If you have found an injured or orphaned wild animal, go to Animal Help Now to find the nearest licensed wildlife rehabber near you and take it there as possible, without attempting to feed it.
Did I find an orphaned baby ___?
First- how do we know it's an orphan? Seeing a dead ___ on the roadside does not mean that it is the parent of this ___. Many wild parents only see their offspring a few times per day; they do this to keep from alerting predators to the presence of their young. If you suspect that young have been orphaned, see if you can place a small twig over the entrance of the nest/den so you can see if it's been disturbed within 24 hours.
But, I touched him; surely the mother will abandon him, since he smells like people! Actually, most birds don't have any sense of smell at all; and while most mammals will think their young are stinky now- like most parents, they'll just make them take a bath!
Now, do we know it's a baby?
Wildlife doesn't have the luxury of long childhoods. Opossum young are completely independent of their mother at around 3 months old & 6-7 inches long. Cottontails are weaned by 1 month of age. If a young bird can grip with its feet, it should be placed on a branch at the nest site; while not fully independent, the parents will assist.
No human care can equal maternal care. Please remember that human care is a last resort, not a chance to have a cool experience raising someone that's been kidnapped from a caring parent.
If you need to keep an animal overnight until you can bring it to a licensed rehabber, keep it in a small, dark, quiet place, in as small of a container as possible to avoid it thrashing around and hurting itself. Please do not offer it food or water or milk as even these actions can cause the animal harm in some situations.