Because they say so and everyone following them surrendered their biological time so they can lead future great great grandchildren generations to believe now isn't eternity next generations forward.
Evolving has 5 waves of great great grandchildren arrived so far evolving specifically one of a kind from last arriving generation gap to the 5th one existed so far. Simple compounding chromosomes to direct link ancestral arrivals left alive next rotation.
Each great great grandchild, 2 parenting next generation, 4 grandparents of next generation, 8 great grandparents to each next generation, 16 great great to each next arrival.
30:1 compression ration of chromosomes to streaming DNA results inhabiting space one of a kind.
why are people so against understanding this simplicity of inhabiting space equally created to adapting as displaced here?
You rather die in character assumed after birth than admit what you have done since going through puberty.