this bird is the only one that can fly backward
hummingbird
this planet is slightly larger than our moon
Mercury
the cause of different seasons
the tilt of the earth's axis
baby frogs
tadpoles
this is the type of blood fish have
cold-blooded
this bird is the largest in the world
ostrich
this planet is called "Earth's twin"
Venus
the cause of all weather
sun
young amphibians breathe with these
gills
the breathing organs of fish
gills
this bird is the South American relative of the ostrich
rhea
this planet has a moon larger than Mercury
Saturn
the amount of major wind systems
three
amphibians protect themselves with this mildly poisonous substance
slime
the substance a shark's skeleton is made of
cartilage
this bird can dive through the air at speeds of 220mph or more
peregrine falcon
this planet is where a Viking spacecraft landed
Mars
the cause of dew and frost
condensation
the process in which an animal changes form as it grows older
metamorphosis
most fish belong to this group
bony
this bird encloses itself in its nest with a mud wall
hornbill
this planet has the strongest winds measured anywhere in the solar system
Neptune
the amount of water vapor that the air can hold at a given temperature
relative humidity
the largest salamander
Japanese giant salamander
this type of fish has both of its eyes on one side of its head
flounder