Image recognition technology has advanced much in recent years. We now have services such as Google Goggles that allows regular users to make use of this technology.
This technology allows computers to take a digital image, and deduce what objects are in the picture. This is very easy for humans, since most people can identify fairly quickly what is in a picture fairly quickly. Although it is very easy for humans, this is a very hard task to do with computers. It is currently a very active area of research.
Although it is still far from perfect, it may be possible someday to build something that would be able to identify animals and plants just from taking a photo.