Interspecies Reproduction

[ICantSpellDawg]

Can someone explain to me interspecies reproduction. I have read about Coyotes and Wolves/Dogs interbreeding and they are two distinct species under the same Genus. Their offspring are even able to reproduce!

What is the real qualification of whether something is a different species?

Why couldn't a male from one species in the Genus Homo interbreed with a female from another? Why are different ethnicities so different, yet called part of the same species? Why is it impossible that early offshoots in the Genus Homo had interspecies relationships?

Is the term ethnicity just a politically correct term for sub-species? or even species?

(I understand the concept of Clinal and polytypic species, but at what point do you draw the line between the crests and troughs of a cline and a different species entirely? Interbreeding can't be that point)

Please talk about this in depth.

[Philippus Flavius Homovallumus]

IRRC the line of demarcation is the ability to breed fertile offspring, so wolves and at least some dogs are the same species.

[ICantSpellDawg]

IRRC the line of demarcation is the ability to breed fertile offspring, so wolves and at least some dogs are the same species.

but what I wrote is that Coyotes are technically another species than dogs/wolves under the same genus, but they produce fertile offspring.

Horses and donkeys produce fertile offspring 2% of the time.

"According to Wild Cats of the World (1975) by C. A. W. 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, although of delicate health, was raised to adulthood"

[FactionHeir]

Backcrossing usually is possible with a female hybrid, as males tend to be sterile in general. Also, hybrids in most cases cannot reproduce further "hybrids" with each other, and if they can, those tend to be less fit.

As for different species happily interbreeding, its likely that they simply have not diverged (speciated) to a great enough extent to lead to reproductive isolation, which can be due to separation happening not too long ago (in evolutionary terms) or cases where one group member was able to breed with a member of another group, hence setting the speciation event back quite a bit.

Most speciation tends to occur as a result of geographical barriers, although there are certainly exceptions.

[drone]

Can someone explain to me interspecies reproduction. I have read about Coyotes and Wolves/Dogs interbreeding and they are two distinct species under the same Genus. Their offspring are even able to reproduce!

What is the real qualification of whether something is a different species?

Why couldn't a male from one species in the Genus Homo interbreed with a female from another? Why are different ethnicities so different, yet called part of the same species? Why is it impossible that early offshoots in the Genus Homo had interspecies relationships?

For Canis, there are no real genetic differences from wolf to Great Dane to poodle. Most domesticated dog breeds are just tamed wolves bred for certain characteristics over centuries. Aside from possible problems with the birth canal, coyotes, dingos, and wolves (and maybe some jackals) can breed fertile offspring with domestic dogs. In my mind, they are really just different breeds, not different species, but I don't make the rules.

I also tend to think of ethnicity the same way, I would be the same species as an Asian or African, just different characteristics bred in to survive in the environments of our ancestors.

Mules might be a better example here. Horses and donkeys are classed as different species of the same Genus (Equus), but have different numbers of chromosomes, which causes the offspring to be infertile. Other problems may arise from specialized fertility cycles, incompatible sex organs, optimal fertilization temperature, and a whole slew of slight chemical and biological issues.

I don't think the official species classifications takes interbreeding possibilities into account, they mainly deal with physical, behavioral, and environmental differences.

[ICantSpellDawg]

For Canis, there are no real genetic differences from wolf to Great Dane to poodle. Most domesticated dog breeds are just tamed wolves bred for certain characteristics over centuries. Aside from possible problems with the birth canal, coyotes, dingos, and wolves (and maybe some jackals) can breed fertile offspring with domestic dogs. In my mind, they are really just different breeds, not different species, but I don't make the rules.

I also tend to think of ethnicity the same way, I would be the same species as an Asian or African, just different characteristics bred in to survive in the environments of our ancestors.

Mules might be a better example here. Horses and donkeys are classed as different species of the same Genus (Equus), but have different numbers of chromosomes, which causes the offspring to be infertile. Other problems may arise from specialized fertility cycles, incompatible sex organs, optimal fertilization temperature, and a whole slew of slight chemical and biological issues.

