[Banestorm] The war of Megalos against Caithness

[hal]

Originally Posted by Bruno

Half-breeds are not required to be sterile. Going back to the ever present example of tigons and ligers, male ligers are IIRC sterlile, and the females are fertile (I could have that backward). AFAIK, both genders of tigons are fertile, but it could be male-sterile female-fertile again. I'd have to go google it and I'm posting this very quickly before work >.>

First I've heard of Ligers and Tigons :) I learn something new every day. Some days I even learn three things.

In any event, it would be interesting to determine how this "fertility" aspect works. Tigons, if they can reproduce together and produce more Tigons would seem to show that it is possible to have half-breeds of two seemingly distinct "species". Problem with that however is whether or not they are truly different species. I seem to recall (and take this with a HUGE grain of salt as I am relying on my memory here!) that they did a genetic mapping of two different species of dogs and found that there was no genetic difference by looking at the genes alone. Also, the question rears its ugly head with wolf-dog combinations.

I guess what it boils down to is whether or not the half-breeds can mate with each other and produce "pure" hybrids. If so, does this mean that the two parent species are more related than we thought, or does it mean they are truly capable of reproduction cross species.

[sir_pudding]

Originally Posted by hal

First I've heard of Ligers.

"It's basically my favorite animal." -Napoleon Dynamite

[hal]

Originally Posted by sir_pudding

"It's basically my favorite animal." -Napoleon Dynamite

No! Not the cult leader Napoleon Dynamite!!!! RUN! ;)

[Anthony]

The traditional definition is that crossbreeds don't breed true, not that they're sterile. If they breed true, it implies that the parents are in fact substantially variant versions of the same species, rather than being different species at all.

Note that, with real (vs fantasy) biology, for males, you can associate a parent species with the 'X' and 'Y' chromosomes, which means gender will determine whether the child is a cross or a purebreed.

[Rupert]

That presumeably requires that all the differentiation is carried on the X (or possibly Y) chromosomes. I wonder if that's really so, or whether just the visible/easily detected differences are.

To add the excitement, some genes express differently depending on whether they were inherited from the male or the female parent, which could in theory result in offspring being 'purebred' in phenotype, even though they were crossbreds, genetically.

I've found, over the years, that just about any 'fantastic' interbreeding/crossbreeding effect can be justified genetically if you dig deep enough. Whether outlandish interactions are at all likely is a whole other matter, of course.