I have a species of ambush predators that are going to be sentient space-farers one day. But to get them on that path I need them to evolve hands, which will lead to tools, and so on.
They come from a world of wide open grasslands, mountainous regions and canyons, no large forests.
The predators themselves are built roughly like tigers, they lack a tail, and instead they have several long flat antenna growing off their heads that they use to entangle prey after jumping onto it in order to bring it down.
What can I introduce to their grassland environment to help them develop dexterous grasping hands?
I can give more information on both the world and predators as needed.