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View Full Version : Wolphins? They're fertile???



dgruss23
2005-Apr-20, 02:52 PM
My wife told me about this today. Apparently a dolphin crossed with a whale - hence a wolphin. That in itself was surprising, but now then the wolphin crossed with a pure dolphin and actually produced an offspring.

Here (http://hotspotshawaii.com/Wolphin.html) is an article. And here (http://seattlepi.nwsource.com/national/apscience_story.asp?category=1501&slug=Wholphin%20 Birth) is a more recent one.

What implications does this have for genetics, our definition of "species", and evolutionary theory (re: modes of evolutionary change)? Any thoughts?

George
2005-Apr-20, 02:59 PM
Quite interesting. I don't recall seeing aquatic crosses (I'd be one the last to know though).

Why would the genetics issue be any different than crossing other animals such as pigeons or cattle?

The Supreme Canuck
2005-Apr-20, 02:59 PM
Actually, wolphins are a cross between a dolphin and another kind of dolphin frequently confused with a whale (called False Killer Whales). Sometimes the offspring is fertile, sometimes not. The big debate is whether the offspring of the offspring is fertile.

BTW, ToSeeked: http://www.badastronomy.com/phpBB/viewtopic.php?t=21043&

dgruss23
2005-Apr-20, 03:25 PM
Quite interesting. I don't recall seeing aquatic crosses (I'd be one the last to know though).

Why would the genetics issue be any different than crossing other animals such as pigeons or cattle?

Domesticated pigeons are all the same species so they're genetically compatible. I'm not sure about cattle - do all breeds originate from the same ancestral stock?

My question is what - if any - implications this has for our definitions of species. Generally it is understood that individuals of different species cannot produce fertile offspring (Mules are not fertile). But in this case it happened. Does that mean the two species have only recently diverged? Are they an example of an evolutionary intermediate between two populations that are now almost completely distinct species? Has there been any research into the genetic comparison of these two species and the time since they might have been the same?

George
2005-Apr-20, 03:46 PM
.. do all breeds originate from the same ancestral stock?
Cattle are crossed with other species..... cattle (http://cattle-today.com/)

Both dolphin species were crossed, so it seems it may be similar to cattle crossing. However, I really only know about the cattle crossings you drive over. :wink:

the_shaggy_one
2005-Apr-20, 03:54 PM
If I remember, Lions and Tigers can also procreate, with most being infertile. Female Ligers (offspring of a male lion and a female tiger) are always fertile. I can't see how this would have any new implications as far as speciation goes.

Another example of a common animal hybrid: Muskellunge and Northern Pike are crossbred to produce the Tiger Muskie, which is always sterile.

George
2005-Apr-20, 03:58 PM
Another example of a common animal hybrid: Muskellunge and Northern Pike are crossbred to produce the Tiger Muskie, which is always sterile.
I thought they were both Pike? [Caught one (34") in the lake my grandfather caught his - a 52"!. Not bad for a couple of Texans, huh? :) ]

This thread's making me wanta go fishin'. :)

Swift
2005-Apr-20, 04:01 PM
Quite interesting. I don't recall seeing aquatic crosses (I'd be one the last to know though).

Why would the genetics issue be any different than crossing other animals such as pigeons or cattle?

Domesticated pigeons are all the same species so they're genetically compatible. I'm not sure about cattle - do all breeds originate from the same ancestral stock?

My question is what - if any - implications this has for our definitions of species. Generally it is understood that individuals of different species cannot produce fertile offspring (Mules are not fertile). But in this case it happened. Does that mean the two species have only recently diverged? Are they an example of an evolutionary intermediate between two populations that are now almost completely distinct species? Has there been any research into the genetic comparison of these two species and the time since they might have been the same?
If my understanding is correct, species are not a black and white thing. There is no sharp boundary between one and other, like if more than 98% of the genes are different, its a different speices. In other words, there are degrees of separation.

the_shaggy_one
2005-Apr-20, 04:02 PM
Another example of a common animal hybrid: Muskellunge and Northern Pike are crossbred to produce the Tiger Muskie, which is always sterile.
I thought they were both Pike? [Caught one (34") in the lake my grandfather caught his - a 52"!. Not bad for a couple of Texans, huh? :-? ]

This thread's making me wanta go fishin'. :)

Nope, different species. The Northern Pike is Esox lucius, while the Muskellunge is E. masquinongy. The interesting-sounding species name is simply Ojibwa for "Ugly fish".

Can anyone guess where I'm from? :wink:

dgruss23
2005-Apr-20, 04:43 PM
It just seems that there are some profound implications from this. Tigers and lions can produce offspring -some fertile! Can't that teach us something about rates of speciation. When was the last time they could be considered the same species? How long before they are completely incompatible genetically?

Does this suggest the importance of punctuated equilibrium is less than has been thought?

Does it suggest that a key driver of speciation is not so much genetic as behavioral? (eg. species capable of interbreeding take on different "lifestyles", stop interbreeding, and thus genetically drift apart.)

Can we bring back Mastadonts by using an elephant and mastadont DNA recovered from a frozen mastadont?