I don't think the official species classifications takes interbreeding possibilities into account, they mainly deal with physical, behavioral, and environmental differences.

http://en.wikipedia.org/wiki/Coyote
http://en.wikipedia.org/wiki/Wolf

Clearly two distinct species under the same genus who actually mate in the wild. Not a subspecies.

http://en.wikipedia.org/wiki/Red_wolf

The Red wolf seems to be fertile hybrid of both a coyote and a wolf

[Papewaio]

Just remember that most of the rules of naming conventions predate DNA analysis.

So the taxonomy of naming and dividing is based on phenotypes and not on its entire DNA.

[drone]

http://en.wikipedia.org/wiki/Coyote
http://en.wikipedia.org/wiki/Wolf

Clearly two distinct species under the same genus who actually mate in the wild. Not a subspecies.

http://en.wikipedia.org/wiki/Red_wolf

The Red wolf seems to be fertile hybrid of both a coyote and a wolf

I understand that they are classed as different species, but I also don't agree with the official species classifications (for Canis, anyway). My dogs' breed (Siberian Huskies) dates back thousands of years, and supposedly had wolves bred back in occasionally to maintain endurance. Coyotes are currently jumping fences and impregnating female dogs in the DC suburbs on a regular basis. Canis is just a bad example, since "dogs" are pretty much all the same genes.

What Pape said ^^^^^

[ICantSpellDawg]

I understand that they are classed as different species, but I also don't agree with the official species classifications (for Canis, anyway). My dogs' breed (Siberian Huskies) dates back thousands of years, and supposedly had wolves bred back in occasionally to maintain endurance. Coyotes are currently jumping fences and impregnating female dogs in the DC suburbs on a regular basis. Canis is just a bad example, since "dogs" are pretty much all the same genes.

What Pape said ^^^^^

But domesticated dogs and wolves are canis lupis; part of the same species, so it follows that they can breed. Coyotes are not, yet they can still breed with dogs. I think it is odd and interesting. There must be a strong enough reason to seperate coyotes from dogs/wolves. Can someone explain it to me?

[drone]

I'm not sure who was responsible for making the classifications for Canis (or the Canidae family in general), but they probably decided that the behavioral and physical differences were great enough to qualify for a different species. Coyotes don't form large packs and hunt different game than wolves. If the classifications are old enough, maybe they put coyotes in a different category due to their isolation in North America.

[Papewaio]

Taxonomy is based on perceptions.

I look at the term species as one arbitrarily given for the sake of convenience to a set of individuals closely resembling each other .... it does not essentially differ from the term variety, which is given to less distinct and more fluxtuating forms. The term variety, again in comparison with mere individual difference, is also applied arbitrarily, and for mere convenience sake.

[CBR]

Wikipedia has entries on that:

http://en.wikipedia.org/wiki/Species (near the bottom " Historical development of the species concept")

http://en.wikipedia.org/wiki/Species_problem

In other words in can be rather vague and not so clear cut as it was originally thought.


CBR

[HoreTore]

I'm not sure who was responsible for making the classifications for Canis (or the Canidae family in general), but they probably decided that the behavioral and physical differences were great enough to qualify for a different species. Coyotes don't form large packs and hunt different game than wolves. If the classifications are old enough, maybe they put coyotes in a different category due to their isolation in North America.

Carolus Linnea in his work Systema Naturae was the maker of the classifications we use today. The first edition came out in 1735, so even pre-darwin(1859).

Oh, and the classification stops at "specie", it doesn't include "sub-specie".

[Fragony]

wasn't me

[macsen rufus]

"Species" is a linguistic concept devised and used by humans.

Organisms are a genetically diverse range of products of DNA recombination, the full degree of variability of which we do not yet fully comprehend.

As our knowledge progresses, I'm sure we'll use the concept of species less and less and develop terminology more suited to the realities of DNA. I personally don't believe that the idea of "species" as used by humans has any real grounding in an objectiively identifiable reality, it is at best an approximation that allows us to group vaguely similar things together so we can make some sense of the bewildering variety of life.

And Fragony....

Spoiler Alert, click show to read: 

[Viking]

"According to Wild Cats of the World (1975) by C. A. W. 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, although of delicate health, was raised to adulthood"

It mated with a lion, and not another hybrid.

[Cheetah]

Can someone explain to me interspecies reproduction. I have read about Coyotes and Wolves/Dogs interbreeding and they are two distinct species under the same Genus. Their offspring are even able to reproduce!

