Mammals:
* Gaur: A large wild ox found in Southeast Asia
* Gorilla: A large, intelligent ape found in Africa
* Gazelle: A graceful antelope found in Africa and Asia
* Giraffe: The tallest mammal on Earth, known for its long neck
* Gnu: A large antelope with a distinctive beard, found in Africa
* Gibbon: A small, agile ape found in Southeast Asia
* Gerbil: A small rodent with a long tail, found in deserts
* Goat: A domesticated mammal known for its milk and meat
* Guinea Pig: A small, domesticated rodent popular as a pet
Birds:
* Gull: A seabird with a distinctive call
* Goose: A large waterbird known for its honking sound
* Grouse: A type of bird found in forests and grasslands
* Gadwall: A duck with a distinctive black and white pattern
Fish:
* Gar: A long, slender fish with a bony snout
* Grouper: A large, bottom-dwelling fish found in warm waters
* Goby: A small, bottom-dwelling fish found in many habitats
Reptiles:
* Gecko: A small lizard with sticky toes
* Gila Monster: A venomous lizard found in the southwestern United States
* Green Iguana: A large lizard that is a popular pet
Insects:
* Grasshopper: A jumping insect with long hind legs
* Giant Water Bug: A large, predatory insect that lives in water
* Glow Worm: A type of insect that produces light
This is just a small sample of the many animals with the letter "G" in their name. There are many others, including amphibians, reptiles, insects, and even some extinct animals.