piles known as moraines I’m pretty sure
The correct answer is birth.
At birth, females infants on an average appear to have a more developed central nervous systems compared to males. This is apparent because female infants shower higher levels of responsiveness to stimuli such as sounds, touch and faces. Additionally, female infants typically acquire linguistic abilities and vocalize earlier than male infants.
A box full of feathers and the same size box full of rocks. They occupy the same volume but have a different mass.
(A 1 meter by 1 meter by 1 meter cube box full of feathers.
A 1 meter by 1 meter by 1 meter cube box full of rocks.)