12 to 24 hours is the life span of a human ovum
Approximately 24 hours.
May flies have the shortest life span on earth. They live for only 24 hours. These creatures are also called one day insects.
Fireflies can live longer than 24 hours. Their life span can reach seven to 14 days. They live long enough to lay eggs and reproduce.
The beavers life span is about 16-24 years in the wild. See Sources and Related Links for more details.
It means 24 hours in god's life indeed.