|
|
Silver Dragon Breath dragon forums
| View previous topic :: View next topic |
| Author |
Message |
Ragnarok
Global Moderator
Joined: 27 Sep 2004
Posts: 1091
Location: Tucson, AZ, USA.
|
 Posted: Wed 23 Jul 2008 20:26 Post subject: |
 |
|
| Draquenvar wrote: |
| I've read about some genetically engineered "chimeras" (in this case referring to a human/animal hybrid). However, this type of activity is probably considered illegal in most locations of the world, |
On the contrary, it's legal in most places; or rather, I can't think of anywhere that has actually outlawed it. I know the UK tried to pass a ban a while back, but that failed rather spectacularly.
| Quote: |
| (If I recall correctly, ligers and tigons are not fertile - correct me if I'm wrong) |
Apparently, female ligers and tigons are fertile.
| Quote: |
| But as far as genetic engineering goes, I would certainly not turn down the idea that a hybrid or genetically altered species can be created. But it probably wouldn't ever be done in anything more than secret, since so many disagree with it. |
Off the top of my head, I can think of the glowfish and glowing mice, and the former are being marketed as pets. Not to mention all the GMO plants and other organisms that are being produced.
ETA: Forgot about the geep.
_________________
To win against an opponent stronger than yourself, you must not be weaker than that opponent. - Takamachi Nanoha
Last edited by Ragnarok on Thu 24 Jul 2008 9:47; edited 1 time in total |
|
| Back to top |
|
 |
Rayadragon
Shining Dragonstar
Joined: 28 Oct 2003
Posts: 264
Location: Somewhere between reality and imagination
|
| Posted: Thu 24 Jul 2008 6:27 Post subject: |
|
|
| Quote: |
| Apparently, female ligers and tigons are fertile. |
Learn something new everyday. I wish they had a reference of some sort though.
| Quote: |
| Off the top of my head, I can think of the glowfish and glowing mice, and the former are being marketed as pets. Not to mention all the GMO plants and other organisms that are being produced |
I hadn't been thinking in terms of this. If you're talking about just genetically altering something to make a transgenic animal/plant/etc. with a single additional gene or mutation, then this is done on a fairly regular basis and is published incessently. It's the backbone of a lot of genetics experiements, because it's hard to make the point of relevancy of a technique unless you can show some data in mice (or some other model organism). Some diseases are hard to model in mice, so there's always new ones being published trying to show why this one is better than all the other versions that are out there.
_________________
"People who are easily offended need to be offended more often."
"Do on to others as you would have others do on to you." |
|
| Back to top |
|
|
Hyraxylos
Shining Dragonstar
Joined: 13 Jun 2007
Posts: 805
Location: Atlanta, GA
|
| Posted: Thu 24 Jul 2008 9:43 Post subject: |
|
|
| Ragnarok wrote: |
| Apparently, female ligers and tigons are fertile. |
So lions and tigers are actually the exact same species then? Wow... 
_________________
The statement below this one is false.
The statement above this one is true.
This statement is false. |
|
| Back to top |
|
|
Ragnarok
Global Moderator
Joined: 27 Sep 2004
Posts: 1091
Location: Tucson, AZ, USA.
|
| Posted: Thu 24 Jul 2008 10:05 Post subject: |
|
|
| Rayadragon wrote: |
| Quote: |
| Apparently, female ligers and tigons are fertile. |
Learn something new everyday. I wish they had a reference of some sort though. |
Does this help?
| Quote: |
| According to Wild Cats Of The World (1975) by Guggisberg, ligers and tigons were long thought to be sterile: In 1943, however, a fifteen year old hybrid between a lion and an 'Island' tiger was successfully mated with a lion at the Munich Hellabrunn Zoo. The female cub, even though very delicate, was raised to adulthood. |
Since it's identical to what's in the wiki article, I suspect that it's the source, and it doesn't mention that they're "often fertile", though even one example shows that they can be.
| Hyraxylos wrote: |
| Ragnarok wrote: |
| Apparently, female ligers and tigons are fertile. |
So lions and tigers are actually the exact same species then? Wow... |
No, because the liger is unable to mate with one of its own kind to propagate the hybrid species.
_________________
To win against an opponent stronger than yourself, you must not be weaker than that opponent. - Takamachi Nanoha |
|
| Back to top |
|
|
Rayadragon
Shining Dragonstar
Joined: 28 Oct 2003
Posts: 264
Location: Somewhere between reality and imagination
|
| Posted: Thu 24 Jul 2008 10:31 Post subject: |
|
|
Yeah, not much by my book. It's the exact same as the Wiki reference, and there's no original citation with that comment.
