# Species concepts and hybridization



## GeoTerraTestudo (Jul 8, 2012)

Because there has been so much discussion lately about species and hybrids, I thought I would start a thread in which we can these topics the attention they deserve. So now, I am going to start by defining each of these terms, and explaining their significance.

*1) Species*
As the lowest standard unit in taxonomy, species represents a fundamental unit in biology. This term may be defined in various ways, but two of the most common are the biological/reproductive species concept, and the phylogenetic/cladistic species concept.

A. Biological/reproductive species concept - This is an old but very useful definition of species. Simply put, animals in the same species are those that can successfully reproduce with each other, in other words, those that can produce offspring that are both viable (health) and fertile (capable of reproducing themselves). One qualifier given may be that only animals that would reproduce under their own initiative (without human intervention) may be considered members of the same species.

B. Phylogenetic/cladistic species concept - In this somewhat newer approach, animals may be considered as members of the same species if their genetic makeup is more similar than a given threshold (often originally based on the biological species concept). One standard often used is 97% similarity in RNA genes. Other genes may call for different levels of similarity.

*2) Hybridization*
The word "hybrid" may come from the Old English "hy" (half) and "brid" (breed), or literally "half-breed," meaning an individual whose lineage is half one type, half another. The world "hybrid" can technically refer to any taxonomic level, whether within a species (intraspecific) or between species (interspecific). In fact, at the molecular level, we can even speak of DNA hybridization, which is simply allowing two different strands of DNA to bond together. We could also say that two wild animals from different subspecies can hybridize, or that two people from different races can hybridize, or that two domestic animals from different breeds can hybridize. However, we usually refer to such crosses as mixes or intergrades, because the offspring are essentially at no risk of defects. Usually when we use the term "hybrid," we are referring to interspecific hybridization, or the crossing of animals from different species. This is controversial because such animals usually cross under human influence, and the offspring often have reduced viability or fertility.

*3) Taxonomy*
The next taxonomic level above species is "genus." Congeneric animals have many similarities and share a common ancestor, but have diverged to a significant degree, and no longer usually mate. If they do, the offspring may have defects. The level above genus is "family." Confamilial animals are broadly similar, but usually don't mate, and if they do, the offspring are unlikely to survive. The next level up is "order." Animals in the same order are only distantly related, and completely incapable of hybridizing.

*4) Genetics*
Genes are DNA sequences that code for proteins, which build and operate our bodies. The location of a gene on DNA is known as a locus. DNA is usually strung together in long molecules, which are tightly coiled into structures called chromosomes during replication. The number of chromosomes is a defining characteristic of a species. When two animals from the same species mate (whether or not they are from the same subspecies, race, or breed), basically all the genes line up, resulting in healthy, normal offspring. If two animals from different species but the same genus mate, not all of the genes line up. Therefore, the resulting offspring might not survive, or if they do, their gonads (testes or ovaries) may be unable to produce sperm or eggs. If two animal from different genera but the same family mate, the offspring may die in the egg or uterus, or if it hatches or is born, it may die as an infant.

In birds and mammals, interspecific hybrids of both sexes may be sterile. However, the heterogametic sex is sterile more often than the homogametic sex. This means that, the sex with two different types of sex chromosome is more likely to be sterile than the one with two of the same sex chromosome. In mammals, males are heterogametic (XY) while females are homogametic (XX). In birds, females are heterogametic (ZW) and males are homogametic (ZZ). This phenomenon is known as Haldane's Rule. It probably exists because the homogametic sex has a "backup" copy of every gene, while the heterogametic sex does not.

Most reptiles have temperature-dependent sex determination (TSD), with no heterogametic sex. In that case, interspecific hybrids could be more likely to be viable and fertile than in birds or mammals.

*5) Ethics*
So knowing all this, the question remains, "Should we or should we not hybridize animals in captivity?" I would argue that no, we should not hybridze animals, and here's why.

A. Conservation - If you think of the pet hobby as a kind of collective "Noah's Ark" project, then it is our responsibility to keep our animal stocks pure, so that if reintroduction is necessary, captive animals could be used.

B. Behavior - Hybrid animals often have conflicting impulses, because each of their parent species (or even subspecies) exhibits different behaviors. For the sake of the animal, it is better to prevent such inner conflicts from arising.

C. Health - As mentioned above, interspecific hybrids may have compromised health or fertility. For the sake of medical and reproductive health, it is best to allow animals to breed with their own species (and even subspecies).


