The petition even includes a bullet for «Overdoing the alien species,» in which Johnson is called out for apparently not including the right type of extraterrestrial creatures in the film. (cbr.com)
Finally, the most absurd feature of your scenario is the idea that any extraterrestrial creature would just happen to have, first, DNA as it's basic molecule of biological information storage, second, cellular machinery anywhere remotely similar to what animals on Earth have, and finally, would just happen to be close enough genetically to be able to mix their DNA with the DNA of any terrestrial being, and come out with a viable result. (religion.blogs.cnn.com)
But Shane Black «s The Predator will explore the greater details of why these extraterrestrial creatures came to Earth and what exactly they plan to do there. (slashfilm.com)