I don't think I would like the life of an animal
Near me five little fox cubs were born. I have filmed them many times, from little balls of fluff clustering round their mother for milk up to almost-grown adults who will soon be setting off to find their own territories.
To begin with they could not get out of the garden they were in. Their parents visited them with food regularly for a couple of months and they would play in the sunshine by day, and in the infra-red of the camera by night. They would ignore anyone watching them if they kept still and quiet.
Then one by one the stronger ones learnt how to climb the wall and went off with Mum to the big wide world, coming back with her when she visited the others and playing with their brothers and sisters.
The statistics are that only one in five cubs survives to adulthood. In May there were five. Now there are two. No Mum around now, I dont know whether she is still alive. One (the smallest and weakest) still lives in the birth den, the other returns - - and plays with the last one at home. He brings no food for his little sister, she fends for herself, living mostly on insects or digging for worms.
If either of them see or hear anyone around, they vanish. If there is any food to be found - an insect, a crust put out for the birds, a scrap of anything edible, the first one to it gets it, and eats it fast. They do nothing for each other, and they are wary of every shadow. They certainly worry about things.
Three of their number have vanished, what their end was is uncertain - attacked by an older rival? starved? poisoned? hit by a car and crept off into the undergrowth with a wound to become infected? Their parents have not been seen for weeks either. They could have met a nasty fate too, and not one of the other creatures would or could do anything to help them. They may appear to take illness and death in their stride, but as they don't write their memoirs we can't know that.
The "natural life" without abstract intelligence is not Eden.