species differences

C

Carnuth

i dont
Registered Senior Member
are asians and hispanics and caucasians and africans different species? Like the difference between a golden retriever and labrador? they are different species correct? and if that is correct and they can interbreed, are humans the same? so back to the first question.

I dont know if thats a stupid question, but what the hell, if im wrong at least ill know =)
 
No, we are all homo sapiens. Of course, there are different strains and variations. No two humans are identical. Populations that are isolated eventually become more alike eachother (I'm sure you know this.) After long enough, speciation occurs and a new species is formed.

Almost all dogs can interbreed. Even some which are different species - even though the offspring may end up sterile. Apparantly humans used to do exactly this with neanderthals.

Lastly..if you breed two variations, you'll end up with an outbread mutt. Since those are usually heterozygous for traits at the loci, they will exhibit something called 'hybrid vigor'. And these hybrids will exhibit some strong qualities. Although great traits isolated in a lineage may be lost. outbreeding is very important to maintaining the genetic diversity and vitality of the species.
 
Originally posted by Elbaz
Almost all dogs can interbreed. Even some which are different species.
Click to expand...
The definition of 'species' which I was brought up with (University of Southampton) indicated that members of one species had to be reproductively isolated from another. That is to say cannot reproduce with another species.

Here is a link which supports this definition. (I couldn'y find the one I was looking for, so it may have a lot of off topic content).

Admittedly, the rule gets hazy if two groups can produce sterile offspring (e.g. Horses and Donkeys).
-----------
I'd say Asians, Negroes, Hispanics etc. are just different breeds of homo sapiens. But that is only my opinion.
 
Yeah, basically a species is anything that can produce reproductively viable offspring amongst themselves. The definition doesn't really have anything to do with other species, rather a population sharing a gene pool. Reason is because there isn't a thin enough threshold to measure species by. Genetic drift will occurs as species fill in a niche. And after long enough, they become so distinct that reproduction amongst other related species doesn't really work. It's always possible - like a human, theoretically, could produce offspring with a cat...but that's like 1 in 10 billion... Maybe a trillion. I don't know.

An example I tried:
Lycopersicon Pimpenifolium (very closely related) can interbreed with lycopersicon esculentum - the common tomato. Again, I've tried this myself. I believe the seeds are viable.

And then theres my favourite...
Lion x Tiger = liger (sterile)
I've never made any of those :rolleyes:
 
You enjoy gardening? That's something I'll probably do when I get old.

I'm not absolutely certain, but I think genetic drift is something to do with small populations; gene frequency not always being passed on as stats would predict.

Yeah, a human and a cat would not be very likely as you suggest. I think they have a different number of chromosomes for a start! The probability for the mutation needed to come about is comparable to the probability for two humans to conceive a kitten by themselves!
 
Not really...I tried it once as an experiment to see if I could actually hybridize something. It worked - and as I learnt, happens quite regularly in the world of tomatoes.

As for the bio, I'm a bit rusty on my definitions too, so I couldn't really argue much about the details. What's certain obvious is that I would not want a cat hybrid for a child :bugeye:

oh, and apparantly the aliens are hybridizing us. So with the right technology it probably wouldn't be too hard.. Just add prosthetic chromosomes or something and you could breed with almost any animal on the planet..
 
Last edited:
Originally posted by Elbaz
Not really...I tried it once as an experiment to see if I could actually hybridize something. It worked - and as I learnt, happens quite regularly in the world of tomatoes.

As for the bio, I'm a bit rusty on my definitions too, so I couldn't really argue much about the details. What's certain obvious is that I would not want a cat hybrid for a child :bugeye:

oh, and apparantly the aliens are hybridizing us. So with the right technology it probably wouldn't be too hard.. Just add prosthetic chromosomes or something and you could breed with almost any animal on the planet..
Click to expand...

Whats the 'not really' part critising?

Anyway, prosthetic chromosomes? There are so many things that have to work together, creatures that are not very closely related cannot be crossbred. Their different chemistries would terminate the foetus at a very early stage of development.

Plants are different as many are extremely closely related. Lettuce, cabbage, brussel sproust and the likes were all once the same plant (humans selectively bred them) and as such it is these types that are easiest (Tomatos etc.) to crossbreed.
 
I was going to do a science fair thing on the crossbreeding..but alas - it sucked.

I do not 'enjoy' gardening ;)

Anyways, I read about these 'prosthetic' chromosomes. Yeah, it's a bit far fetched considering the way things work in reality, but sounds workable. You wouldn't want a human-animal hybrid anyways, but you have to wonder the possibilities.

On the cross-breeding point, mutations and crossbreeding are supposed to be great (in terms of survival) for all plant species. In animals, the results are almost always undesirable. Usually to do with mobility.
 
There is confusion to the strength of the term 'race' here. A 'race' is effectively a subspecies, which means that all humans are the same species. This is shown by successful interbreeding between the different races (I hate racial separation in society, personally). Succussful breeding of course meaning the production of viable offspring.

In short, Elbaz was right, we are all Homo sapiens.
 
And all domestic dogs are the same species also.
I can see why you assumed otherwise considering the physical differences.
But these are both members of the same species;
neopolit.jpg

amberly-chihuahua.jpg
 
Not true..

There are generally many species of the cannine genus. Some very closely related. Dogs tend to belong to the same species, but not always. Especially some of the more exotic ones. I guess it all comes down to your definition. I consider the 'dingo' a dog, as well as many other wild animals. Although even they can interbreed with the average dog. Some of they may as well even be subspecies.
 
hm well normally dr lou is right, but if thats the case shouldnt there be something more specific that just "species or subspecies" or is that not PC? ;)
 
It can't really be quantified as we'd like it. We are all made of the same nucleotides, same chemicals and what not. And when it comes down to it, classifications are nothing more than superficial interpretations.

They're still debating on whether to include the sixth kingdom or not. By that logic they could easily fit in a seventh or an eigth. And eventually we'd have as many dimensions as the string theory. Inefficient - yes - but it's all we got :mad:
 
You must log in or register to reply here.
Back
Top