Thinking on the tiger/lion/liger/same species line, there's an obvious reference we haven't mentioned yet. Wolves and domesticated dogs are considered separate species, yet can interbred and I believe produce fertile offspring.
From the chromosomal standpoint, I'd wonder if wolves/dogs have the same number of chromosomes and if lions/tigers do not. The chromosome number discrepancy and gene location issues are pretty big for reproduction. It's hard to make reproductive cells if there's large differences in those, but small differences are better (thought still not well) tolerated and would result in hybrids that have higher fertility and reproductive capabilities.
_________________
"People who are easily offended need to be offended more often."
"Do on to others as you would have others do on to you." |
|
| Back to top |
|
|
Hyraxylos
Shining Dragonstar
Joined: 13 Jun 2007
Posts: 805
Location: Atlanta, GA
|
| Posted: Sat 02 Aug 2008 14:39 Post subject: |
|
|
Time out. 
Ragnarok, I'm getting confused. I was taught that the line that separates one species from another was whether they could produce fertile offspring and now apparently that isn't it. Could you please explain to me what the definition is of a "species"? Because it looks like you're contradicting yourself here, saying first that ligers CAN procreate, and then that they CAN'T procreate. Which is it? 1 of 3 choices:
1. Ligers can breed, therefore tigers and lions are merely two different races of the same species.
2. Ligers cannot breed, therefore tigers and lions are different cats altogether.
3. I am mistaken about what does or does not separate one species from another. Please clarify if this is the case.
_________________
The statement below this one is false.
The statement above this one is true.
This statement is false. |
|
| Back to top |
|
|
DarkDragon
Administrator
Joined: 16 Apr 2004
Posts: 1575
|
| Posted: Sat 02 Aug 2008 16:47 Post subject: |
|
|
| Hyraxylos wrote: |
Time out.
Ragnarok, I'm getting confused. I was taught that the line that separates one species from another was whether they could produce fertile offspring and now apparently that isn't it. Could you please explain to me what the definition is of a "species"? Because it looks like you're contradicting yourself here, saying first that ligers CAN procreate, and then that they CAN'T procreate. Which is it? 1 of 3 choices:
1. Ligers can breed, therefore tigers and lions are merely two different races of the same species.
2. Ligers cannot breed, therefore tigers and lions are different cats altogether.
3. I am mistaken about what does or does not separate one species from another. Please clarify if this is the case. |
This is a rather more complicated thing than that. So let me make some points to either further your confusion or clear some things up
1. Tigers and Lions are two seperate species that have the remarkable ability to intermingle and create offspring, known as Ligers/Tigons.
2. A liger/tigon is usually sterile, such as the Mule, the offspring between a horse and a donkey.
3. There have however, been cases where a Liger/Tigon is fertile, and I do myself remember that one femal tigon gave birth to a healthy baby tiger cub. (Yes, Tiger cub. The Father was a tiger, and genetic testing showed it as a tiger)
So, in retrospect, interbreeding is possible with two closely related species, however it is rare, and offspring are usually sterile or have a variety of health problems, usually leading to death.
_________________
May you be in heaven a half hour before the devil knows you're dead.
-An Irish toast |
|
| Back to top |
|
|
Rayadragon
Shining Dragonstar
Joined: 28 Oct 2003
Posts: 264
Location: Somewhere between reality and imagination
|
| Posted: Sat 02 Aug 2008 16:54 Post subject: |
|
|
I'm not Ragnarok but I can clarify the point somewhat.
| Quote: |
| 3. I am mistaken about what does or does not separate one species from another. Please clarify if this is the case. |
For the most part animals of separate species can't interbreed and produce fertile offspring, but that isn't the only determinante of what separates a species. It's just the easiest and most common way to make a distinction.
| Quote: |
1. Ligers can breed, therefore tigers and lions are merely two different races of the same species.
2. Ligers cannot breed, therefore tigers and lions are different cats altogether. |
You're missing the point of why tigers and lions are the same species: Ligers CANNOT mate with other Ligers and produce offspring. If ligers can't produce viable offspring with other ligers, then they can't be concidered a species, and the liger's parents can't be concidered the same species either, or else their offspring would all be able to produce viable offspring with each other.
_________________
"People who are easily offended need to be offended more often."
"Do on to others as you would have others do on to you." |
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
|
