This would be the terrestrial megadrile earthworm which are hermaphrodites, which means that each animal has both male and female reproductive organs. When two earthworms mate, both worms typically fertilize each other (no trouble in reproduction)
There are approximately 2,700 different kinds of earthworms. Even though worms don’t have eyes, they can sense light, especially at their anterior (front end). They move away from light and will become paralyzed if exposed to light for too long (approximately one hour). They even survive being frozen if the freeze is not too rapid.
Earthworms do not have hearts but have an organ that carries out the functions of the heart and it is known as the ‘aortic arch‘. Some say they have five hearts.
The great naturalist Charles Darwin wrote this:
…it may be doubted if there are any other animals which have played such an important part in the history of the world as these lowly organized creatures.
Let’s all appreciate earthworms a bit more!