Interesting fact about biology!
Source: Wikipedia
Ever heard of this term?
Defination of hermaphrodite: A person born with both male and female sex organs.
Hermaphroditism do occur in animals, plants and even HUMANS!
In many species, hermaphroditism is a common part of the life-cycle, particularly in some asexual animals and some plants. Generally, hermaphroditism occurs in the invertebrates, although it occurs in a fair number of fish, and to a lesser degree in other vertebrates. For hermaphrodites that belong to a species in which hermaphroditism is not normal (humans, for example), reproduction is mostly impossible.
There are several types of hermaphrodites in animals.
Sequential hermaphrodites
Sequential hermaphrodites are organisms born as one sex which later change into the other sex, and can only function as one sex at one time. A few species in this group can sex change multiple times, but they can only function as one sex at a time.
Protandry: The organism starts as a male, and changes sex to a female later in life.
Example: The Clownfish
Protogyny: The organism starts as a female, and changes sex to a male later in life.
Example: Wrasses
(Go check them up!)
Simultaneous hermaphrodites
A simultaneous hermaphrodite (or synchronous hermaphrodite) is an organism that has both male and female sexual organs at the same time as an adult. Usually, self-fertilization does not occur.
Hamlets, unlike other fish, seem quite at ease mating in front of divers, allowing observations in the wild to occur readily. They do not practice self-fertilization, but when they find a mate, the pair takes turns between which one acts as the male and which acts as the female through multiple matings, usually over the course of several nights.
Gonadal dysgenesis
Gonadal dysgenesis is a type of intersexuality formerly known as "true hermaphroditism". It occurs in about one percent of mammals, including human beings, but it is extremely rare for both sets of organs to be functional; usually neither set is functional. In humans, these manifestations are often altered (sometimes only cosmetically) to resemble standard male or female anatomy shortly after birth.
You can try checking these sites out to know more about gonadal dysgenesis, but please don't mind the content.
http://www.angelfire.com/ca2/BornHermaphrodite/
http://www.rotten.com/library/sex/hermaphrodite/
I hope you've learnt more about something!