Aspecies of rose (plants) lacks thorns. how would biologists explain how a species of rose lacking thorns evolved from an ancestral rose species with thorns?

I think I can answer this fully but I'm not sure what the conditions of the rose you are given is. Roses are angiosperms, meaning that they can produce fruit to cover their seeds to repopulate. When you think about what might eat the fruit, you may think about animals. When the animals eat the fruit the seeds are then pooped out and the fecal matter acts as a fertilizer for the seeds. Now, lets say that a long time ago there were many roses which included roses with and without thorns. When the animals went to eat the fruit off of the roses with thorns, the thorns ight have hurt the animal, and the animal would then avoid the roses with thorns because they knew it would cause pain. Instead, they mainly fed on the fruits from the roses without the thorns because it wouldn't have thorns that might hurt them. Over time, animals avoided the roses with thorns, and so the seeds were never spread, and the roses with thorns couldn't repopulate and died. Over time, the roses gene pool narrowed down to only the roses without thorns because the animals would only eat fruit from the roses without thorns, thus spreading the seeds and helping them repopulate, and that is why today they are roses without thorns.