As anyone from Recycling will tell you, the Asimov runs on algae. From the nutrient slurry that is processed by fabbers into something resembling food, to the scrubbing of carbon dioxide from the atmosphere and conversion to oxygen. The oxygen gardens may look nice, but ultimately can't compare in efficiency to the algae vats distributed around the ship (mainly in the low-g portions).

Tending the algae vats is a dull job for the most part, but one of the more critical functions of the Recycling department. Occasionally Engineering gets involved if things break down, and it's not unknown for Health to have side-projects of their own growing algae that have specific properties.

The oxygen gardens are rare islands of real greenery amongst the metal and plastic of the rest of the ship. Scattered around the ship in various sizes, their primary purpose seems to be to give the crew some variation in their environment, and serve as an ecosystem-in-a-bottle for a few of the shipboard animals and insects. They also process oxygen to a more limited degree, but their name is somewhat of a misnomer since most of the actual oxygen production is handled by the algae vats.

Example plants to be found in these forests include spider plants, snake plants, areca palms, lilies, ferns and the occasional tree of varying species. These appear to have been selected variously for their efficiency, aesthetic qualities, and hardiness.

The largest oxygen garden onboard the ship is the Oxygen Forest, found on Toroid 2, where it takes up the living space of two entire sectors. Quite why the toroid is designed like this is a bit of a mystery, as it seems like a waste of space. Still, there are people who actually live in the Oxygen Forest and Harmony has a tendency to send overworked people there “for their health”.

There are a few parts of the ship dedicated to the preservation of plant stock from ancient times. A vast seed bank contains examples of a huge variety of plants, and many of these are grown cyclically in greenhouses onboard in order to maintain and replenish the stocks and cultivate new species. While it's rare that entirely new species are grown, there is ongoing work into making various existing plants hardier and more plentiful for future use.

Officially speaking, there are no animals on the Asimov larger than a small lizard. Unofficially, some of these lizards get pretty big, growing to a foot or two in length. The majority of the Asimov's fauna is made up of a large number of insect species that typically live in the oxygen gardens.

Lizards of various sizes are found all over the ship, either kept as pets or at the top of the food chain in the oxygen gardens.

Some are kept for lizard-fighting, a barbaric but popular sport in shadier areas of the ship where two or more lizards are dropped into a pit and bets are taken on which one will walk away alive. Alternatively, there's good eating on a lizard, if you know someone who can get a steady supply - real meat is a delicacy compared to the “almost-meat” that gets served as food.

There are a thousand species of arthropod onboard the Asimov, maybe more. They typically stick to the oxygen gardens - those that stray outside are despatched by robots or occasionally by Recycling. They vary from small buzzing things that pollinate flowers, to crawling things that scurry across the floors, to slightly larger ones that will sting or bite you if you bother them. Most of them appear to serve a vital function in the ecology of the oxygen gardens; those that aren't useful prove remarkably difficult to eradicate.

Rats are a pest, and Computer has demanded that they be exterminated wherever they are found. On the other hand, there's good eating on a rat too.

Basic Operations Bots AKA BOBs (or Barely Operational Bastards) are a general-purpose robot that mostly aids in repair and maintenance functions, though they'll sometimes be found performing other tasks throughout the ship.

A typical BOB consists of a wheeled or occasionally legged body, with a telescopic arm attachment. This arm can be outfitted with a range of tools as appropriate, or alternatively comes fitted with a grasping attachment for carrying items. If you had a good enough reason to take one apart (Computer typically disapproves of “experimenting” on vital ship resources) you would find that they are remarkably simple and easy to retrofit. They appear to be fairly difficult to hack, though, since they are connected wirelessly to the ship's network for a lot of their behavioural processing. It's a skilled hacker indeed that manages to get a BOB to do anything on its own.

Micro-reclamation bots, more usually known as Ants (apparently for their resemblance to an ancient insect) get to the places the BOBs can't reach. Their primary function appears to be reclaiming small materials, tidying corridors and compartments, and generally getting to the hard-to-reach places. They mostly come out at night, and appear to avoid people where possible.

Since ants are seen less often than BOBs, and are harder to track through the ship, they are regarded with a sense of mystery. There are a number of superstitions that have grown up around them, most notably that stepping on them is seriously bad luck (and of course there's the apocryphal tale of the child who enjoyed killing ants one day being carried off to Reclamation by a horde of them - though that's mostly used by carers to frighten small children).