Planet with no star. Human society descended from two people trapped there. A female cop and the criminal she was chasing

Question

I read it in about 2015. It seemed to have been written fairly recently.

The story starts some generations after the initial two people were trapped on the planet. About a hundred people are descended from them. One of the original two people was black, the other white.

Sometimes the older people have ceremonies where they show toys their male ancestor made. A car and a house among others. They do not remember what these items are supposed to be.

There is geothermal heat on the planet and some trees produce light.The people eat animals including centipede like ones they do not much enjoy, but they are now short of food. Food is stored overnight in hollow logs.At the beginning of the story the entire population lives close together in a forest.

The protagonist has a younger brother who cannot walk very well. This younger brother domesticated a large hairy animal and rides it. He calls it a horse because of stories about earth.

They go on a long journey including crossing high mountains with the 'horse.' At one point someone finds a huge body of water. He remembers that this is called a C but noone now remembers what the C stood for.

A significant number of the people have a cleft palette. One of the two original people had an aunt with a cleft palette. These people are called bat faced people. The males with cleft palette are unhappy that women do not want to sleep with them as they do not want children with the condition.

Answer 1

Dark Eden by Chris Beckett.

The novel begins about 160 years after two human beings, Angela and Tommy, are stranded on Eden. Their three companions—Mehmet, Michael, and Dixon—have left in a damaged spaceship to get help. Years have passed, and although Angela and Tommy initially held out hope for rescue, they begin to raise children, forming a new society which becomes known as "Family". Frequent and regular incest among their descendants is common, with few children knowing who their father is. Social life centers around powerful rituals: Retelling of story of the stranding, the worship of what few relics remain, myths about Earth, and the need to stay close to Circle—the place where the landing vehicle originally set down, and is supposed to return to and bring them back to Earth. Social norms are strongly adhered to in this matriarchy, and innovation is rare.

The story is told by John Redlantern and he describes the horses:

‘And if you wanted to go somewhere on Earth, you didn’t walk the way we do. Once, in the old old times, Earth people used to go about on the backs of animals called Horses that let people ride them. They were as big as woollybucks, with sharp pointy teeth. But there weren’t enough horses, so in Tommy’s time, people mostly went in cars like this one. You got inside them, like a shelter, and they ran along by themselves on their wheels, as if they were alive.’

Johnny describes one of the people with a cleft lip as batfaces:

I looked into his ugly batface – it was one of the worst batfaces in Family: it looked like he had a whole extra jagged mouth where his nose should be – but I couldn’t think of anything to say. There was no fun in the man. He’d hit you hard for no reason, and then laugh like he’d made a joke.

When Johnny first sees the sea he says:

That couldn’t all be water over there, surely?’ I said to myself. It didn’t seem possible, and yet I remembered stories of such a thing on Earth, a pool that was bigger than all the dry ground put together. The C, it was called for short, but no one in Eden knew any more what that had stood for.