Indeed. So why the need to invoke intelligent design when there is no reason to do so ? After all nature itself is quite capable to generate what we see and we have yet to see 'intelligent design'. It cannot be observed, it cannot be predicted but hey, it only requires a little bit of faith to invoke the tooth fairy explanation. It makes for interesting stories but poor science.
After all let's assume there is 'intelligent design'. Who is the designer ? Another species from outside our worlds ? The Christian God ? Or any of the many other Gods ? THey all make equally well candidates of this 'intelligent designer', or should that be equally poor ?