I know autism is typically shown as a child but can Autism also first show its signs in adulthood?

It may sound stupid, but are there two types of autism, one that develops in late teens/early adulthood or is just childhood?

Autism is a complex developmental disability that typically appears during the first three years of life and affects a person’s ability to communicate and interact with others. Autism is defined by a certain set of behaviors and is a "spectrum disorder" that affects individuals differently and to varying degrees. There is no known single cause for autism, but increased awareness and funding can help families todayYou can educate yourself more by clicking on this siteAUTISM SOCIETY OF AMERICAhttp://www.autism-society.org/...

If it is environmental as many believe, yes it can present later in life. But, most often the toxins are introduced to those sensitive to them in early childhood. There are not really two types of autism, there are millions, one for every affected person. I've yet to see two people who present in the same way with a diagnosis autism. BTW - It doesn't sound stupid, but a legitimate question. Here is a site where lots of people know about autism first hand, not just from psych books. http://health.groups.yahoo.com/group/Autism-Mercury/

Bruno Bettelheim saw typical autistic symptoms appear in adults who were truamatized in Nazi death camps. It was this observation that led him to believe infants develop autism from trauma during vulnerable periods of development--at birth or at age two. Things like cesarean birth or premature birth or severe neglect could lead to a predisposition to autism. Trauma wasn't the only things that could cause autism though. It could also be precociousness at birth or extrodinary physical beauty or talent in infancy resulting in excessive self-love, which in turn made it attractive to withdraw into oneself as an easy defense against anxiety. Modern psychiatrists have decided to call the autistic symptoms displayed by adults who have suffered trauma "Post Traumatic Stress Disorder."Such classifications are purely arbitrary, though, and are often influenced by political considerations. For instance; doctors do not wish to equate PTSD with infantile autism for fear of causing mothers to have guilt trips.