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## EricIvins (Jul 8, 2012)

GeoTerraTestudo said:


> Because there has been so much discussion lately about species and hybrids, I thought I would start a thread in which we can these topics the attention they deserve. So now, I am going to start by defining each of these terms, and explaining their significance.
> 
> *1) Species*
> As the lowest standard unit in taxonomy, species represents a fundamental unit in biology. This term may be defined in various ways, but two of the most common are the biological/reproductive species concept, and the phylogenetic/cladistic species concept.
> ...



The Pet Trade is NOT, and will NEVER be a "Noahs Ark".......

There are people with assurance colonies, and people with "Pets".......Two very different situations, with two very different goals.......

I'd also like to see an instance of compromised health or Fertility in a REPTILE......Not a mammal......


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## GeoTerraTestudo (Jul 8, 2012)

EricIvins said:


> The Pet Trade is NOT, and will NEVER be a "Noahs Ark".......



It better be, seeing as how there are 7 billion people on Earth, and counting. Other species are running out of room, and if we don't take their fate into our hands, we may regret it someday.



> I'd also like to see an instance of compromised health or Fertility in a REPTILE......Not a mammal......



Intergeneric hybrid Galapagos iguanas (_Amblyrhynchus_ x _Conolophus_) appear to be sterile:

http://web.archive.org/web/20070606...tion.org/files/species/pdf/land-iguana-en.pdf
http://books.google.com/books?id=3l...jgK#v=onepage&q=hybrid iguana sterile&f=false


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## EricIvins (Jul 8, 2012)

GeoTerraTestudo said:


> EricIvins said:
> 
> 
> > The Pet Trade is NOT, and will NEVER be a "Noahs Ark".......
> ...



It NEVER will be......7 billion people or not......The Pet trade is about animal companions, not preserving species.......That is the job of people who set up assurance colonies.......

"Breeders" can do both - Some focus on one aspect more than others - Hoewever, most private individuals, no matter how hard they try will never be a part of species repatriation.......

The world is full of Hybrids, and they are bred for whatever reason......When it comes to "Pet" trade animals, it doesn't matter if the animal is a hybrid or not - It is meant as a companion, and that is as far as it goes........A "Breeder" shouldn't be looking for parental stock in the Pet trade to begin with.......Those are people to avoid, no matter what they are breeding......


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## GeoTerraTestudo (Jul 8, 2012)

EricIvins said:


> It NEVER will be......7 billion people or not......The Pet trade is about animal companions, not preserving species.......That is the job of people who set up assurance colonies.......
> 
> "Breeders" can do both - Some focus on one aspect more than others - Hoewever, most private individuals, no matter how hard they try will never be a part of species repatriation.......
> 
> The world is full of Hybrids, and they are bred for whatever reason......When it comes to "Pet" trade animals, it doesn't matter if the animal is a hybrid or not - It is meant as a companion, and that is as far as it goes........A "Breeder" shouldn't be looking for parental stock in the Pet trade to begin with.......Those are people to avoid, no matter what they are breeding......



I think conservation trumps purism, so even "mutt" lines can still be repatriated if need be. Intraspecific mixing may be undesirable, but it is not necessarily the end of the line. However, interspecific hybridization usually is.

Anyway, even if all you wrote above were true (and I'm not convinced that it is), how does that justify interspecific hybridization in captivity?


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## EricIvins (Jul 8, 2012)

GeoTerraTestudo said:


> EricIvins said:
> 
> 
> > It NEVER will be......7 billion people or not......The Pet trade is about animal companions, not preserving species.......That is the job of people who set up assurance colonies.......
> ...



No they can't be. The guidelines for repatriation already exclude 98% of private keepers. You have to have some serious crudentials to even be considered for such, not to mention the politics and red tape involved.......

How do you justify keeping animals in captivity to begin with?


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## GeoTerraTestudo (Jul 8, 2012)

EricIvins said:


> No they can't be. The guidelines for repatriation already exclude 98% of private keepers. You have to have some serious crudentials to even be considered for such, not to mention the politics and red tape involved.......



I think this is a very narrow view of repatriation. Sure, under present conditions, it may not be advisable. But the whole point of a Noah's Ark is to save some for a Rainy Day. Today's unqualified keeper could become tomorrow's wildlife restorer.



> How do you justify keeping animals in captivity to begin with?



1) Biophilia (humanity's affection for other living beings)
2) Conservation potential (see above)

But you still haven't answered my question: how do you justify interspecific hybridization?


