And that makes social relationships extremely important.
For Josie, however, the challenge was even greater.
If she could not reliably see an approaching animal, she could not always position herself like a healthy lioness.
If she could not clearly see an obstacle, even walking could become dangerous.
If she could not identify prey at a distance, opportunities to hunt would become increasingly limited.
Still, she found ways to survive.
She Was Not Simply Waiting to Be Fed
It would be easy to tell Josie's story as though she became completely dependent on Dawn and Duffy.
But that would oversimplify what observers have reported.
According to Pete Leyland, Josie retained remarkable independence despite her deteriorating eyesight.
Her daughters were willing to share kills with her, but Josie also developed her own strategy for finding food.
One particularly important prey item was the warthog.
Warthogs can disappear into burrows when threatened, making them difficult prey for many predators.
But Josie became adept at digging them out.
Her reduced vision did not necessarily mean that all of her other abilities disappeared.
She could still use her sense of smell, hearing, touch and experience.
Most importantly, she had years of knowledge about her environment.
She knew the landscape.
She knew where prey might be found.
She understood how to survive.
This is one of the most fascinating aspects of aging in wild animals.
Physical decline does not automatically erase experience.
Sometimes an older animal may compensate for reduced physical abilities with knowledge accumulated over years.
Josie's eyesight was failing.
But she was still Josie.
The Power of a Pride
To understand why Josie's story is so moving, it helps to understand what a lion pride actually means.
A pride is not simply a collection of lions traveling together.
It is a social system.
Females often form the stable core of the group. They may hunt together, raise cubs in overlapping social networks and defend their territory.
The Smithsonian's National Zoo describes lions as the world's most social felines and notes that pride members can form strong social bonds. At the same time, lions do not necessarily remain together every moment of the day. Groups may divide into smaller units and reunite later.
That detail is important.
Family does not always mean staying physically side by side every second.
Sometimes it means knowing where the others are.
It means being able to find each other.
It means returning to the group.
And in Josie's case, Dawn and Duffy repeatedly remained part of her world.
A Family That Adapted
There is something deeply human about the way people describe Josie's family.
Her daughters did not need to "rescue" their mother every minute.
They did not need to carry her.
They simply adapted around her.
When they hunted successfully, they could share the opportunity for food.
When they moved through the landscape, they remained nearby.
When Josie struggled to navigate, she had familiar animals around her.
And when she needed to reconnect with them, communication helped.
Lions use vocalizations, including roars and other calls, to maintain contact and coordinate social interactions. The Smithsonian's National Zoo notes that pride members can stay in communication and reunite around important activities such as feeding and territorial defense.
For Josie, those connections may have been particularly valuable.
A nearly blind lioness moving through unfamiliar terrain would face enormous challenges.
But a nearly blind lioness who knew where her daughters were could navigate a very different world.