It has long been presumed that there is a common cause at the genetic, cognitive, and neural levels for autism's characteristic triad of symptoms. However, there is increasing suspicion that autism is instead a complex disorder whose core aspects have distinct causes that often co-occur.
1 Transition metals are kinds of metals that have electrons in d or f orbitals. 2  Transition metals are in columns 3-12 of the periodic table and in the lanthanide and actinide series.  Most transition metals are lustrous, silvery, hard, and good conductors; however, properties may vary greatly.
Â· just now. 1  Transition metals is the largest group, and you can find transition metals in this group, such as Iron, Silver, Gold, Mercury, Lead, Copper, etc... 2  zirc is correct, transition metals aren't minerals, they are elements!!  3 Zirc's right, it's silicate.