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## EricIvins (Jul 8, 2012)

GeoTerraTestudo said:


> EricIvins said:
> 
> 
> > No they can't be. The guidelines for repatriation already exclude 98% of private keepers. You have to have some serious crudentials to even be considered for such, not to mention the politics and red tape involved.......
> ...



It isn't a narrow view. It is personal experience......Todays unqualified keeper will stay unqualified tommorrow unless he/she becomes AZA accredited......Don't beleive me? Do the research......

There are a few private programs that deal with repatriation using non AZA accredited facilities, but they are in the vast minority, and again, 98% of private individuals are unqualified to release animals to those programs to begin with........


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## GeoTerraTestudo (Jul 8, 2012)

EricIvins said:


> It isn't a narrow view. It is personal experience......Todays unqualified keeper will stay unqualified tommorrow unless he/she becomes AZA accredited......Don't beleive me? Do the research......
> 
> There are a few private programs that deal with repatriation using non AZA accredited facilities, but they are in the vast minority, and again, 98% of private individuals are unqualified to release animals to those programs to begin with........



Be that as it may, why does that make it okay to hybridize animals in captivity?


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## StudentoftheReptile (Jul 9, 2012)

Very interesting thread. Thanks to GTT for starting it.

First off, I kinda have to agree with Eric in that there is a clear separation between exotic animal keepers in general: there are "pet owners" and there are those dedicated to assurance colonies for the purpose of conservation. There are a few exceptions where individuals fall under both labels, but I would say the vast majority of that 7 billion+ demographic are, at the core, pet owners seeking animal companionship and/or feeding their biophilia. Its not necessarily a judgment, just a reality.

On the flipside, as far as repatriation, and the "Noah's Ark" scenario, I do think more should be aware of these types of issues and the industry as a whole should put more effort into preserving the more obscure species in captivity.

Personally though, I could give a flying rat's arse what the AZA thinks. Private keepers are just as capable of maintaining and propagating rare species in captivity; their only problem is that money often gets in the way. But in short, if a rare herp species was on the line, and some captive breeding needed to be done, I'd trust any number of private keepers than I would an AZA-accredited organization.


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## GeoTerraTestudo (Jul 9, 2012)

StudentoftheReptile said:


> Personally though, I could give a flying rat's arse what the AZA thinks. Private keepers are just as capable of maintaining and propagating rare species in captivity; their only problem is that money often gets in the way. But in short, if a rare herp species was on the line, and some captive breeding needed to be done, I'd trust any number of private keepers than I would an AZA-accredited organization.



Thank you. My point exactly.


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## StudentoftheReptile (Jul 9, 2012)

GeoTerraTestudo said:


> StudentoftheReptile said:
> 
> 
> > Personally though, I could give a flying rat's arse what the AZA thinks. Private keepers are just as capable of maintaining and propagating rare species in captivity; their only problem is that money often gets in the way. But in short, if a rare herp species was on the line, and some captive breeding needed to be done, I'd trust any number of private keepers than I would an AZA-accredited organization.
> ...



Yeah, I mean...I admit, the reptile industry is far from perfect, and certainly has faults....but when someone is dedicated to a particular species, they will get some stuff done!

AZA-accredited zoos will tie themselves for years with red tape and paperwork just to pair up two animals, and the private sector will be at least a few years ahead. Now I understand the importance of pure bloodlines and lineage, etc., but again, private keepers are just as capable of handling this.

Honestly, when push comes to shove, the zoos will start looking to private keepers for advice and for stock. And in some cases, they already do.
----

On a slightly different note, I want to preface my following statements with something my late grandfather said: "In a 100 years from now, no one will know the difference." Now, some may take a little offense to that in matters like this, but let's look at the big picture here. The planet as a whole is spiraling downward in an irreversible path all across the board: economically, politically, and environmentally. We're so worried about this Noah's Ark scenario, but seriously, at the rate we're decimating entire ecosystems, flattening forests, bull-dozing grasslands, polluting waterways, etc....how imperative is it that we have every single subspecies of say, leopard tortoise? Heck, 50 yrs from now, I'd be happy just to still be able to get a leopard tortoise period if I wanted one! I know a lot of this could be doomsday speculation, but there could honestly come the day where there will be more of a said species in captivity, then there is in the wild. Heck, with some species, this is already the case.

