Hybrid
A hybrid or mixed species was the end result of mixing two or more different species in the biological process of reproduction. Klingons referred to hybrids derogatorily as a mongrel. () Spock was also derogatorily referred to as a half-breed on a number of occasions. (; )

Biological aspects 
Because of the common genetic ancestry of most of the species of the Milky Way Galaxy by way of the ancient humanoids, many species were able to interbreed with or without the help of genetic technology. () 

According to Doctor Phlox, Humans and Vulcans were quite similar. () In fact, Bethany, a Human/Skagaran hybrid, was one of the first known hybrids encountered by Humans from Earth, confirming that such interspecies breeding was possible. ()

Societal aspects 

In some cultures, children who are born as a result of interspecific relations were rejected by the society of both races. For example, Bajoran/Cardassian hybrids were often rejected by both Bajorans and Cardassians. () This was, however, also often the same treatment received by Cardassian orphans as well. ()

During the mid-22nd century, before such things were commonplace, those behind Terra Prime, such as John Frederick Paxton, believed that Elizabeth, a test tube baby-hybrid of a Human and a Vulcan was "a cross-breed freak," asking, "How many generations before our genome is so diluted that the word "Human" is nothing more than a footnote in some medical text?" ()

Personal aspects 

As noted above, Spock, a Human/Vulcan hybrid, had many personal demons when it came to his being.

In 2266, he shared with Doctor Leonard McCoy that "being split in two halves is no theory with me, Doctor. I have a Human half, you see, as well as an alien half, submerged, constantly at war with each other. Personal experience, Doctor. I survive it because my intelligence wins over both, makes them live together." ()

Examples of interspecific reproduction

Aenar 
 Aenar/Andorian
 Talla

Bajoran 
 Bajoran/Cardassian
 Mika and Dukat's child
 Tora Ziyal
 Bajoran/Cardassian/Human
 Laira Rillak

Betazoid 
 Betazoid/Human
 Anita Pierce
 Walter Pierce
 Ral's mother
 Devinoni Ral
 Ral's siblings
 Deanna Troi
 Thaddeus Troi-Riker (¼ Betazoid, ¾ Human)
 Kestra Troi-Riker (¼ Betazoid, ¾ Human)
 Ian Troi
 Kestra Troi
 Betazoid/Human/Klingon
 Shannara
 Eric-Christopher
 Betazoid/Tavnian
 Lwaxana Troi and Jeyal's son

Caitian 
 Caitian/Unknown species 
 Connolly's roommate

Cardassian 
 Cardassian/Bajoran
 See above
 Cardassian/Bajoran/Human
 See above
 Cardassian/Kazon 
 Seska and Culluh's child

Human 
 Human/Angel I native 
 The crewmembers of the Federation freighter Odin were mentioned to have fathered children with the Angel I inhabitants. ()
 Human/Bajoran/Cardassian
 See above
 Human/Betazoid
 See above
 Human/Betazoid/Klingon
 See above
 Human/Boraalan 
 Nikolai Rozhenko and Dobara's unborn child
 Human/Daliwakan
 The Gigolo
 Human/Denobulan 
 Phlox and Amanda Cole's nine children from an alternate future 
 The descendants of Phlox and Cole's nine children
 A part-Denobulan boy
 Human/Greek god
 Apollo
 Human/Ikaaran/Two unknown species 
 Karyn Archer
 Human/Klingon
 See below
 Human/Ktarian
 Naomi Wildman
 Sabrina
 Human/Napean
 Daniel Kwan
 Human/Ocampa
 See below
 Human/Romulan
 See below
 Human/Skagaran
 Bethany (¼ Skagaran, ¾ Human)
 Human/Trill
 See below
 Human/Vulcan
 See below
 Human/Vulcan//Rigelian
 Human corpse

Klingon 
 Klingon/Betazoid
 See above
 Klingon/Human 
 K'Ehleyr 
 Alexander Rozhenko (¾ Klingon, ¼ Human)
 B'Elanna Torres
 Miral Paris (¼ Klingon, ¾ Human)
 Klingon/Romulan
 Ba'el
 Klingon/Trill
 Brota

Ocampa 
 Ocampa/Human
 Linnis Paris
 Andrew Kim

Romulan 
 Romulan/Human
 Sela
 Simon Tarses
 Simon Tarses' brother
 Gabriel Hwang/Pel's unborn daughter
 Romulan/Klingon 
 See above
 Romulan/Vulcan
 Oh
 The Romulo-Vulcans, including Shira

Talaxian 
 Talaxian/Mylean
 Alixia (presumably &frac78; Talaxian, &frac18; Mylean)
 Neelix (&frac78; Talaxian, &frac18; Mylean)
 Talaxian/Mylean/Vulcan 
 Tuvix, a fusion of Tuvok and Neelix, was created by a transporter malfunction with hybridizing flowers.

Trill 
 Trill/Human 
 Yedrin Dax
 
 Trill/Klingon
 See above

Vulcan 
 Vulcan/Human
 Elizabeth (binary clone of Charles Tucker III and T'Pol)
 Lorian
 Spock
 Spock (alternate reality)
 Spock (mirror)
 Vulcan/Romulan
 See above
 Vulcan/Talaxian/Mylean
 See above

Appendices

See also 
 Amalgam
 Bastard
 Unnamed hybrids

Background information 
In an initial story outline of , Charles Evans was referred to as a Human/Ferndok hybrid, since his mother was a Ferndok (a species which, during the episode's development, was later renamed Thasian).

Apocrypha 
In the novel The Ashes of Eden, Kirk discovered the colony world of Chal, a planet briefly colonized by the Romulans and Klingons during an alliance, populated by genetically-engineered Klingon-Romulan hybrids.

External links

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Sex and reproduction