Editing Half-Dwarf (section)

== Genetic Explanation ==
The reason for why humans, elves and orcs can interbreed but not dwarves can be simply explained. Humans, elves and orcs are not species but rather races or "breeds" (or separate species that are still in the same genus, depending on whether half elves and half orcs are fertile in your world), while dwarves ''are'' in an entirely separate genus.

Consider dogs, our trusty ''canis lupus familiaris''. A pit bull and a great Dane can have puppies with each other because, although there physical characteristics are significantly altered, their overall genetic code is similar enough to allow reproduction hence we can get things like Labradoodle (this would still be possible even if they were different species in the same genus, but then the labradoodle itself would be infertile like a mule). It also means that breeds of dogs and cats also have a much higher tendencies for genetic defects as to get the traits we want we often breed dogs with their siblings to exaggerate what we want at the cost of recessive diseases also becoming more common.

Now lets consider D&D, with active deities loose in the world with plenty of time it very conceivable that at some point in the distant past the gods selectively started to alter traits in some single humanoid species (Let's call her [http://en.wikipedia.org/wiki/Lucy_(Australopithecus) Lucy] for LOL's) to create the human, elf and orc races much as we altered wolves to create our dog breeds. [[Corellon Larethian]] is said to be the god of the elves and would be responsible for creating them, while [[Gruumsh]] made the orcs and the infamous battle between the two that cost Gruumsh his eye would be the result of an argument over what form the elf/orc race would take. 

The observant would note that this would mean we should see Orc/Elf hybrids in the game, however consider the size difference between and Orc and an Elf. Why it's true that you can breed a female Chihuahua and a male great dane (the inverse would require a ladder), the Resulting puppy causes significant problems for the mother. So an Orc male, female Elf would need a C section, at best, in order for the baby to be born at all. Orc Female male elf on the other hand is distinctly more viable but, and lets be blunt, this situation is much less likely then an Orc male elf female combination because the Orc woman would likely find his scrawny elf dick somewhat underwhelming. On the subject of alignment as anyone who has owned dogs knows is that dog breeds have differing temperaments and attitudes explaining the fixed good and evil alignment of most races. That humans are far more Alignment flexible suggests that they are the "base" species and the gods created the Elf and Orc races from humanity leaving the unaltered humans to develop on their own. (Though in 5e they actually explain it as being because most races have a patron god or pantheon of gods telling them how to behave, whereas the human one was killed very early on in the world's history. This is supported by the Ebberon setting, which has a giant magical barrier keeping even outside gods form getting in, and as a result everyone behaves completely different there)

However, remember that there are dozens of human ancestors any that while close to human, are distinct species and would run into the Mul situation mentioned above of any half breed being sterile (except when they weren't).

So while some gods chose to use Lucy as the base line for their projects, other gods chose to use a different base structure. For the Dwarfs [[Moradin]] chose to start with Neanderthals removing traits he disliked and adding traits he did (you could almost say he '''forged''' them), [[Yondalla]] created Halflings likely from [http://en.wikipedia.org/wiki/Homo_floresiensis Homo Floresiensis] the Human "Hobbit". The hobbits would likely also be a good starting point for the Gnomes, however no Gnome Halfing hybrids. Another good candidate for who [[Garl Glittergold]] used to create the Gonme race would be the [http://en.wikipedia.org/wiki/Denisovan Denisovan] which were discovered in a cave in 2012 and in the 3.5 hand book Garl is not said to have created the Gnomes, but having discovered them. Now, admitly we find a lot of Homonids in caves but what the Denisova have going for them is that they coexisted with Humans and Neanderthals making them a likelier candidates then other homonids. 

All three races, Gnome, Dwarf and Halfling all lack hybrids and they all have deities who claim a specific role in there creation thus forming a reason why we don't get Dwarf, Gnome and Halfling hybrids, because they are different species of hominid, rather then being a different breed.