Posted on 09/08/2016 11:16:42 AM PDT by JimSEA
Horses and donkeys are seperate species, the existance of mules notwithstanding. The key being that mules (like the “ligers” you referred to) are sterile. Since they cannot reproduce, mules are not even a species biologically speaking. To be considered a single species, the offspring must be capable of reproduction.
Never. All sexually mature humans are quite capable of producing children with any human of the opposite sex, regardless of race. We are a single species.
Well, camels and giraffes are both “even-toed ungulates”, so they are generally similar, but even whales are placed in that same grouping so it’s a pretty broad classification.
Yes, sorry if I was unclear. You also assume significant difference in habitat, etc.
“All sexually mature humans are quite capable of producing children with any human of the opposite sex, regardless of race.”
That’s not a valid test anymore though, in terms of modern taxonomy. It doesn’t matter if they are capable of producing offspring, if circumstances in nature prevent them from actually ever producing offspring, then scientists classify them as different species. So, for example, if there are 2 groups of chimps who live on opposite sides of a river, and they cannot cross the river, it doesn’t matter if they could produce offspring, they would still be considered separate species.
Humans obviously can traverse any of those kinds of obstacles, so I don’t think scientists would consider us separate species. However, 600 years ago, if they were using the current standards, humans in the Western hemisphere would have had to be considered a separate species from humans in the Eastern hemisphere.
Actually, the key words are “and for greater conservation efforts”.
Eco-nazis use genetics to declares species “unique” and thereby fend off development.
I figure it’s only a matter of time before they don’t even bother with that and just based it on location as in,
“There’s only one frog on your property, well then, the ‘123-Main-St bullfrog’ you have there needs to be protected so stop going in your yard and doing things like mow the lawn.”
So what are they implying, that instead of one prevalent species we now have four endangered species?
-PJ
“Lions and tigers are separate species but on rare occasions mate and produce offspring.”
Really, any kind of feline can breed with any other kind of feline, barring some physiological impediments like great size differences. There is so little genetic diversity in the felines that, even though we consider them separate species, it is obvious that they are all very closely related.
I don’t know their criteria but a reduction in composite numbers of the four species from 150,000 to 100,000 individuals is pretty significant regardless of how you group them. Add to that the facts that reproduction rates are relatively slow - low numbers, long childhood, long life span, etc. and I can understand concern but not draconian limitations on predators.
Yes, literally by definition - "significant" being determined by the fact of creating enough competitive stress to compel genetic differentiation.
Whales? But, but (I’m going to have to expose more of my ignorance here) but last time I looked, Whales don’t have any toes at all! I DO see Whales under the category of CETACEANS; which are placental marine mammals.
There is probably a linkage that I overlooked. Interesting to study either way. I miss watching the Nature Channel. No TV now.
Interesting point. And logical, if the formerly one prevalent species was endangered.
Well, they believe cetaceans evolved from even-toed ungulates, so technically whales are a branch of the family. I guess it doesn’t matter if the toes are now just bones embedded in a fin.
Not all big cat can interbreed and those who can must be raised together. Cheetahs are for cheetahs alone. Had to look that up because of the fairly frequent news about ligers.
I was on an interview and part of the company’s interviewing process was to ask off the wall questions to see how one responds. I was asked to tell a clean joke and then someone on the panel asked me the following question.
There is a giraffe in your backyard. What would you do to remove him? It was apparent they were expecting a logical response as to the process I would use to remove the unwanted visitor. But I couldn’t help myself, “Is the giraffe alive or dead?”
Interview over.
I hope you got the job. That’s an executive level answer. I’d have put you in charge of Meetings Efficiency.
If the many secret societies of the world have any say - never. They'd all be out of business.
Deb: What's a liger?
Napoleon Dynamite: It's pretty much my favorite animal. It's like a lion and a tiger mixed... bred for its skills in magic.
Yes, that’s right, I forgot about Cheetahs, but in their case, it seems to be because they are a very isolated group that has lost even more diversity than the rest of the felines, not because they are any more distantly related. They just bred among themselves for a very long time apparently.
Had to look it up -
While it's true that mules are sterile, "ligers" and "tigons" are NOT. Wiki sez that male hybrids are sterile, but females have successfully bred (with tigers or lions).
So now we got three situations: Mules - all sterile
Male ligers and tigons - sterile
Female ligers and tigons - viable
Which are true separate species, and which are not?
To be considered a single species, the offspring must be capable of reproduction.
Guess that answers my question. While female ligers and tigons can mate, there are no viable male tigons or ligers to mate with. The next generation would be only 1/4 tiger or 1/4 lion, then 1/8 in the next iteration, etc. Wonder how many generations until a male is no longer sterile?
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