I used to get really worked up about hybrids and pure bloodlines, etc...but not so much anymore. There are already people who devote the necessary attention to these "assurance colonies." Yeah, it'd be nice if more people thought that way, but I'm not as worried about it as I used to be. In the end, its not fair for me to judge or criticize what people do with their animals, as long as the animals are taken care of, represented properly, and there are no health issues involved with said hybridization. Again, in 100 yrs, how much of this is really going to matter? In my opinion, we'll have a lot more to concern ourselves with the decades to come.


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## Madkins007 (Jul 9, 2012)

Private keepers, in the worlds of reptiles, fish, dogs, etc., have both done wondrous things, and performed atrocities in their fields. They have 'broken' the secrets to keeping or breeding rare or difficult species far more often than zoos or similar facilities have, but they have also done lots of less praiseworthy things- usually either in the pursuit of a buck or out of ignorance.

I'm willing to take the good with the bad overall since it is just the way things are. 

As for moral justification to hybridize... I am not a fan of it, but hydrids often help drive interest in a species (or cross). This helps drive better research into the species and makes the species valuable enough that it gets more respect and better overall cares. 

Look at ball pythons. I do not like the vast majority of the color morphs, but all of that focus has really brought out a lot of good info on cares for the species, as well as driving the prices of 'plain' animals down. (I know color morphs are not the same thing as interspecies hybrids, but the overall lesson, I believe, is about the same.)

We may well live to see a hybrid tortoise species that can do well in a larger portion of the US without having to be indoors at all- something medium-small and easy to care for. Most likely based on the Russian. Overall, this is something I think many of us would support purposeful hybrids like this- much like breeding a dog to be a better pet for an apartment dweller. 

We may see hybrids of the more colorful species to create a whole palette of colors. I know a lot of keepers would love to see this, and a lot of us more 'purist' types will be appalled. However, it would also probably drive a lot o interesting research in breeding, etc. while also pushing the costs of the 'plain' animals down again.


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## StudentoftheReptile (Jul 9, 2012)

Madkins007 said:


> As for moral justification to hybridize... I am not a fan of it, but hydrids often help drive interest in a species (or cross). This helps drive better research into the species and makes the species valuable enough that it gets more respect and better overall cares.
> -------------
> We may see hybrids of the more colorful species to create a whole palette of colors. I know a lot of keepers would love to see this, and a lot of us more 'purist' types will be appalled. However, it would also probably drive a lot o interesting research in breeding, etc. while also pushing the costs of the 'plain' animals down again.



Good points. I think it has a more positive effect than people think; whenever a controversial hybrid pops up in the scene, it often stimulates more hobbyists to focus on pure bloodlines as well. After all, in many cases, when responsible keepers wish to create a hybrid, they want pure parents to start with, because they want to have as much knowledge and control into what goes into the mix, ya know? And then on the other side of the fence, there's those who are "freaked out" by the crossing and want to devote more efforts into preserving the pure lines.

So all in all, a hybrid certainly isn't as catastrophic of an event as some people make it out to be.


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## GeoTerraTestudo (Jul 9, 2012)

StudentoftheReptile said:


> On a slightly different note, I want to preface my following statements with something my late grandfather said: "In a 100 years from now, no one will know the difference." Now, some may take a little offense to that in matters like this, but let's look at the big picture here. The planet as a whole is spiraling downward in an irreversible path all across the board: economically, politically, and environmentally. We're so worried about this Noah's Ark scenario, but seriously, at the rate we're decimating entire ecosystems, flattening forests, bull-dozing grasslands, polluting waterways, etc....how imperative is it that we have every single subspecies of say, leopard tortoise? Heck, 50 yrs from now, I'd be happy just to still be able to get a leopard tortoise period if I wanted one! I know a lot of this could be doomsday speculation, but there could honestly come the day where there will be more of a said species in captivity, then there is in the wild. Heck, with some species, this is already the case.
> 
> I used to get really worked up about hybrids and pure bloodlines, etc...but not so much anymore. There are already people who devote the necessary attention to these "assurance colonies." Yeah, it'd be nice if more people thought that way, but I'm not as worried about it as I used to be. In the end, its not fair for me to judge or criticize what people do with their animals, as long as the animals are taken care of, represented properly, and there are no health issues involved with said hybridization. Again, in 100 yrs, how much of this is really going to matter? In my opinion, we'll have a lot more to concern ourselves with the decades to come.



Agreed. As I mentioned above, what I'm really concerned about is interspecific hybridization (different species and different genera). Subspecies mixing should be avoided, but if survival is at stake, it's better to allow it than to let a species become inbred or extinct. Zones of intergradation may exist in nature anyway. If reintroduced into the wild, depending on the animals and their environment, they could still do fine (there are many such examples).

