What Happens to Early Generation Hybrids?

Would love to have more information on the early hybrid attempts (of any of the cross-breeding races)? I was reading about the unintentional hybrids that were basically destroyed in Atlantis (because they were unable to integrate into their society) and I wonder what do various races do with the early experiments that ... "aren't quite right"? What happens to those beings? Do they have consciousness and souls from inception?