When people use the words "natural" these days, they are usually using it to express distaste for things they consider unnatural. This doesn't mean it is preferable. It is natural for a lion to bite a human, but it is not preferable! So, it doesn't really mean anything at all.
If something is "natural" it implies that is what the majority of people prefer. It doesn't mean something "natural" is more right than something else. It is "traditional" for a family to have a parent of one sex and a parent of the opposite sex. That doesn't mean it is the "only" choice. If a homosexual couple wants to adopt, they have the right to do so if they follow the same guidelines of a heterosexual couple.
The question is not if "natural" is right, but if it's implied that it's preferable. I believe the majority of the world prefer to be "normal" and to fit in. For obvious reasons of course: there is being bullied for being different, or outcast. If you're just normal, then you're not extreme one way or another and therefore are not the center of drama, or potential humiliation. To say you have a normal child means you have a preferable child. It is quite uncommon to hear parents say "I hope my child is born unnatural; with 13 toes and blind." You hear parents say "I just want my child to be healthy." Healthy is natural.
No. First off who is to say that gay and lesbians are not natural people. Just because something does not fit into to the majority of society, it does not make it unnatural by any measure. I believe that if a person or couple meet all the criteria for adoption, regardless of their sexual orientation, they should be able to do so.
Natural is a very biased term. We throw it around a lot, forgetting that a lot of our more base impulses such as those toward greed and bigotry are natural to the human ego. So a gay couple might not seem natural on one level but on another is very much a part of the natural world and any person or person who has love to give should be able to adopt.
I think gay adoption should be allowed. It makes no sense to tell a gay that they can not adopt when there is so many children still in shelters and do not have homes and we keep overpopulating the earth. Let people have children, it doesn't matter their sexual preference.
If we are to deny gay couples the right to adopt children, with the reasoning that it's "unnatural" we should also deny single women or a couple unable to conceive that same right. The ability to adopt children should have nothing to do with the ideas of what is "natural." All children deserve to grow up in a house full of love, where they are wanted by those that provide for them. Not all children who live with their biological parents are afforded that, despite how "natural" that family unit is accepted to be.