At the same time, we measured the temperature and wind speed at each of the families’ territories, the size of the birds, the height of the trees, how genetically related different families were to each other, and how far away the different families lived from each other.
This allowed us to determine whether any of these factors could explain why different families build different roosts. For instance, maybe families living in hotter territories build roosts with shorter tubes than in cooler areas, since they would not need much material to insulate them from the cold at night. The similarity in their environment, we reasoned, might explain why weaver families living in close proximity to each other created similar roosts. Or perhaps families that were more closely related to each other (something like cousins and second cousins) would build similar structures?
However, one by one, we excluded all environmental and genetic explanations for the differences in the structures built by different families.
So what happens next?
We plan to continue documenting the architectural styles of different white-browed sparrow weaver families and to record their building behaviour so we can determine how these birds coordinate their behaviour when building together.
Looking in more detail at how the roosts built by these birds across Africa might differ could help us understand to what extent the environment, material availability, individual experiences, and social interactions between individuals affect the building behaviour of these birds. Maybe, like humans, some species of birds have their own architectural traditions passed on across generations through social interactions.
This article by Dr Maria Cristina Tello Ramos was originally published by The Conversation. The views or opinions expressed by individuals do not necessarily reflect those of the University