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So here is something I may need to write into an article here at some point. Most pet keepers are used to "breeds". But, most reptiles are actually grouped into species.

The definition of breed [noun]:
A group of usually domesticated animals or plants presumably related by descent from common ancestors and visibly similar in most characters

The term species can be defined in a few different ways, but here we are going with the basic biological definition:
A fundamental category of taxonomic classification, ranking below a genus or subgenus and consisting of related organisms capable of interbreeding.

Now, you could say that a "breed" of dog could fit that definition, and that is true. But, EVERY breed of dog could together fit that definition, because, they are all the same species.

Let's think back to taxonomy taught in basic biology, the ranks of biological classification:

Kingdom
Phylum
Class
Order
Family
Genus
Species

All breeds of domestic dogs, pit bulls, jack russels, cocker spaniels, are the same subspecies, Canis lupus familiaris, so even a level below species. All domestic cats are the same species, Felis catus.

There are obviously things that don't fit, Savannah cats for example, are crossed with wild Servals. But a siamese, a maine coon, a persian, are all the same family, genus, and species.

Now, with snakes, people here the word "python", and think they are all the same, and "boa", and they are all the same. This is not correct. Pythons refer to the taxonomic family Pythonidae, and boas to the taxonomic family Boidae. They are both in the order Squamata.

For reference, "cats" (all cats big and small) are in the family Felidae and all "dogs" (including wolves) are in the family Canidae. They are both in the Order Carnivora.

So what does this realistically mean? It means that comparing a ball python (Family: Pythonidae, Python regius) to a common boa (Family Boidae, Boa constrictor imperator), is the equivalent to comparing how to keep a pekingese to how to keep a Bengal tiger. They are as genetically dissimilar. In fact, human beings are more closely related to chimpanzees, on a genetic level, than any boa is to any python that has been tested.

This could go on to a lengthy debate, and I am not a qualified biologist, but hopefully this explains to an extent why there aren't simple answers to how to keep a "snake". Just because it doesn't have legs and is a reptile doesn't mean they are as similar as one may think. Cats, bats, wolverines and polar bears all have legs, and are mammals but are very different.
Make sense. Thanks for clarify.

Please correct me if I am wrong. Smile
Same species can have different breeds. Obviously these different breeds of the same species can "cross-breed" together, and their offspring can still reproduce without a problem.

It is not the same case when the "cross" is between different species. Think about liger (cross between tiger and lion), or mule (cross between donkey and horse). These cross-species breeding usually result in offsprings without the ability to reproduce again.
(10-07-2013, 10:20 PM)Thor Wrote: [ -> ]Make sense. Thanks for clarify.

Please correct me if I am wrong. Smile
Same species can have different breeds. Obviously these different breeds of the same species can "cross-breed" together, and their offspring can still reproduce without a problem.

Absolutely. That is why when you have different "breeds" of dogs or cats they can breed quite successfully and the offspring is fertile. I really hate to use this analogy, but you could use the analogy of different "races" of people. A "black" person can have children with a "white" person, that are as healthy as if they weren't "crossed". Because we are all the same species, even the same subspecies. No matter the outward differences.

The concept of breeds is slightly crossing into reptiles. Green tree pythons are a god example, having many different phenotypes that can be crossed and bred into specifically desired appearances, with all of the offspring being completely viable. Though few of the breeders like that comparison.

(10-07-2013, 10:20 PM)Thor Wrote: [ -> ]It is not the same case when the "cross" is between different species. Think about liger (cross between tiger and lion), or mule (cross between donkey and horse). These cross-species breeding usually result in offsprings without the ability to reproduce again.

Now, in true hybrids, it is far from simple. Reptiles seem to hybridize much easier than mammals. And the results can be anywhere from seemingly infertile, to fertile, to in-between. Though, in most cases, reduced fertility seems to be the case. Especially with males. For example, there is a hybrid reptile, commonly called a "carpondro", which is a cross of a carpet python bred to a green tree python. In most cases, the female carpondros can be bred to either a male green tree python or carpet python. But male carpondros have had very few successful breeding attempts with any other animals.

Which leads one to wonder whether or not it is just the "odds" that are against the hybrids you mentioned. If a snake can only hatch out of 2-5 of 10-20 eggs, that is roughly a 25% successful hatch rate. In mammals with small numbers of babies (mules for example), that would mean that each single baby only has a 25% chance of developing full term. Obviously there are other mitigating factors, and this over simplifies things, but you get the idea. Hybrids have extremely reduced fertility as far as the evidence shows, and the actual fertility is is variable in each hybrid combination.