Hindu gods and goddesses and their vahanas (vehicles) are a peculiar concept in Hinduism. I have not come across this concept for the gods of other cultures. I have heard about ravens working as servants of a Viking god, Odin.

What Do Vehicles of Gods/Goddesses Represent?

Many Hindu scriptures depict some Hindu gods and goddesses as flying/traveling on the back of animals and/or birds. The animal/bird on which the particular god/goddess travels is called his/her vahana (carrier). Sometimes, they are also depicted as standing or sitting near the vahana. Some deities have more than one vahana. Some interesting stories are about why a particular animal is the vahana of a particular deity. It is hard to tell if there is any hidden meaning behind it, or if it is just to give protection to animals.

E.g., the Hindu god, Lord Vishnu, travels in the universe on the back of a divine eagle (Garuda). Therefore, an eagle is the vehicle of Lord Vishnu. However, it is unclear whether it is a real eagle or the spaceship of Lord Vishnu, which is depicted as an eagle by ancient Hindus.

If we assume it is a bird, then the question arises of how it can travel in space without oxygen. The answer can be that it is a divine bird and not like ordinary eagles so that it can travel in space. Hindus worship Garuda as a god.

If it is a spaceship, then it is quite possible that our ancestors could not imagine anything like that as that technology was far more advanced then, so they mistook it for a bird.

Another possibility is symbolization. Symbolization is widely used in Hindu scriptures.

E.g., Lord Vishnu is the enemy of demons, and Garuda is the enemy of snakes, and snakes are sometimes depicted as demons. Hence, Garuda is the carrier of Vishnu.

Another example could be:  The bull is the carrier of Lord Shiva. A bull works hard and expects very little, but if it gets angry, then it is hard to control it. Bull also represents strength. Lord Shiva also does not get angry readily, but it is mayhem for the enemy if he gets angry.

List of Hindu Gods and Goddesses and their Vahanas (Vehicles):

God/Goddess                    Vehicle

Indra                                          Airawat (A white elephant with five heads).

Bhumi                                        Elephant.

Ganesha                                    Mouse.

Shiva                                          Bullock.

Dattatreya                                  Cow.

Vishnu                                        Eagle.

Brahma                                      Swan.

Kartikeya                                    Peacock.

Durga                                         Tiger or Lion.

Saraswati                                   Swan.

Sun                                            A golden chariot pulled by seven white horses.

Agni (Fire)                                  Male Sheep.

Lakshmi                                     Owl.

Shitala Devi                               Donkey.

Yama                                         Male Buffalo.

Ayyappa                                    Tiger.

Narmada                                   Crocodile.

Ganga                                       Crocodile.

Yamuna                                    Tortoise.

Vayu                                          Antelope.

Chandra (Moon)                      Antelope.

Shani                                        Crow.

Kubera                                      Man.

Daksha                                     Man.

Kamadev                                  Parrot.

Bhairava                                   Dog.

Kalki                                         Horse.

Ushas                                       Cow.

Manasa                                    Snake.

Rati                                          Pigeon.

Pushan                                    Chariot of goats.

Alakshmi                                 Crow.

Ketu                                        Vulture.

If you have more information about Hindu Gods and Goddesses and their vahanas (vehicles), please share them.

References: https://en.wikipedia.org/wiki/Vahana