Ark (Doctor Who)

The Ark was a vast, generational spacecraft designed to preserve the human race, which left Earth in the 57th Segment of Time (around AD 10,000,000) as it was plunging towards the Sun. Intended to take humanity to a new world- Refusis II- over the course of 700 years, the Ark was piloted by a small group of humans and their alien allies, the Monoids- a group known as the Guardians. It contained miniaturized samples of Earth's plant and animal life, as well as the rest of the human and Monoid population, in storage. To symbolize the long journey ahead, a giant statue of a human was placed within the Ark.

The first Doctor visited the Ark as it launched, but his sick companion Dodo Chaplet introduced an unexpected wrinkle in the humans' plans- the common cold, long since wiped out on Earth. Although the Doctor was able to concoct a cure for it using animal membranes, the human population was weakened by the forgotten virus. The Doctor and company returned to the Ark near the end of the 700-year journey, only to find that the Monoids had taken over the human population. (The statue had even been changed into that of a Monoid.) The Doctor, in alliance with the Refusians, ensured that the Monoids and humans could stay on Refusis as long as they coexisted peacefully.