Rabbit
Not a rodent but a lagomorph, with teeth that never stop growing and a gut that runs on hay. Most awake at dawn and dusk, and it jumps for joy.
Overview
A rabbit is not a rodent. It is a lagomorph, and the difference that matters is the digestive system: a rabbit ferments fibre in a large caecum and then eats the result. Those caecotrophs are soft, taken directly from the animal, and they are where much of its protein and B vitamins come from. A rabbit that stops doing it is a rabbit with a problem.
The teeth never stop growing, and hay is what wears them down. Nearly everything that goes wrong with a pet rabbit traces back to too little fibre: dental disease first, and then gut stasis, where the digestive tract slows or stops, gas builds and the animal can die within a day or two. Gut stasis is an emergency, not a case for waiting until morning.
Temperament
Prey animals, and they behave like it. Most rabbits dislike being picked up, because being lifted off the ground is what happens to a rabbit in the wild, and a struggling rabbit can break its own back kicking out.
Get down to the floor instead and they are far more sociable than their reputation suggests. They are also companionable with each other, and a neutered bonded pair is the standard modern recommendation over a single rabbit in a hutch, which is the older way and a poor one.
Care and grooming
Unlimited hay is the whole diet in practice, with a measured amount of pellets and daily greens on top. Muesli style mixes let a rabbit pick out the sugary parts and leave the fibre, which is exactly the wrong outcome.
Check the back end daily in warm weather. Flystrike, where flies lay eggs on a soiled or damaged area and the maggots do serious damage very quickly, kills rabbits every summer and is almost entirely preventable. Long coated breeds need daily brushing to avoid the mats that cause it.
Living and exercise
Space measured in hops, not in cage inches. A rabbit needs room to take three hops in a straight line, to stand fully upright on its back legs without its ears touching anything, and to stretch out flat.
That means a pen or a rabbit proofed room rather than a hutch, with somewhere to hide and something to chew all day. They live eight to twelve years, which is a longer commitment than most people making a first purchase expect.
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