In the beginning of the quarter, I introduced the topic of communication and emphasized the beauty of its intricacies. On an everyday basis we may take communication for granted and brush it off with little notice; we fail to acknowledge and appreciate how incredibly complex it is. When talking to a friend or calling out to a loved one, we do not think about the years and years of evolution that have molded our communication systems into the efficient system it is today. The environment is always changing such that the world of our ancestors was much different than ours at present day. We face and are presented with many different factors, and Endler reminds us that it is these “factors that affect signals [. . .] constrain or bias the direction of evolution of signals and signaling systems” (Endler, 1993). As I mentioned in my first post of the quarter, the phylogenetic history of a species works hand in hand with the geological time a clade spends in the signaling environment to produce a specific type of signaling design, thus evolving to increase the efficacy of transmission of the message between emitter and receiver.
The first example I discussed was that of the honeybee. Their waggle dance proved useful during their careers as foragers such that they could use location information acquired from the dance to find the indicated food source which in turn contributed to the foraging success of a honey bee colony” (Biesmeijer & Seeley, 2005). We saw, however, that not all bees used the used the waggle dance in the same manner. Honeybees were more like to use information obtained through a waggle dance if they failed to find food on their previous trip or if they were a novice, foraging for the first time. Therefore, the waggle dance was not just a simple communication system utilized by all. Instead, its usefulness was determined by the characteristics and factors revolving around the recipient. From Biesmeijer and Seeley’s article, we saw how the value of certain communication systems can differ depending on the situation. We cannot state a communication system’s benefit in simple terms.
We then waltzed our way into the discussion of another type of honeybee dance, the shaking dance. Although the purpose of this dance was unknown, Gahl found that of the 44.8% of the bees that danced atop another, 96% of the bees danced on a honeybee that was younger than themselves. The majority of the shakers were 9-19 days old and the bees shaken were mostly 2 days old, showing some sort of discrimination by age. From this, Gahl illustrated how communication can have these types of discriminations between the recipient and producer. Communication is not always general across a whole species. Instead, the recipient and producer often times hold certain relationships, which affect the type of communication. We see this in humans as well. For most cultures, we speak differently towards our elders in comparison to those the same level as us or even younger than us. We communicate with different levels of respect depending on if we are talking to our boss, our family, or an aquaintance. Communication is not straightforward but instead depends on certain discriminations.
Then, from honeybees we transitioned to monkeys and discussed the systematic use of distinguishing signals that represented a distinction of objects and a sorting of objects into groups. We focused specifically on predator classification of vervet monkeys through their acoustically different alarm calls to at three different predators: leopards, martial eagles, and pythons (Seyfarth et al. 1980). Upon hearing the different calls that indicated a specific type of predator, the monkeys responded in a specific and respective manner that “seemed to represent adaptive strategies for coping with the hunting behavior of the predators involved” (Seyfarth et al. 1980). Leopard alarms caused monkeys to run up into the trees, eagle alarms caused monkeys to run into a dense bush for cover, and snake alarms caused monkeys to look down towards the ground for their predator. They responded “as though each type of alarm call designated different external objects or events” (Seyfarth et al. 1980). Therefore, this systematic use of signals means that the animals must understand contextual communication cues. An alarm signal can elicit general behavior to remove oneself from danger. However, vervet monkeys show much more complex behavior; they have to know how exactly to remove themselves from danger by knowing what type of danger they are in. Through this article, the importance that both the producer and the recipient must share similar knowledge was illustrated, otherwise this type of communication would fail and would not be as beneficial to the species. The results revolving around younger vervets further supported this point. They did not encompass as much knowledge as their adult counterparts; there was a difference in the amount of information and experience between recipient and caller. Therefore, they made false alarms to twigs and harmless shadows, proving to be inefficient at such calls.
We then went from identifying types of predators to identifying oneself in the bottlenose dolphins. The distinctive calls, unique on the level of the individual, was shown to be encoded by the pattern of frequency modulation that gave a spectrographic contour its distinctive shape (Janik et al., 2006). Janik et al. showed that such calls did not rely on specific voice features on the individual, but instead depended on the shape of the call itself. This revealed the power of communication stripped down to its basic form. Just the frequency pattern alone can achieve, at least in some species like the bottlenose dolphins, very efficient communication means.
The last two articles we discussed looked at communication in King Penguins and the search for their respective mates. The first of the two commented on the efficacy of their communication. An astounding 70.17% of the land partners were able to discriminate the very first call of their returning mate, and the average distance between the two was found to be 8.3 meters. This proved to be a very impressive feat taking into consideration how massive and extremely dense the colonies were. The second article took it a step even further, and their results showed that penguins actually alter their communication mean depending on the weather. With windier conditions, penguins increase their call duration and number of syllables, even taking into account the direction of the wind (upwind or downwind). Lengagne et al. referred to this as a “redundancy process” where the probability of successful communication may be increased by repeating the same information many times. Therefore, we saw how communication is not a simple and straightforward output-input system. It, along with almost all types of communication, is extremely dynamic and sensitive to many variables that affect the modality, efficiency, and characteristics of communication.
From all these articles, we can now appreciate and admire specific examples reflecting the beauty of communication. Animal studies allow us to delve into our own world and perhaps better understand how complex human communication is as well. There are many types of forms, strategies and modes that have been tweaked and are still being perfected for the present environment. One type of communication might prove to be beneficial to one species or in one context but not so in another. There is a unique interplay between many factors, but overall, like the common saying goes, communication is key!
Endler, A. J. (1993). The evolution and design of animal signaling systems. Biological Sciences, 340(1292), 215-225.
Biesmeijer, J. C. & Seeley, T. D. (2005) The use of waggle dance information by honeybees throughout their foraging careers. Behavioral Ecology and Sociobiology, 59(1), 133-142.
Gahl, R. A. (1975) The shaking dance of honey bee workers: evidence for age discrimination. Animal Behavior, 23(1), 230-232.
Seyfarth, R., Cheney, D., & Marler, P. (1980) Monkey responses to three different alarm calls: evidence of predator classification and semantic communication. Science, 210(14), 801-803.
Janik, V., Sayigh, L., & Wells, R. (2006) Signature whistle shape conveys identity information to bottlenose dolphins. Proceedings of the National Academy of Sciences, 103(21), 8293-8297.
Lengagne, T., Jouventin, P., & Aubin, T. (1999). Finding one’s mate in a king penguin colony: efficiency of acoustic communication. Behaviour, 833-846.
Lengagne, T., Aubin, T., Lauga, J., & Jouventin, P. (1999). How do king penguins (Aptenodytes patagonicus apply the mathematical theory of information to communicate in windy conditions?. Proceedings of the Royal Society of London. Series B: Biological Sciences, 266(1429), 1623-1628.