Hybrid

A hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, races, or species resulting in a mixed origin.

Basic Information

Biological Traits

Plants

Plant species are interesting as they hybridize more readily than animals, and the resulting hybrids are fertile more often. In fact many commercially used plant species are the result of hybridization, combined with polyploidy, which duplicates their chromosomes.
Plant species that are genetically compatible may not hybridize in nature for various reasons, mostly due to geographical isolation, differences in flowering period, or differences in pollinators. Species that are brought together by people in gardens may hybridize naturally, or done by people themselves such as altered flowering periods or artificial pollination. Hybrids are sometimes created by people to produce improved plants that have some of the characteristics of each of the parent species. Much work is now being done with hybrids between crops and their wild relatives to improve disease-resistance or climate resilience for both agricultural and horticultural crops.

Animals

People
People groups like humanity, fey, magical beasts, etc. can and often do have hybrid offspring for various reasons.
Human species that hybridize with each other often have kids on a spectrum of intermediate traits like hauflin and homin hybrids. Most are actually fertile but some are sterile hybrids.
The exception are either races hybridizing with Amazons, or more specifically Amazon women. An Amazon woman is more likely to have an amazon daughter as a child, though if they have a male child they are more likely to resemble the race of their father over that of a male Amazon.
Most fey species don't have hybrid offspring that blend parental traits; they either have the majority of one parents traits or another. For example a fairy and merfolk hybrid will either look like a fairy or merfolk, but not have the fairy wings and merfolk fins at the same time. This also seems to be true for fey hybrids with other creature types as well.

Magical beast hybrids are known as hanyou. They are made exclusively when a magical beast in humanoid form mates with a different species as most sapients are incompatible with henge's animal forms.

Spirits

Spirits are inherently incorporeal creatures that under certain circumstances take on a corporeal form. These forms can potentially mate with a naturally corporeal being to make offspring. Unlike spirits, these offspring will have a definite corporeal form with all the requirements needed to keep the creature healthy. As they possess physical bodies with evident biology, they have a similar dependence on internal organ structure.
The offspring will be able to produce spiritual substances like ectoplasm  so their form can become incorporeal like a spirit. They can also acquire energy from PKE but their body would require material food to synthesize compounds and rebuild itself.

Genetics and Reproduction

Interspecies Offspring

Hybrids generally come in two (arguably 3) varieties.
Co-dominant Hybrid: Offspring has a blend of both parents traits
Hauflin × Homin
Hauflin × Elf
Homin × Elf
Amazon × Elf
Fairy × Elf
Hauflin/Homin/Amazon × Most Magical Beasts
Human, Fay, Magical Beast × Jinn
Human, Fay, Magical Beast × Elemental
Human, Fay, Magical Beast × Divinity
Divinity × Succubus
Divinity × Elemental
Divinity × Dryad
Divinity × Jinn
Distinct Offspring (Either/Or): Children (usually) physically appear to be the same species as one parent or the other — not a blend of them. Commonly called "either/or" offspring.
Hauflin x Amazon
Homin × Amazon
Hauflin x Fairy/Merfolk/Giant
Homin x Fairy/Merfolk/Giant
Fairy × Merfolk/Giant
Merfolk × Giant
Dryad × Humans/Most Magical Beasts/Most Fey
Co-dominant hybrid × either parent species

Dominant Reproduction: Offspring produced by interspecies relationship are always the former species. Common if species is female only and thus only gives birth to its own kind. As such these offspring are not really considered "hybrids" despite having parents of different races.
Lamia × Humans, Most Humanoid Fey, Most Magical Beasts, Most Humanoid Spirits
Harpy × Humans, Most Humanoid Fey, Most Magical Beasts, Most Humanoid Spirits
Alraune × Humans, Most Humanoid Fey, Most Magical Beasts, Most Humanoid Spirits
Jorogumo × Humans, Most Humanoid Fey, Most Magical Beasts, Most Humanoid Spirits
Yukionna × Humans, Most Humanoid Fey, Most Magical Beasts, Most Humanoid Spirits
Succubus × Humans, Most Humanoid Fey, Most Magical Beasts, Most Humanoid Spirits

Incompatible: Can't produce offspring together so no hybrids, sorry
Lamia × Harpy/Jorogumo
Harpy × Jorogumo
Jorogumo × Yukionna
Yukionna × Lamia/Harpy
Yukionna × Humanoid Spirits
Alraune × Harpy/Lamia/Yukionna
Succubus × Lamia/Harpy/Jorogumo/Yukionna/Alraune
Harpy × Harpy
Alraune × Alraune
Yukionna × Yukionna
Jorogumo × Jorogumo
Succubus × Succubus
Dryad × Ignan/Slyph elemental

Anthropoids

*notes Humans= homins, hauflins, amazons
Fey= fairies, elves, merfolk, lamias, harpies, giants, alraunes
Magical Beasts= jiuweihu, tanuki, bakeneko, okurinu, usagi, jorogumo, drakains
Spirits= jinn, elementals, succubi, dryads, divinities
Synthetic= Anthropoids

Civilization and Culture

History

The history of a hybrid's treatment in society is usually on a case by case basis. There is generally an idea that hybrids were treated terribly in the past and things are much better now, which is only partially true.

Hybrid Characters
Suleiman: Jinn/Homin