Hybrids from different species or genera, however, have almost zero conservation value. This is one reason I am opposed to allowing more distant crosses in captivity ... the other being that interspecific hybrids also tend to have reduced health and/or fertility.



Madkins007 said:


> Look at ball pythons. I do not like the vast majority of the color morphs, but all of that focus has really brought out a lot of good info on cares for the species, as well as driving the prices of 'plain' animals down. (I know color morphs are not the same thing as interspecies hybrids, but the overall lesson, I believe, is about the same.)



Right, morphs are not hybrids, so it's not the same thing. However, I don't think I could ever get one, because they are so different from their wild-type ancestors.

As a general rule, I don't see the point of altering animals to a great extent from the wild-type. Some change is inevitable, of course, so that they can live with people, adapt to captivity, do certain jobs, etc. But it seems like most large changes are to the detriment of the animal. Highly derived dog breeds become inbred, have trouble breathing or moving, are too small to defend themselves, etc. Racing horses may have brittle bones. And many captive strains of fish and reptiles would not survive without human aid.

I see your point about drumming up interest, but why can't we just leave well enough alone? Is it worth it to create a stir at the expense of the animals doing the stirring? I don't think so. I think people should appreciate animals for what they are, and not what we can make of them.


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## Hyazintharar (Jul 11, 2012)

GeoTerraTestudo said:


> StudentoftheReptile said:
> 
> 
> > On a slightly different note, I want to preface my following statements with something my late grandfather said: "In a 100 years from now, no one will know the difference." Now, some may take a little offense to that in matters like this, but let's look at the big picture here. The planet as a whole is spiraling downward in an irreversible path all across the board: economically, politically, and environmentally. We're so worried about this Noah's Ark scenario, but seriously, at the rate we're decimating entire ecosystems, flattening forests, bull-dozing grasslands, polluting waterways, etc....how imperative is it that we have every single subspecies of say, leopard tortoise? Heck, 50 yrs from now, I'd be happy just to still be able to get a leopard tortoise period if I wanted one! I know a lot of this could be doomsday speculation, but there could honestly come the day where there will be more of a said species in captivity, then there is in the wild. Heck, with some species, this is already the case.
> ...





I appreciate very much your knowlege and the way you are thinking. But mankind is curious . Myself I am breeding G. Platynota and I hope that I can help with successfull breeding avoiding the exstinction of this most friendnly, beautifull tortoise.
I have traveled Mynmar to better understand the natural habitat of the Platynota and visited two Platynota wildlife sanctuaries there (who are not very successfull in mating young G. platynotas). That means to bring back Platynotas to Myanmar will not help to survive the species - they will become captured and eated or their habitat will be destroid. The survival at the moment for G. Platynota can only be guaranteed by successfull breeding in captivity followed by a diaspora through tortoise freaks and rebreeding by pet holders. But why I say that in this tread? I also have 12 subadult A.radiata who will become fertil in the comming years. Could interbreeding G..Platynota with A.Radiata be possible ? How could this look like ? I have to confess I am very curious about this question. For shure, if interbreeding would happen I would not stop it if the two kind of tortoises would choose the other species as partner.
( But to be honest, I do not believe that interbreeding between this two gorgious species would work. But If it will work, you will see pictures!)


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## CactusVinnie (Jul 12, 2012)

Very fine thread... as usual.

Hyazintharar,

It is to appreciate your interest in visiting originar habitat of your chelonians, but, sorry to put it this way, the idea of:



Hyazintharar said:


> ... if interbreeding would happen I would not stop it if the two kind of tortoises would choose the other species as partner [...] ... If it will work, you will see pictures!



... pretty anulate you strong interest on them... especially when it's about endangered species... and *chelonians*, more than anything!!
Be sure that tortoises and turtles don't give a dime if you will be intolerant to their zoophilic (if they choose a partner from another species) or homosexual tendencies... they will not sue you for that and calling you a bigot. Only humans do that. 
Well, some French/Macedonian/Serbian smart(+//) biologists _(I don't know who had the first this spark of genius... I'll bet rather the French, since Macedonians and Serbs are quite... "primitive", and such profound understanding of life is not quite their cup of tea, LUCKILY)_ took very wrong the domination ritual between some wild Boettgeri males, calling them "straight" and "homosexual group"... My God!!!!

As we Romanians say... "So large is the God's Garden... but many manage to skip the fence..."

