Based from a huge study that was done with 5,500 respondents who lived in Europe from childhood through late adulthood found that eveningness peaked at ages a. 20 to 21 years.
The study’s results mean that a lot of people are in the stage of peak alertness during the age of 20 to 21 years old. This age is the stage of a person’s life where they are in the young adulthood stage.
Granny thinks about being left behind at the altar.
I believe the answer is Group entitativity
Group entitavity happen only if all members of that group had eliminated all of their individualistic purposes and live solely to serve the group's goal.
One example of a group entitativity would be the Japanese airforce soldiers during world war II, who were glad to conduct 'Kamikaze' (sacrificing their life by colliding their own planes to enemy's base)