And as we've seen with Scar, now Simba is the only dominant male.
The pride is unlikely to remain stable for very long.
This time, only one lioness, Bibi, has given birth.
She's keeping well away from the rough-and-tumble of pride life
to protect her two new cubs.
But it will take more than that for Bibi's cubs to grow to maturity.
Their father Simba will have to hold on to power.
And challengers are already arriving.
Not more than 50 meters away, we've got two male lions closing the gap on Simba.
And they look mean. They look really mean.
They have this tight-lipped look when they're hunting,
and that's exactly how the more mature
of these two new males is looking just now.
Let's move around, Dave, and catch up a little bit.
I'm gonna get the camera as well.
Poor guy.
He looks so stable, so secure. Definitely the king of his patch.
And then it all looks so shaky so quickly when the competition moves in.
Oh, watch your back, Simba, watch your back.
There's no more than just a few meters between them now.
Here we go.
This is it. Go, Simba, run boy, run.
For the time being, none of the lions is really prepared to risk
the full-on violence of a fight between adult males.
It can take months for a takeover to succeed,
but they're already sizing each other up.
Simba has age and experience on his side,
but these young challengers look supremely confident.
Roaring in another lion's territory is the ultimate act of provocation.
Simba wisely retreats from the skirmish and re-marks his territory.
But the two new males stay in the area,
and Bibi is about to walk straight into danger.
Bibi has seen all this before.
Her own father Scar took over the pride
only to be ousted three years later by Simba.
Now it's Simba's own cubs that are at risk from these outsiders.
This looks like another takeover in the making,
but it may not be. Simba is alone, but he's in pretty good shape,
and he won't give up his pride without a fight.
Yet at the same time, eight years experience in the Maasai Mara
has taught us that these aggressive outsiders
might make perfect fathers for a new generation of Marsh Pride lions.