Complex sentence: Acorn woodpeckers ("Melanerpes formicivorus") are known to form communal roosts during the winter months, sharing their body heat and thus decreasing the thermoregulatory demands on all individuals within the roost.
Split into simpler sentences: Acorn woodpeckers ("Melanerpes formicivorus") are known to form communal roosts during the winter months. Within these roosts woodpeckers share their body heat with each other and therefore decrease the thermoregulatory demands on all individuals within the roost.