All over the world, you can see animals wrestling
with the emotions a newborn brings,
but it's clearest in primates.
In Madagascar, ring-tailed lemurs have to stay together to survive,
particularly in a drought.
One of the babies is too weak to hold on.
Lemurs can't easily carry their young,
so the mother faces an appalling dilemma.
If she's separated from the others for too long,
they could attack her as an outsider.
She has to choose between her baby and herself.
The mother moves to follow the troop,
but she returns five times.
Her mind must be struggling back and forth.
Many scientists believe she feels emotion
and is thinking about her feelings.
It's called affective consciousness.
It's now thought likely all mammals
are aware of their instinctive feelings.
It would be hard to be a good mother without it.
As her baby got weaker,
she left for the last time.
We can't know for sure what she was thinking or feeling, but she behaved
as though she'd come to a decision that she found very difficult.
Emotions are just instincts that you can feel,
that you are aware of.
They're the voices of our genes and our past.
But conscious minds can manipulate each other's emotions
right from the start.
A vervet monkey is born.
The baby meets a young cousin.
He may be a new friend, an ally or competition.
It all depends on his mother's social standing.
She is not the only one in her community having a baby.
For the teenage sisters, it's a thrilling time.
They beg any chance to hold the newborns.
The high-ranking females don't beg,
they grab babies and teach them who's boss.
Junior mothers have to be more protective.