Life explained

On the first day, G-d created the dog and said:

'Sit all day by the door of your house and bark at anyone who comes in
or walks past. For this, I will give you a life span of twenty years.'

The dog said: 'That's a long time to be barking. How about only ten
years and I'll give you back the other ten?'

So G-d agreed.

On the second day, G-d created the monkey and said:

'Entertain people, do tricks, and make them laugh. For this, I'll give
you a twenty-year life span.'

The monkey said: 'Monkey tricks for twenty years? That's a pretty long
time to perform. How about I give you back ten like the Dog did?'

And G-d agreed.

On the third day, G-d created the cow and said:

'You must go in to the field with the farmer all day long and suffer
under the sun, have calves and give milk to support the farmer's family
. For this, I will give you a life span of sixty years.'

The cow said: 'That's kind of a tough life you want me to live for sixty
years. How about twenty and I'll give back the other forty?'

And G-d agreed again.

On the fourth day, G-d created man and said:

'Eat, sleep, play, marry and enjoy your life. For this, I'll give you
twenty years.'

But man said: 'Only twenty years? Could you possibly give me my twenty,
the forty the cow gave back, the ten the monkey gave back, and the ten
the dog gave back; that makes eighty, okay?'

'Yes,' said G-d, 'You may have your wish.'

So that is why for our first twenty years we eat, sleep, play and enjoy
ourselves. For the next forty years we slave in the sun to support our
family. For the next ten years we do monkey tricks to entertain the
grandchildren. And for the last ten years we sit on the front porch and
bark at everyone.

Life has now been explained to you.