Please, try to reject that idea from the start... it gave me creeps. It is a shame to even think about, and better use your knowledge for tortoises interest, not for fun or curiosity- these superficial and futile things will fade away someday, but the poor live creatures remain (if hybridisation succeeds)... first day jawdroppers, next day forgotten... and they have no fault for that. Those wonders are not our ridiculous toys. You cannot mock Creation and evolution this way. It is "haram"  (no, I'm not Muslim).


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## GeoTerraTestudo (Jul 12, 2012)

Hyazintharar said:


> I appreciate very much your knowlege and the way you are thinking. But mankind is curious . Myself I am breeding G. Platynota and I hope that I can help with successfull breeding avoiding the exstinction of this most friendnly, beautifull tortoise.
> I have traveled Mynmar to better understand the natural habitat of the Platynota and visited two Platynota wildlife sanctuaries there (who are not very successfull in mating young G. platynotas). That means to bring back Platynotas to Myanmar will not help to survive the species - they will become captured and eated or their habitat will be destroid. The survival at the moment for G. Platynota can only be guaranteed by successfull breeding in captivity followed by a diaspora through tortoise freaks and rebreeding by pet holders. But why I say that in this tread? I also have 12 subadult A.radiata who will become fertil in the comming years. Could interbreeding G..Platynota with A.Radiata be possible ? How could this look like ? I have to confess I am very curious about this question. For shure, if interbreeding would happen I would not stop it if the two kind of tortoises would choose the other species as partner.
> ( But to be honest, I do not believe that interbreeding between this two gorgious species would work. But If it will work, you will see pictures!)



It is so sad how endangered tortoises have become. If you are legally keeping Burmese stars (_Geochelone platynota_), then I hope they will breed for you. Likewise, if you are legally keeping radiated tortoises (_Astrochelys radiata_), I hope they breed, too. However, you should keep these two species separate for two reasons. One is preventing the spread of diseases, and the other is the possibility of hybridization. Although Burmese stars and radiated tortoises are distantly related (they are in different genera), they still might mate under captive conditions. In that case, they could produce hybrid offspring. I suspect such hybrids would have reduced viability and/or fertility, but they might not. In that case, distant hybrids might be introduced into the trade. Such animals would probably have traits intermediate between their parent species, but would probably not be as well-adapted to Burma or Madagascar as either parent species. Best to avoid this and not risk it.

I don't know if Burmese stars have ever hybridized with their sister species, the Indian star (_G. elegans_), or if radiated tortoises have ever hybridized with their sister species, the ploughshare tortoise (_A. yniphora_). Because each of these pairs is closely related, the hybrid offspring would probably be viable, and might even be fertile. I think these crosses are to be avoided, too, but given how endangered these animals are, it might be necessary to resort to such crossings in the not-so-distant future to keep these lineages alive.


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## Hyazintharar (Jul 13, 2012)

Maybe im have not clearly enough expressed my goals as breeder.

My goal is helping to avoid the exstinction of G. Platynota and not producing hybrids. I made e lot of effort to breed successfully G. Platynota and I am very happy to found out many secrets of successfully mating Platynota . I do the breeding of G. Platynota as passion, and not with commercial ideas ( I have more money I need for life, I am not interesteted to let grow my money and my values.
Therfore I sell platynata hachlings only as exeption and only to people with enough background and further breeding intentions. My Platynota survival foundation organise discrete connections between Platynota breeders worldwide, to interfer breeding knowlege, without publicity. 
By thevway - My Platynota survival foundation do not accept donations! . (By the way- people who know german are invited to read my article about G. platynota in the online-magazine: www.testudina.de [click on the .pdf file]).

But however, it is my experiance, that A. radiata and G. Platynota (also together with G. elegans) can be very well held in same big outdoor enclosures. They more or less eat the same diet (and all my tortoises have the same intestinal flora), are never agressiv again each other or between males and females . (As M.D. I supervise and treat my animals myself). However the Indoor encloseres are never together and I try to avoid hybridisation. So I have no hybrids till today nor have I actvely tried to produce.

But, if a hybridisation would once occour between a Platynota and a Radiata (it is not even shure it could - not only the genetics are quite far from each other, but alson mating rituals are different. Till now I had never the impression, that Radiata and Platynota attract each other by their smell), my opinion still remains the same as I write before: I would be curious how such a hybrid looks like . In my opinion a hybrid tortoise would be still better than no tortoise. 
Fortunately we all , the people in Switzerland and the people in the US have the right of their own different opinions - so I think we have not to end on a single same opinion.


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