Table 2.

Description of the structural effects tested in the model.

Structural effects	Description	Graphical representation
Outdegree (density)	Tendency to groom other cows
Reciprocity	Individuals tend to groom cows that previously groomed them
Three-cycle	Individuals tend to reciprocate grooming through triadic closure (generalized reciprocity)
Transitive triplets	Individuals tend to groom cows with whom they share a common contact (triad closure)
Transitive reciprocate triplets	Individuals tend to reciprocate grooming in triads
Indegree popularity	Individuals groomed by a larger number of cows—higher indegree scores—are more attractive to others and will to be groomed by even more cows on the next wave
Outdegree popularity	Individuals that groom many cows—high outdegree scores—are more attractive to others and will be groomed by more cows on the next wave
Outdegree activity	Individuals that groom many cows—high outdegree scores—will groom even more cows on the next wave
Out-outdegree assortativity	Individuals that groom many cows—high outdegree scores—will interact with cows with high outdegree scores

Circles represent nodes, white arrows indicate the transition between two waves. Black arrows illustrate the interaction between nodes and red arrows correspond to new interactions.