A billion years ago, two single bacteria joined forces. One searched for things to eat. The other extracted energy from this food and turned it into the fuel for both organisms to live.
Eventually, the two merged together and became one ‘animal’. The ancestral DNA of the second bacteria species lives on in every cell of your body and every other animal on Earth as ‘mitochondria’. Without these, we could not eat or live … read more >>>
Animal cell mitochondria showing the circular DNA shared with bacteria. Drawing, Simon Mustoe.
