1) You won't be that substantially different from your parents. That level of change doesn't happen in a single generation. Plus, if you can interbreed with other humans, you'd still be the same species, just with variations. Contrary to popular opinion, red heads are the same species as everyone else...
3 eyed people are still human, as are
12 toed people.
2) The definition of a species isn't exact as it exist as both a scientific term for geneticists and a taxonomic term for biologists.
http://en.wikipedia.org/wiki/Species_problem. I'm using the standard biological definition applied to higher level organisms.
You're implying that a new species is only born out of cross-breeding between two different - but sexually compatible - species. That's not how it works with the evolution theory.
No I'm not. The creation of a new species from its precursors is an ongoing process of genetic change across thousands of generations. Two biologically compatible creatures of the same species give rise to progeny of the same species with whatever variations. You never get a new species from a single generation of sexual (or asexual) reproduction.
There are peculiar hybrids but these aren't, by and large, stable genetic species and are the product of unnatural interactions between species that wouldn't find themselves in a position to mate without human intervention. Too much genetic diversity between parents leads to faulty offspring even if conception is bioloigcally possible. Even between very similar creatures of the same genus (taxonomy), the offspring are non-viable or sterile creating an evolutionary dead-end. Hence, a new species from two parents is basically impossible, because you can't get that much diversity and still have a stable new lifeform. And this is perhaps the problem, because we think of a species as a distinctly different creature, yet it's more a degree of compatibility.
Ergo, if you have a chicken born from an egg, it's parents were chickens. And their parents were chickens. And their parents were chickens. Going back and back, each generation slightly different. If you sample the chicken from 1,000,000 years earlier, you may have a species that is biologically incompatible with present-day chickens. That's an easy distinction to make. Quite where one species ends and a new one begins from it is hard to say. The only certainty is that, as I've said, every parent produces progeny of the same species, and every offspring comes from the same species. The creature that laid the chicken egg was a chicken. The first eggs came from species that weren't chickens.
Now you could trace back every generation to find the first generation that isn't biologically compatible with the current chicken, and conclude that marks the end of that species and its offspring, the first to be biologically compatible with the contemporary species, to be the first chicken. Then you'd have your argument, the egg came before the chicken. However, what you'll likely find (and this is of course impossible to scientifically test because we can't try mating thousand year old species with current species, but interactions between higher-level genetic variances certainly points to this) is that older generations of the current species would have varying compatibility, with offspring of different health and sexual viability. There won't be a nice distinction between species like there is consoles. The notion of species becomes one of human perception of an infinite genetic diversity, hampered by legacy thought processes constrained by a language of naivity built around the high-level perceptions of the people who created that language. Which is what leads to the notion of a species being defined as reproductively isolated, which offspring aren't.
