Saiyans & Humans - Same Species

[TheAsterisk!]

I have come to the conclusion that Saiyans and humans are the same species based on the happenings of tthe manga and anime series.
In order for two animals (opposite genders) to have offspring, they must either be of the same species or (if not the same species) have the same number of chromosomes in each cell. This is the case with a donkey and a horse can create a mule. The problem is this offspring is sterile (cannot reproduce). The only way two animals can have fertile (capable of reproducing) offspring is for those two animals to be of the same species. That is, in fact, a good definition of species. This is why all domesticated dogs are the same species but merely different breeds.
I'm thinking that saiyans and humans are a bit like that: different breeds but same species.

We know that humans and saiyans have the same number of chromosomes as soon as we know of Gohan (as with Trunks and Goten later on), but we don't really know they're the same species 'til we have knowledge of Pan (and that is at the very end of Z (it's even in the manga), not the beginning of GT as has been claimed in this forum). Since Pan is known to be the (genetic) daughter of Videl (a human) and Gohan (a human-saiyan hybrid), we know Gohan is fertile, demonstrating that saiyans and humans are of the same species.
WHAT CONSPIRACY LEAD TO THIS COMPATIBILITY?
I'm posting here to fish for answers to even greater questions that stem from these observations.

How could there be populations of the same species on different planets without knowledge of each other? How did they come to be separated? Why didn't Gohan, Bulma, Dr. Briefs or Dr. Gero, the resident smarties of the Dragonball world, ever think of this?

I eagerly await your hypotheses...

[Hideki Motosuwa.]

The anime/manga was made for kids, and my hypothesis is that the creators wouldn't want to confuse the kids with these questions. To me, I guess the DBZ geniuses didn't want to know about the different lives on different planets(though the technology was available). In the DBZ world, Dinosaurs, talking, shape-shifting pigs and even aliens on Earth is normal enough,(and the fact that the planet Vegeta was in another galaxy). If you lived with these life forms already, would you still be concerned about the Saiyans? Hope I helped even a little!

[Ami~chan]

I have a feeling the creator didn't care much about the science aspect of it all.

All he cared about was the butt-kicking, energy attack, kung-fu aspect of it.

Besides, Saiyans could have some funky kind of genes that allow them to mate with certain other species, and produce fertile offspring. You never know what those aliens can be capable of.

[TheAsterisk!]

I was hoping for paranoid, in-story, more entertaining conspiracy theories, just to let you know. I'm not looking for serious answers, just some fun, convoluted, utterly ridiculous reasons why saiyans and humans may have fertile offspring.
Here's an example:
Saiyans, aliens? Pfft, They're shunned mutants with psychological disorders. They were all sent to live in a colony under the sea, but Goku escaped. Eventually, the rest escaped, but due to their disturbed states of mind, they invented the whole story about Planet Vegeta. All of DBZ/GT after the arrival of Raditz is one of Kami's hallucinations brought on by his use of Mr. Popo's hookah*. Everyone knows that Goku & Vegeta are really just humans.
That's a bizarre yet entertaining explanation, the type I'm looking for here. I already know Dragonball ignores basic chemistry and physics.


* Wikipedia only mentions tobacco, but I'm sure you can all figure out what substance Mr. Popo prefers (smirks).

[Alias-Revolution]

T_T I love this article... The logic behind it is so leet...

Anyway...

Knowing that the show is based in a futuristic world, one can assume that genetic engineering has advanced far beyond our current capabilities. I mean, come on, they store a spaceship in a pill. =/

That said, is it not reasonable to assume that some evil genius like Dr. Gero found another perfectly inhabitable planet and used a form of genetic engineering to increase the natural chi flow of certain beings, cross them with their primordial ancestors, and send them to live on their own planet, thus becoming the first man to create a whole new breed of super-humans?

This also raises a question about Namecians. Could they not be a cross-over as well? Say, frogs and humans? If Hitler can experiment with humans, why not some other evil-genius in the future?

On a side note, the last thing I want to do is offend anyone. I am not trying to imply that we are the o ly inteligent beings in existace, and I am most certainly not trying to imply that Hitler was right in hs experiments. If I offended anyone, I do apologize. I was merely theorizing.

