Complex sentence: The initial period during which the "B. dahlbomii" queen is alone and workers are not yet present is called the subsocial phase; the social phase begins when the initial eggs mature into workers that can begin basic foraging activities.
Split into simpler sentences: The initial period during which the "B. dahlbomii" queen is alone without workers is referred to as the subsocial phase. The social phase starts when the initial eggs mature into workers that can begin basic foraging activities.