1st i asked why human races arent considered different species because every race is physically different (ie: skin and hair types, immunities, black people dominating sports)and someone said its because we can still interbreed. so i asked how a lion and tiger can breed but at the same time are different species. people responded that tigers and lions dont breed naturally because they are from different continents. But check out what i found from wikipedia:
"Another area where the ranges of Asiatic Lions and Bengal Tigers overlap is in the Gir Forest in India; however, this combination of species in the wild is considered highly unlikely."
This implies thatt intances where ligers apeared naturally have occured. Yet theres no way a lion and tiger will ever be the same species. So this scratches out the possibility that human races are 1 species because we can interbreed.Plus, different races wouldnt interbreed if we didnt have transportation like airplanes or ships. im so confused
How do you explain a liger part 2?
Again (as stated by mareeclara and myself in the other answer) ... being able to "interbreed" to produce offspring is not enough if those offspring are themselves unable to continue the species.
We then call those offspring "hybrids". They are genetic dead-ends.
So if hybrids between two species are themselves infertile *OR* are unable to breed with other hybrids ... then we're not talking about one big, successully breeding species, but about two separate species.
Male ligers (and tigons, the cross between a male tiger and female lion) are sterile.
Therefore ligers and tigons are unable to breed with each other. They are unable to continue the species. They are hybrids ... genetic dead-ends.
Therefore lions and tigers are as separate a species as horses and donkeys, which are also able to interbreed to produce offspring (mules) but those offspring are unable to continue the species.
The non-overlapping geography is not the definition of separate species. Differentiation can *cause* the speciation (the separation of one species into two) ... IF they are separated for enough time. But that's not the *definition* of separate species.
That's exactly why human ethnic groups are not separate *species*. Even though they have been isolated geographically, this has not been for a long enough time for them to lose the ability to produce *FERTILE* offspring. All ethnic groups of humans can produce fully *FERTILE* offpring with all other ethnic groups ... offpring who are themselves able to do the same with other like offspring. Thus, those offpring are not considered "hybrids", but are all of the same species.
How do you explain a liger part 2?
There are a whole range of what we call isolating mechanisms that stop interbreeding between different species.
There are pre-zygotic and post-zygotic isolating mechanisms ( before and after the zygote has been formed)......more interbreeding occurs in plants, but its quite rare in animals and in most cases its due to humans forcing or introducing species to each other that would not normally occur together.
Some of these isolating mechanisms ( in animals here in particular) are things like being separated by space, having particular mating and bahavoural rituals, being fertile at the wrong time, not physcially having reproductive parts that fit, having chemicals that kill sperm before it reaches the egg, the egg not recognising the sperm, and then after the sperm has entered the egg forming a zygote there maynot be the right chromosome number so not dividing, not having all the right "stuff" so feutus not able to develop, offspring dying soon after birth, offspring dies at some other premature time, offspring not fertile, the next generation are not fertile.
There are MANY MANY things that stop hybrids being formed...as I said more so in animals than plants ( as plants don;t have bevahoural issues to deal with).
In a way you are right in saying without transport we would not necessarily breed with other people from other places.
THe barriers in humans is even more complex than other animals as we have different languages ( so can't communicate) and religious issues which tend to stop people from being together more so than travel etc.
A species is that that interbreeds with each other and produces fertile offspring...as the liger is infertile, the tiger and lion are not the same species. I do not accept that ligers would occur natuarally.....they are exceedingly rare in zoo's and it would have to be under extremely extraordinary circumstances for them to occur naturally.....even if they did so, because they are not fertile.
I still can't quite get my head around what you are asking.....hybrids occur.....in animals its almost always due to human intervention ( species that have been separated by space for a period of time are known to interbreed and produce offspring.....thats because they don;t live together and don;t need to put up reproductive barriers to stop that particular species interbreeding ( as they are not there with each other).....but that has nothing to do with humans.....like other species there are many populations of humans, which have been isolated...but not for any great length of time ( only a few thousand years)....this has caused some features to be different....which we call races, but there are other regional differences as well. Apart from these and the language, culture ( in some places) and relgious affiliations.....the latter 3all considered behavoural...there is not enough difference between us all to consider us different species...we call all interbreed and produce fertile offspring@!!!!
How do you explain a liger part 2?
Yours case is like "The mind believes what it likes to believe" (anyways dnt mind....no offence intended)
If those technologies wnt have build then the races would never interbreeded but still they had the potential!
But u are thinking the correct way...lets think of a hypothetical situatuin where these technologies were not built....then with increasing time the different races would accumulate even more genetic differences and thus slowly they wud lose the potential of interbreeding....then speciation would be complete and then ur dream wud be true!
So, these technologies act like bridges between diff. races and does not let them to be diff. species...u understood or not?
Do reply back...i sort a like u
How do you explain a liger part 2?
the difference is that the offspring of 2 humans of different race or ethnicity will still be fertile and capable of breeding with other humans..
whereas the liger is infertile.. it's a dead-end product.. just like the mule.
How do you explain a liger part 2?
I see your point very good point by the way,I agree with you,I read your other question too.
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