[TheAsterisk!]

T_T I love this article... The logic behind it is so leet...

Anyway...

Knowing that the show is based in a futuristic world, one can assume that genetic engineering has advanced far beyond our current capabilities. I mean, come on, they store a spaceship in a pill. =/

That said, is it not reasonable to assume that some evil genius like Dr. Gero found another perfectly inhabitable planet and used a form of genetic engineering to increase the natural chi flow of certain beings, cross them with their primordial ancestors, and send them to live on their own planet, thus becoming the first man to create a whole new breed of super-humans?

This also raises a question about Namecians. Could they not be a cross-over as well? Say, frogs and humans? If Hitler can experiment with humans, why not some other evil-genius in the future?

On a side note, the last thing I want to do is offend anyone. I am not trying to imply that we are the o ly inteligent beings in existace, and I am most certainly not trying to imply that Hitler was right in hs experiments. If I offended anyone, I do apologize. I was merely theorizing.

Good! (cackles) GOOD! This is the kind of stuff I was hoping for!
As for the Namek(ian)s, I say they're snail/human/vine hybrids. They are asexual (snails), have a basically humanoid shape, never need to eat (-> plants?), have silly names (-> snails*), and have antenae (snails).

*(S)Nail, Dende(n), (Es)Cargo, Slug

[Lelouch of the rebellion]

well im no expert but:

The saiyans and humans share same number of chromosomes 46

There offspring is fertile meaning they have complete compatibility.

The missing link is the Saiyan, a Ape Humanoid with enough knowledge to travel galaxies before the modern age.

They then found out that their was only a man and a women saiyan and the inbreeds took over. That caused them to be stupid. Those little people were the ones that didn't interbreed and took the dumb inbreeds technology.

[Odanuki86]

It would be far more likely in my opinion that planet vegeta was simply like earth, posibly more violent weather, but so much so that evolution went nearly the path with most of the creatures ending up the same or very nearly. That may explain the strength, and also the other shorty's intelectual capabilities. The intelect would explain their size as well...thats the way I see it anyway...though on a more realistic side you'd just have to bare in mind thats its only a show and the creater more than likely just didn't bother his self over the details....Almost forgot...as far the nameks I couldn't say why they would end that much like humans but the hands would be for the need to make things such their homes and such, and the antenae, well they seem to have unusualy high sensing abilities...oh and there are many asexual creatures as well inluding plants if I'm not mistaken...they to me would just be an evolved plant, though I couldn't explain their strength...their planet's weather and other various forces seemed pretty calm.

[TheAsterisk!]

Tsk, tsk...
Two animals (male & female) with the same number of chromosomes can produce offspring BUT THAT OFFSPRING WILL NOT BE FERTILE UNLESS THE PARENTS WERE THE SAME SPECIES. This is why mules (a horse mated with a donkey) are all sterile; the horse and the donkey have the same number of chromosome pairs but they aren't the same species. If the Saiyans and humans merely had the same number of chromosomes but were not the same species, then there would be no Pan. Since Pan exists, we can judge that Gohan is not sterile and so Saiyans (represented by Goku) and humans (Chichi) are, in fact, the same species.
Second point...Chewbacca is the missing link. Everybody knows this.
"Those little people" are the Tuffles, if you're talking about the little midgets with laser rifles who get stomped out by the Saiyans as King Kai tells Goku of the Saiyans' history. They have been said to be another species, but, the way things have gone, I wouldn't make a conclusion either way concerning them.
The Namekians' names were supposed to be a weak joke about snails. I'm pretty sure Toriyama said this at some point. That's where my comment came from.
If the Saiyans evolved on Planet Plant/Vegeta, I would expect them to be shorter so that they could more easily withstand the increased gravity (10x Earth's), not monstruous as are all but Vegeta and Goku. I also find it horrendously improbable that two species so removed from each other could evolve so that they exhibit complete genetic compatibility, especially with such an outstanding feature as a tail.
As such, I want my conspiracies!