Group cohesion, affiliation, and being in sync
This month I’ll be focusing on social relationships between dogs, both in this blog post and in the Research Bites webinar. Dogs are social animals. They live in groups – either with other people or with other people and dogs (or other animals). In order for groups to remain stable, there needs to be strong social cohesion between members. This is an important issue for pet dogs as the break down of group cohesion could lead to increased conflict within the group.
One thing that plays an important role in the level of cohesion and stability within a group is affiliation between group members. A recent paper by Charlotte Duranton (2020) investigates one way in which researchers and professionals may be able to measure affiliation between dogs.
The author defines affiliative behaviors as those “that participate in maintaining proximity between individuals” and therefore act to actively promote social cohesion (Engel and Lamprecht, 1997; Gautrais et al. 2007; Duranton and Gaunet, 2016). Behavioral synchronization is closely associated with affiliation. It simply refers to animals doing the same thing at the same time and place as others (Duranton & Gaunet, 2016). According to Duranton, there are three different aspects of behavioral synchronization:
- Temporal (changing activities at the same time)
- Local (being in the same place)
- Activity (doing the same thing at the same time)
It probably comes as no surprise that increased affiliation results in increased behavioral synchronization and vice versa (Cheng and Chartrand, 2003; Lakin et al. 2003; Ross et al. 2008; Sakai et al. 2010). There is also evidence that synchrony can facilitate bonding (Duranton & Gaunet, 2016). In this paper, the author focused on local synchrony by simply observing how much time dogs spent in proximity to familiar versus unfamiliar dogs.
The study was conducted with 36 dogs living in France. The dogs were between 1 and 10 years of age and healthy. All dogs were friendly toward other dogs.
To assess local synchrony, nine groups of four dogs were observed during a 15-minute walk. The walks took place off-leash and each group followed the same path. The groups were walked separately, so no two groups were in the area at the same time. Each group had two dogs from the same household and two dogs unfamiliar to all other dogs in the group. The owners were instructed not to talk to or interact with the dogs.
In each group one of the dogs from the same family was designated as the target dog. The researcher then measured how much time the target dog spent in proximity to the other three dogs in the group (one familiar and two unfamiliar). Specifically, they recorded:
- The time spent within 1 meter of each other dog
- The time spent within a 5-meter radius of each other dog
- Whether the target dog initiated proximity to the other dog (rather than another dog initiating proximity with the target dog)
Observers watched the videos and coded each group based on the measures listed above. The observers were blind to the relationship between dogs. That is, they did not know which dogs knew each other and which did not.
Results and implications
What did they find? The target dog spent significantly more time close to their housemate and in same area as their housemate, as compared to the unfamiliar dogs. The target dogs also initiated more time with their housemate than with the unfamiliar dogs.
These results tell us that time spent in proximity to each other can be used to assess affiliation between dogs. Note that we only have data for relative time spent with other dogs at this point. That is, we can’t say that if dog spends X amount of time on a walk within 5 meters of a 2nd dog that they, therefore, have a close relationship. However, if we put the dogs in a group of other dogs, we can assess the relative degree of affiliation between group members.
I believe this study provides us with a potential new tool for assessing the relationship between group members. Trainers or shelter staff could observe a group of dogs to determine which dogs tend to spend more time in proximity to each other. Dogs that hang out together are likely to have a more affiliative relationship than dogs that spend less time together. The method would be useful for anyone looking at relationships in groups of three or more dogs. For example, shelters and daycare facilities could use it to determine play groups, and dog walkers could use it to divide dogs into different walking groups. It may also be useful for assessing the relationships between three or more dogs within a household. Another possibility is to apply it to evaluate the relationship between household dogs and a foster dog to determine if the foster dog is a good match for that particular group. Many of you may already be doing this. If that’s the case, then it’s nice to have some research data to back up your approach!
There are several limitations that people need to be aware of if using this method, however. The study was done under specific conditions and at this time we don’t know how generalizable the method is. It’s probably most ideal for determining how closely affiliated two (or more) dogs are when placed in a group with unfamiliar dogs. It’s probably not a huge stretch to also use it to assess the relationship in a group of dogs that are all familiar with each other. However, we don’t know if it has any predictive value. For example, if we put three or four dogs together that had never met and dogs 1 and 2 spent more time together, does that indicate that those two dogs will get along better with each other than dogs 3 and 4? We have no evidence on this, so I recommend being very cautious about making such predictions.
It’s also important to remember that this is only one study in only one context. We need more data to draw any strong conclusions. For this reason, if we use time spent in proximity to other dogs as a way to assess affiliation between dogs, it should be used as one of several assessment tools. Other methods may involve taking the individual history of each dog, observations of body language, and matching individuals for qualities such as age and energy level.
There is one more point made by the authors that I think is worth mentioning. Previous research suggests that, in order for observational learning to occur, the behavior of the two individuals must be similar (Kubinyi et al., 2009). Therefore, information on behavioral synchrony between two dogs may be useful for assessing how likely one individual is to learn from the other. Local synchrony could potentially be used as a method for pairing up dogs as “learner” and “mentor” dogs. Duranton suggests that this may make sense in the context of working dogs, or in selecting “helper” dogs for shy or fearful dogs.
Studies like this are critically important to helping canine professionals maximize their ability to effectively work with dogs. It is a huge relief that the dearth of research fro just a few decades ago has given way to a surge in scientific studies that shows no sign of abating anytime soon!
If you are interested in the topic of social relationships between dogs (or just the science of dog behavior in general) and would like to learn more about this topic, please consider joining us for the December 8th Research Bites webinar on post-conflict behavior (reconciliation) in dogs.
Lakin, J.L., Jefferis, V.E., Cheng, C.M. and T.L. Chartrand. 2003. The chameleon effect as social glue: evidence for the evolutionary significance of nonconscious mimicry, J. Nonverb. Behav., 27, pp. 145-162.
Ross, M.D., Zimmermann, E. and S. Menzler, 2008. Rapid facial mimicry in orangutan play, Biol. Lett., 4, pp. 27-30.