### animal:

Companion animal
* Most companion animals feel safest and happiest in their own home environment
  - have considerably less body mass than an adult human
* are easily susceptible to frostbite.
* can help humans improve trust, memory, self-esteem and concentration
  - mitigate the effects of loneliness, and other stresses
  - positively influence child development
* have more consistent behavior, compared to humans.
* suffer from a variety of infectious diseases.

Complex animal
* All complex animals start out as a single cell which grows and divides many times.
* More complex animals have a digestive tract.
* Some complex animals have simple eyes, whereas some simple animals have complex eyes.
* can control the quality of the interstitial fluid.
* have internal surfaces specialized for exchange with external environment.

Countless animal
* find shelter.
* play roles.

### animal:

Critter
* Many critters hatch out of eggs without any help from their mamas and survive just fine.
* Most critters come from sea
  - eat plants
  - has-part legs
* Most critters have feet
  - inhabit environments
* Most critters live in communal dens
  - forests
  - make faces
* Most critters occupy human intestinal tracts
* Some critters are in foster care because they're seriously ill or injured.
* Some critters eat ants
  - berries
  - cicadas
  - fish
  - grubs
  - phloem
  - feed owls
* Some critters have resistance
  - shells
  - invade vegetables
* Some critters live in plants
  - wetland
  - on beaches
  - make snacks
  - play in baskets
  - use sand
* also make a great first pet for children wanting an animal companion to call their own.
* are animals
  - bands
  - our handmade teddy bears in three sizes
* can enter the home through cracks or crevices in the walls, so seal off any openings
  - move
  - in all shapes and many sizes
* commute between environments via tunnels and bridges.
* eat energy
* forage at nights.
  - no depth perception
* includes brains
  - cell membranes
  - cells
  - corpi
  - cytoplasm
  - heads
  - nuclei
  - plasma membranes
  - sections
  - skulls
  - vacuoles
* is an animal
* lift heads.
* need habitats.
* require care.
* text search program that is designed to be easy to use.
* time their reproductive cycle to maximize the chances of their babies' survival.

### animal | critter:

Slimy critter
* Most slimy critters have feet.
* Some slimy critters have shells.

### animal:

Cygnet
* Many cygnets succumb to cold, wet weather, parasites, insufficient food, or predators.
* Most cygnets eat animals
  - aquatic insects
  - have necks
  - possess feathers
* Some cygnets have bills.
* add some smaller crustaceans to their meals as well.
* are swans
  - young birds
* can swim as soon as their down is dry, but they stay on their nests for a few days.
* includes air sacs
  - bird's feet
  - bone cells
  - breasts
  - chest cavities
  - chests
  - faces
  - flight feathers
  - ground substances
  - heads
  - lips
  - marrow
  - mast cells
  - mouths
  - quill feathers
  - rib cages
  - second joints
  - sections
  - skulls
  - sterna
  - talons
  - wishbones
* remain with their parents throughout their first winter.
* require an abundant supply of aquatic insects, crustaceans, and aquatic plants.
* usually eat bugs instead of weeds and grasses.

Dangerous animal
* Most dangerous animals roam oceans.
* Some dangerous animals injure animals
  - domestic animals
* Some dangerous animals kill domestic livestock