Coyotes and Wolves are recognized as a different species because of their morphological differences and because in the wild they rarely (if ever) crossbreed.

What is the real qualification of whether something is a different species?

From wiki:
Biological Species Concept (BSC), which is that a species consists of populations of organisms that can reproduce with one another and that are reproductively isolated from other such populations.
(after Earnst Mayr)

That is the most accepted species concept for sexually reproducing species. It may or may not apply for asexual species. The situation is lot more complicated though. For historical reasons almost each scientific subfield has its own (or several of its own) species definitions. Definitions that work for a zoologist might not work someone working with fossils. for example the above BSC cannot be used to classify fossils as you cannot tell anything about populations reproductive isolation.
Traditionally species concept were mostly based on morphology (for obvious) reasons. Thus it happened that the different sex or even the young of a given species were classified as an independent species because of the profound morphological differences. It took a while, and of course required the detailed knowledge of the life-cycle of these species to discover that these forms belong to one species.
Eventually it was Darwin's theory of common descent that changed the picture. According to it species originate by splitting from an ancient form, thus in evolutionarily terms a species is an idenpendent evolutionarily lineage. This recognition was the stepping stone for Mayr's species definition, as quoted above.
So in theory there are two ways to identify species. First one the BSC is to look for reproductive isolation in nature. The second one, looking from an evolutionarily perspective is to search for independent evolutionary lineages. Of course, the first (i.e. reprodcutive isolation) is a requirement for the second. Alas, as said, these approaches cannot be always used in practice and might not be useful for such asexually reproducing "species" like bacteria, where horizontal gene transfer is quite common between different lineages.
So, for practical and historical reasons the role of visible morhpological features in classification is still important and in many cases it is a matter historical consensus whether we call a given population a sub-species or species.

Why couldn't a male from one species in the Genus Homo interbreed with a female from another?

Probably because the differences in the organization of the genom is large enough to case malefunctions during develompent. TBH I do not know about cross-breeding experiments.

Why are different ethnicities so different, yet called part of the same species?

Because we are using BSC, and members of different ethnicities can and do breed together, i.e. there is no reproductive isolation in nature (despite the morhological differences).

Why is it impossible that early offshoots in the Genus Homo had interspecies relationships?

It is not impossible, actually it is quite debated. For example some suggests that neanderthals could have crossbreeded with H.sapiens (though most would disagree).

Is the term ethnicity just a politically correct term for sub-species? or even species?

No. It is a culturaly loaded term for race.
see wiki for race:http://en.wikipedia.org/wiki/Race_and_genetics

[Cheetah]

Carolus Linnea in his work Systema Naturae was the maker of the classifications we use today. The first edition came out in 1735, so even pre-darwin(1859).

Oh, and the classification stops at "specie", it doesn't include "sub-specie".

Linneaus introduced a new methodology of classification, both in terms of hierarchy (species-genus-order-class system) and the binominal nomenclature. Needles to say both were immensly useful, hence we are still using these uptoday.
However, the actual classifications he proposed were quite simple and eventually turned oboslete. For animals he proposed only six group, and he classified plants based only on sexual caracters (which gave a highly artifical classification- in terms of common descent).
So while his methodology is still being used his actual classifications were long forgotten.
Yet, exactly because he introduced these systems many scientific names date back to him. He named mammalia as well as Homo sapiens.

[Cheetah]

"Species" is a linguistic concept devised and used by humans.

That is the so called "nominalistic" position, but most biologist would disagree. In one sense of course, it is a linguistic concept, but different evolutionarly lineages do exist in nature.

Organisms are a genetically diverse range of products of DNA recombination, the full degree of variability of which we do not yet fully comprehend.

The very problem is that one cannot observe a "full degree of variability" in nature. Neither in terms of morhology nor in terms of DNA. There is discontinuity, and the origin and maintenance of this discontinuity is one of the major problems in biology.
Actually, Dobzhansky (one of the fathers of the "new synthesis") was the first to recognize this problem, and wrote a book about this quite long ago (in 1937). http://en.wikipedia.org/wiki/Dobzhansky

As our knowledge progresses, I'm sure we'll use the concept of species less and less and develop terminology more suited to the realities of DNA. I personally don't believe that the idea of "species" as used by humans has any real grounding in an objectiively identifiable reality, it is at best an approximation that allows us to group vaguely similar things together so we can make some sense of the bewildering variety of life.

