of warning is part of broad category of alarm signals found in many types of animals and part of what we studying in China. Why is the ISY signal effective? Is it truly an honest signal? Under certain circumstances, can "bluffing" be a useful strategy for animals like bees?

Honey bees have a wide variety of vibratory signals, such as the shaking signal. The shaking signal serves a variety of functions related to reallocating colony labor. For example, bees that receive the shaking signal have an increased likelihood of moving down to the dance floor where they can engage in foraging-related tasks.

Honey bees also use functionally referential communication, the transfer of environmental information into coded signals understood by a conspecific receiver. Such a system may be a sophisticated form of animal communication because of the cognitive complexities presumably involved in transforming sensory information into coded communication signals.

For example, the video below showcases some of the research of Tim Landgraf, a collaborator. This video shows some of Dr. Landgraf's fascinating research into developing a robot waggle dancer, a bee that can communicate food location to bees by using their own communication system. To copy the natural waggle dance with a robot, Dr. Landgraf developed a series of analysis tools that we will be sharing to analyze other honey bee communication signals. Our goal is to understand what makes a bee signaling behavior attractive to signal receivers. To learn more about Dr. Landgraf's research and see a higher quality video of his robot bees, please see this Deutsche Welle website.

However, the question of how functionally referential communication has evolved in bees and whether it exists only in honey bees, within the bees, remains relatively unexplored. Part of our research focuses on the possibility that some species of stingless bees in the genus Melipona may referentially encode the location of a food source (Nieh and Roubik 1998; Nieh, Contrera et al. 2003).

This video shows a stingless bee (Melipona panamica) communicating inside the nest to recruit nestmates to a rich sugar solution.

Honey bees (Sadler and Nieh 2011), stingless bees (Nieh and Sánchez 2005; Contrera and Nieh 2007), bumble bees (Nieh, Leon et al. 2006; Mapalad, Leu et al. 2008), and wasps (Eckles, Wilson et al. 2008) can regulate their body temperature (specifically the temperature of the thorax) according to resource quality. In these flying insects, elevated thoracic temperatures are correlated with increased flight muscle power. Thus, foragers may be able to fly back and collect rewarding resources more rapidly if their flight muscles are warmer. In addition, such elevated thorax temperatures may be sensed by bees inside the nest and provide information (Hammer, Hata et al. 2009).

In some cases, the need to maintain thoracic muscles at a specific temperature range or warm flight muscles to achieve sufficient power for flight may provide a clue to how sound and vibrational foraging signals evolved. For example, the buzzing sounds produced by Melipona panamica foragers just prior to takeoff from a food source increase under cold ambient conditions and are similar to buzzing sounds produced during recruitment, just before the bee flies from the nest to the resource (Contrera and Nieh 2007).

Finally, chemical communication plays a key role in the foraging of honey bees, stingless bees (Nieh, Contrera et al. 2004; Contrera and Nieh 2007; Sánchez, Nieh et al. 2008; Lichtenberg, Hrncir et al. 2009; Nieh 2009; Sánchez, Nieh et al. 2009), and bumble bees (Renner and Nieh 2008). Our lab is currently investigating how chemical cues and signals of predation affect bee foraging (Nieh 2010).

It turns out that stingless bees can produce sounds while collecting a nectar-type reward. In the video below, we see the stingless bee, Melipona panamica collecting a rich sucrose solution from an artificial feeder while a microphone (white tube) records the different sounds made by the forager. It turns out that bees produce more of these sounds when the temperature decreases. The sounds are produced by bees buzzing their flight muscles, which need to achieve a certain minimum temperature for efficient flight. Thus, the sounds may be a byproduct of this muscle warming.

Learn more about the study of Behavioral Ecology at UCSD.