The thing that bugs my brain is how can speciation already of occured, if hybrids cannot reproduce, into another species type.
Speciation occurs when a group of animals becomes separated physically, so that they are only able to breed within their own group. Over time sufficient genetic differences build up within the group that they are no longer able to breed with the other group. At this point speciation is said to have occurred.
So for example if we look at lions and tigers they have a common ancestor, if we were able to go back in time we would see a population of big cats, at some point that population is separated into two groups geographically. At this point the two groups are the same species, each group then continues to breed over successive generations but only within their own group. The environment will cause some individuals to be more successful than others and thus more likely to successfully raise cubs. The traits of those individuals are more likely to be passed onto future generations.
After many, many generations the two groups will have adapted to their environment and will be genetically different from each other to the point where it is unlikely that they can breed even if they werent geographically seperate.
After all the only reason we have ligers is because we put lions and tigers together in a zoo. The only reason we get grolars is because we have forced polar bears into proximity with grizzlys.
So in answer to your question hybrids dont evolve into other species, one species evolves into another new species, and sometimes into more than one new species such as the common ancestor of lions and tigers did.