It has a real ground for sexually reproducing species, though it may or may not have a real ground for asexual "species". Also, DNA can help you to build an evolutionary tree (i.e. a representation of descent) but you still need certain rules to make a system of classification out of that tree.

[ICantSpellDawg]

- The problem with Dual Homo Sapien Migration Routes.

- DNA tests misleading people

- *****Possible Neandertal-Sapien Hybrids

With the last one, I know that DNA doesn't suggest the possibility, but with his previous post about how DNA tests mislead people about ancient realities...


Also, Coyotes and Dogs/Wolves occupy overlapping geographic areas and "rarely" reproduce and create fertile offspring. However, this mating is without human instigation AND can add up to quite a bit over time. This, along with other exceptions, just confuses the definition of species.

[HoreTore]

Linneaus introduced a new methodology of classification, both in terms of hierarchy (species-genus-order-class system) and the binominal nomenclature. Needles to say both were immensly useful, hence we are still using these uptoday.
However, the actual classifications he proposed were quite simple and eventually turned oboslete. For animals he proposed only six group, and he classified plants based only on sexual caracters (which gave a highly artifical classification- in terms of common descent).
So while his methodology is still being used his actual classifications were long forgotten.
Yet, exactly because he introduced these systems many scientific names date back to him. He named mammalia as well as Homo sapiens.

It has flaws? It was made by a Swede. Go figure.

[Big_John]

Also, Coyotes and Dogs/Wolves occupy overlapping geographic areas and "rarely" reproduce and create fertile offspring. However, this mating is without human instigation AND can add up to quite a bit over time. This, along with other exceptions, just confuses the definition of species.

as has been pointed out, you're dealing with a couple of anachronistic definitions of species. the idea that no member of a 'species' should ever be able to produce non-sterile hybrids with members of another 'species', no matter how closely related, is 19th century thinking. even basic darwinism can account for that phenomenon.

scientific nomenclature of species, as has been said, relied predominantly on distinction of phenotypes. obviously, the system has it's flaws. the coyote example indicates that evolution is certainly a gradual process, at least on some baseline. paleontology indicates that they diverged from a common ancestor with gray wolves ~ 2-2.5 millions years ago. depending on the life span, reproductive frequency, selective pressures, and biological isolation, this can be more than enough time for speciation (following the old rule of validity of offspring, for the moment), or way too little time. in the case of coyotes, we seem to be catching them in the early stages of old-style speciation. coyotes were described as a distinct species in 1832, after all. but there is a systematic, significant difference in the phenotypes (and probably genotypes, by extension) between coyotes and wolves. give evolution more time, and we'll probably see inviability rear it's ugly head.

applying that idea of mine (and it is just arm waving), horses and donkeys would appear to be in the last stages of old-style speciation, with occasional hold-outs appearing 2% of the time. lions and tigers, more so.

humans wouldn't even be in the first stages of this definition of speciation. the genetic homogeneity is too substantial. we'd probably need several millions of years of isolated evolution for races to diverge into the first stages of separate species. and that'd still only happen if the selective pressures were adequately different in the areas occupied by the different phenotypes. the difference in phenotype between human races isn't nearly as systematic or substantial as between wolves and coyotes, btw. i don't know anything about the genetic distance between wolves and coyotes, but i'd guess the same applies there.

[Vladimir]

He *is* among us!

And along the lines of human genetics: It's amazing how genetically similar we are. There was a period not too long ago where we were reduced to maybe several thousand worldwide. It's hard to be a racist once you know the truth of our genes.

