What is the impact of evolution of a non human species on us today?

We cannot be sure of that because evolution has never been observed. And since it is a theory, it cannot be proven, even though plenty of evidence exists that it does occur. In addition, since it is so difficult to observe happing in real life, instead of just fossils, its affect on us humans is very hard to measure or even speculate.

One area where there is a hint of what the effect of evolution may be can be observed in bacteria. Though they do not actually evolve into a new species, we can see them change in how they adapt to antibiotics. Some strains of staph, or staphylococcus, have grown so resistant that they have become a danger to us because we cannot use antibiotics to stop them.

At the other end of the scale we have the example of the cockroaches. They are so superbly evolved to survive that they have hardly changed at all in millions of years. It has been said that if we ever have a nuclear war, they may be the only living animals left because they can live in high levels of radiation.

So maybe the answer to what impact evolution has on us today is that there are animals that may actually survive better than can.