Answer:
family
Step-by-step explanation:
According to Call of the Wolf by Jack London, the story is narrated in the third person anonymous narrative and talks about a dog Buck who lived a relatively comfortable life on Judge Millar's estate but is eventually drafted to become part of a team of dogs that pulls sleds.
Buck regains his primal instinct of hunting and scavenging as he is thrust into the wild by his numerous masters.
Therefore, whenever Buck's ancestors are mentioned, it evokes the concept of family.