One of the themes sometimes appearing in fantasy are half-bloods/half-breeds/hybrids (whichever term you prefer), most often between different humanoid species. Today, I’ll share my thought about them.
A bit of biology first…
As I am focusing on humanoids, I’ll ignore plant hybrids for the purpose of this post. Anyway, the creation of a hybrid species is, in natural conditions, very rare: not only the species need to be compatible but they also need to have overlapping habitat. The latter is the main issue: if two similar species developed for a specific habitat, they’d not overlap with a species evolved for a different one.
My favorite example would be the liger – an offspring of male lion and female tiger. Tigers and lions don’t share any habitat currently and even before humans started reducing their habitats a few centuries ago, the overlaps were minimal and thus these hybrids were very rare.
Most of know hybrids come from the same genus of animals: equine hybrids (mule, zonkey), nanulak/pizzly (polar + grizzly bear hybrid), wolfdogs, several feline hybrids, and more. If there’s a genetical incompatibility, the resulting hybrid species might be sterile. There are many factors – and for those interested in the topic, I’d recommend having a look at some scientific articles/research.
…and back to fantasy
Now, for the purpose of this post, I will not take disfiguration or curses into account (for chimera-type beings) as those are usually not a product of procreation.
A half-breed I believe to be the most typical is a human-elf half-blood. It’s not as limited, though. I’ve seen half-orc hybrids (Garona as half-orc half-draenei in World of Warcraft, half-orc half-human hybrids exist in fantasy as well) as well and I’m sure I’ll encounter more as I read more books. Mytholog and fantasy both use the concept of Nephilim – half-breed between demons and humans, or demons and angels, depending on the approach (and with different versions of spelling).
Often, the species are close in body bulk – which makes sense from a biological perspective: major size difference will make successful mating a challenge.
In general, half-breeds tend to be rare and, in many cases, shunned and/or victims of racism. Through this, they might be a way to show more about different species in a fictional world and the relations between them…
One of the main reasons why half-bloods might be rare is that different humanoid species will favor different places to live, have different priorities,, lifestyle, territorial aims, and such.
Pairings of species with long-lasting feuds or even war between them will be extremely rare. Furthermore, their parents might be seen as traitors and their offspring shunned – to the point of a forced exile. Such situation makes a large half-breed population unlikely.
Yet, even in times of peace, there are still differences in habitat, lifestyle, and what each species considers attractive. Unless there are individual on both sides who consider the other side attractive and have the will to change their lifestyle for the other, it’s unlikely the species would cross-breed: a typical elf would not be fond of living in a city of brick or stone, and the typical human would probably not be fond of elven lifestyle in the traditional sense (wooden dwellings in the forest). Even the ‘high elf’ approach (elves living in cities) bears challenges.
Biological and psychical challenges
First challenge one should consider is procreative compatibility: a species giving birth via eggs would probably not be compatible with a mammal due to differences in mating and prenatal development (so be careful if you decide to try, for example, a dragon-human hybrid and make sure their existence is explained).
Another major difference is lifespan: depending on approach, a human’s natural lifespan can be anywhere from 40 to 100 years (depending on setting) while elf’s lifespan can be anywhere from a few centuries up to almost unlimited.
It’s likely that a halfblood would have lifespan somewhere between – which means significantly outliving one of parents but far from the lifespan of the other. This might bear psychological issues to both the parents and the child: it’s likely any sentient species would have some awareness of mortality and some default view on the usual age of natural death.
A half-blood with an unique lifespan would face two main issues in this regard: different lifespan than both parents and lack of potential partners with the same lifespan (unless half-bloods are a common thing in their setting). This could lead to feeling of isolation, abandonment, and eventually to mental issues and struggling with finding one’s place in life.
The half-blood’s parents would face similar dilemmas: one of them knowing they’ll outlive their mate by centuries (if not more) and likely the same with their child and the other to barely see them reach adulthood, let alone their primes.
In conclusion, I think the burden of different lifespan (and I’ll touch the topic of fantasy longevity soon) might be one of the main reasons why half-bloods are usually rare.
I’m wrapping it up here. I’ll welcome your thoughts and comments. Have you encountered a book where this was approached well? Are you writing a story where half-breeds play a role? Feel free to share.