Humans share 99% of the same DNA as chimps. Will a geneticist one day decide to try and fertilize chimp eggs with human sperm (or the opposite) - just to see if fertilization happens?

Disinfo Agent
2005-Apr-20, 04:52 PM
My question is what - if any - implications this has for our definitions of species. Generally it is understood that individuals of different species cannot produce fertile offspring (Mules are not fertile).
That's the general idea, but I think there are some exceptions to it (these darned inexact sciences... :P ;)).


The biological species or isolation species concept identifies a species as a set of actually or potentially interbreeding organisms. This is generally the most useful formulation for scientists working with living examples of the higher taxa like mammals, fish, and birds, but meaningless for organisms that do not reproduce sexually. It distinguishes between the theoretical possibility of interbreeding and the actual likelihood of gene flow between populations. For example, it is possible to cross a horse with a donkey and produce offspring, however they remain separate species—in this case for two different reasons: first because horses and donkeys do not normally interbreed in the wild, and second because the fruit of the union is rarely fertile. The key to defining a biological species is that there is no significant cross-flow of genetic material between the two populations.

Answers.com (http://www.answers.com/species&r=67)

Oops! Already said and now I can't delete this. #-o
I'll leave it here.

Captain Kidd
2005-Apr-20, 04:53 PM
Humans share 99% of the same DNA as chimps. Will a geneticist one day decide to try and fertilize chimp eggs with human sperm (or the opposite) - just to see if fertilization happens?
Considering how hairy some of the guys running around in muscle shirts are, I think they've already tried and suceeded.

SeanF
2005-Apr-20, 04:58 PM
Can we bring back Mastadonts by using an elephant and mastadont DNA recovered from a frozen mastadont?
Apparently, some folks think so (http://www.badastronomy.com/phpBB/posting.php?mode=quote&p=457860&) (okay, so that's a mammoth as opposed to a mastodon).


Humans share 99% of the same DNA as chimps. Will a geneticist one day decide to try and fertilize chimp eggs with human sperm (or the opposite) - just to see if fertilization happens?
Supposedly this has been tried, both in the US (in the '20s) and in China (around 1970). Emphasis, as noted, on the "supposedly." :)

Swift
2005-Apr-20, 06:19 PM
Humans share 99% of the same DNA as chimps. Will a geneticist one day decide to try and fertilize chimp eggs with human sperm (or the opposite) - just to see if fertilization happens?
Supposedly this has been tried, both in the US (in the '20s) and in China (around 1970). Emphasis, as noted, on the "supposedly." :)
I wasn't familiar with this earlier work. My impression is that even if it was tried, biologists have gotten much better at in-vitro fertilization in the last 10-20 years. I am actually rather surprised that this has not been tried and would not be surprised to learn it was attempted but the results were not published for moral reasons. I also would be surprised if the attempt did not at least result in a living zygote or embryo.

Disinfo Agent
2005-Apr-20, 06:21 PM
What would be the point of making such a hybrid? :-?

GeorgeLeRoyTirebiter
2005-Apr-20, 06:21 PM
An examination of the American Ornithologists’ Union’s checklists over the past few decades will show that it is difficult to apply a rigid taxanomical structure to dynamic living organisms. Over the years, species have been lumped together (Dark-Eyed Junco), species have been split apart (Rufous-Sided Towhee), and some carefully considered decisions have been reversed in the face of new evidence (the temporary lumping of the Baltimore and Bullock’s Orioles). For a time they threw up their hands in frustration and simply gave up trying to classify the finch-like birds (finches, cardinals, New World sparrows) and dumped them all into the family Fringillidae. Fortunately, DNA-DNA hybridization was developed, although this has caused plenty of new debates. Even if punctuated equilibrium is true, speciation is still a gradual process. Every living thing is currently undergoing this process, so the best biologists can do is try to decide on the arbitrary points where one species ends and another begins.

George
2005-Apr-20, 08:16 PM
I thought they were both Pike?
Nope, different species. The Northern Pike is Esox lucius, while the Muskellunge is E. masquinongy.
Thanks.



The interesting-sounding species name is simply Ojibwa for "Ugly fish".

Can anyone guess where I'm from? :wink:
I only know St. Paul and Ely. Sorry. :oops:

the_shaggy_one
2005-Apr-20, 08:45 PM
Minnesota would have been an acceptable answer. I actually spend thanksgivings up in Ely, but I live in the SW suburbs of Minneapolis. There are about 10 lakes within 5 miles of my house... :P

George
2005-Apr-20, 09:02 PM
Minnesota would have been an acceptable answer. I actually spend thanksgivings up in Ely, but I live in the SW suburbs of Minneapolis. There are about 10 lakes within 5 miles of my house... :P
Ely is where I learned to water ski (behind a 10 hp John boat. I was skinny and light enough to finally get up. I have great memories of my canoeing as a teenager up on your border.

ChesleyFan
2005-Apr-20, 09:56 PM
If I remember, Lions and Tigers can also procreate... snip

Yeah. They're, like, my favorite animal. Bred for their skills in magic.

BAroxMysox
2005-Apr-20, 10:16 PM
I beat one up with my bo-staff. :P