[ICantSpellDawg]

as has been pointed out, you're dealing with a couple of anachronistic definitions of species. the idea that no member of a 'species' should ever be able to produce non-sterile hybrids with members of another 'species', no matter how closely related, is 19th century thinking. even basic darwinism can account for that phenomenon.

scientific nomenclature of species, as has been said, relied predominantly on distinction of phenotypes. obviously, the system has it's flaws. the coyote example indicates that evolution is certainly a gradual process, at least on some baseline. paleontology indicates that they diverged from a common ancestor with gray wolves ~ 2-2.5 millions years ago. depending on the life span, reproductive frequency, selective pressures, and biological isolation, this can be more than enough time for speciation (following the old rule of validity of offspring, for the moment), or way too little time. in the case of coyotes, we seem to be catching them in the early stages of old-style speciation. coyotes were described as a distinct species in 1832, after all. but there is a systematic, significant difference in the phenotypes (and probably genotypes, by extension) between coyotes and wolves. give evolution more time, and we'll probably see inviability rear it's ugly head.

applying that idea of mine (and it is just arm waving), horses and donkeys would appear to be in the last stages of old-style speciation, with occasional hold-outs appearing 2% of the time. lions and tigers, more so.

humans wouldn't even be in the first stages of this definition of speciation. the genetic homogeneity is too substantial. we'd probably need several millions of years of isolated evolution for races to diverge into the first stages of separate species. and that'd still only happen if the selective pressures were adequately different in the areas occupied by the different phenotypes. the difference in phenotype between human races isn't nearly as systematic or substantial as between wolves and coyotes, btw. i don't know anything about the genetic distance between wolves and coyotes, but i'd guess the same applies there.

Yes okay. That is an answer that I understand and guessed. http://en.wikipedia.org/wiki/Red_Wolf - the red wolf is so interesting. It FREQUENTLY mates with both coyote and grey wolf and is indistinguishable genetically from both. This animal is a missing link.

I think that until the introduction of the camel to north africa, humans were on a divergent evolutionary path, seperating sub-saharan africa from the rest of the world.

I also think that homo sapiens mated and reproduced fertile offspring with cousin branches of the genus homo. The genes could have died out already (as implied by DNA testing) OR they could just be hard to recognize. People have said that Celtic genes have become extinct in the short time since their integration with other peoples, why not Neanderthal contributing Y chromosomes 30,000 years ago? It would help explain the hair and eye color difference and how it could have appeared so (relatively) quickly after our recent arrival into Europe. I realize that there are other explanations as to how this could occur.

[Vladimir]

I also think that homo sapiens mated and reproduced fertile offspring with cousin branches of the genus homo.

Do I have to say it?


Anyway

As far as your point about European evolution: Don't underestimate the importance of Vitamin D in maintaining your health. New studies suggest that it has a powerful affect on longevity and general health.

[ICantSpellDawg]

Do I have to say it?

say what?
I wouldn't put money on it, but a number of people who actually know what they are talking about say that it is a possibility. (the neandertal thing)

[Big_John]

the evidence for neanderthal contribution to the modern human genepool is tentative, at best. also, there appears to be almost no cultural contribution from neanderthals to humans, which is something of an argument against interbreeding, but certainly not a conclusive one.

do remember that the genetic sequencing of neaderthals is a tricky proposition, obviously.

[Vladimir]

say what?
I wouldn't put money on it, but a number of people who actually know what they are talking about say that it is a possibility. (the neandertal thing)

My fellow American, homos can't reproduce.

[Papewaio]

We are all homo's.

[Quietus]

Can someone explain to me interspecies reproduction. I have read about Coyotes and Wolves/Dogs interbreeding and they are two distinct species under the same Genus. Their offspring are even able to reproduce!

What is the real qualification of whether something is a different species?

Why couldn't a male from one species in the Genus Homo interbreed with a female from another? Why are different ethnicities so different, yet called part of the same species? Why is it impossible that early offshoots in the Genus Homo had interspecies relationships?

Is the term ethnicity just a politically correct term for sub-species? or even species?

(I understand the concept of Clinal and polytypic species, but at what point do you draw the line between the crests and troughs of a cline and a different species entirely? Interbreeding can't be that point)

Please talk about this in depth.

The DNA must must be compatible enough. It's the dna from the gametes that are essentially interacting you see (since they code for the proteins). The sperm won't even bind/penetrate the egg if they are completely different. Think of it as a series of doors. Each stage lead to another door. You must have the correct keys all the time. And the keys are dependent on the DNA. All the doors are depenent on the dna too. That's a simple way of putting it.

It's highly ordered reaction one after the other until one is born up to one's death. hence one can really argue that life starts when the sperm hits the egg.