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On 8/11/2006 07:49:00 PM, waxed damned near poetic whilst opining...
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I'm sure you're right. I can't tell you how many times I've seen Davison do something outrageous and thought "that old monkeyfucker!"
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On 8/11/2006 07:53:00 PM, JanieBelle waxed damned near poetic whilst opining...
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Well I'm glad it's not just me, Arden.
Nice to see you around!
Kisses,
JanieBelle
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On 8/12/2006 04:23:00 AM, Alan Fox waxed damned near poetic whilst opining...
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I just posted a comment at UD pointing out the arbitrary distinction between gene and chromosome that John makes. I need to start winding him up for his banning on the 28th August. I have my post in preparation.
Salut les filles
PS French keyboard is AZERTY layout whilst French Canadian is QWERTY, so is easier for bilingual use
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On 8/12/2006 05:14:00 AM, Lifewish waxed damned near poetic whilst opining...
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Worryingly, to me at least, everything between "Josef Goebbels..." and "...(Mendelian) level anyway" seems broadly accurate. Is that just my naivety talking?
Incidentally, for Janie's sake, I should mention that he's wrong about species being strictly definable. Quite often, some members of apparently different species can interbreed but others can't. Quite often it's effectively random as to whether any offspring are sterile.
The ultimate example of this is ring species. These are species that, for one reason or another, have gradually spread in a large arc. An example of this is a particular type of gull, which, over the years, has spread right the way round the arctic circle.
In different places this gull comes in different varieties (note: "variety" is the next level below "species"). It is called, in sequence, the Herring Gull, American Herring Gull, Vega Herring Gull, Birula's Gull, Heuglin's Gull, Siberian Lesser Black-Backed Gull and Lesser Black-Backed Gull. That list takes us from Britain, through North America, right round Russia and into Norway.
Now comes the fun part. Each gull variety can demonstrably breed with the variety next door to it. Herring gulls can breed with American herring gulls, which can breed with Vega herring gulls and so on. But the original herring gull cannot breed with the lesser black-backed gull! In the time it takes genetic material to flow right around the arctic, it gets sufficiently mangled as to make interbreeding impossible.
So, do we classify this as one species or two? If we didn't know about the existence of all the other gull varieties, we'd undoubtedly class the herring gull and lesser black-backed gull as being two distinct species. But having the other varieties makes the situation far more complex - if you're going to split the gull population into two species, you're gonna have to draw an effectively arbitrary dividing line. Do we draw that line in America? Somewhere in Siberia, maybe. How about the Atlantic?
Problems like ring species give taxonomists severe headaches. If JAD has a simple solution to all these complexities, he'll make a lot of people very happy. Sadly, his views on this subject appear to be sufficiently simplistic that this is decidedly unlikely.
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On 8/12/2006 08:47:00 AM, Zachriel waxed damned near poetic whilst opining...
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Originally, species were considered distinct and hybrids "endowed with sterility, in order to prevent their confusion."
But Darwin developed evidence, from a number of sources, that such the separation between species and sterility of hybrids is gradual and not absolute. This continuum is of such fundamental importance to his theory that he devotes an entire chapter (IX) of Origin of Species to the subject.
Many people do not realize how well-reasoned and careful Darwin was in his scientific work. It's dated, of course, but still considered a great opus in scientific reasoning. Try reading just a few chapter descriptions from Origin of Species. (We won't talk about the eight years he spent just studying barnacles.)
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On 8/12/2006 08:47:00 AM, JanieBelle waxed damned near poetic whilst opining...
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I just posted a comment at UD pointing out the arbitrary distinction between gene and chromosome that John makes. I need to start winding him up for his banning on the 28th August. I have my post in preparation.
Actually we've altered the rules a bit to give away two posts, so you'd win TWO posts if he got the boot that particular day. You'll still win one if he gets it any other day between August 21st and October 30th.
Here's the link for the updated rules.
French keyboard is AZERTY layout whilst French Canadian is QWERTY, so is easier for bilingual use
See? Learn something new every day at UDOJ! (For those not following Alan's comment, it was in response to this question I asked Alan, regarding why he used a French Canadian keyboard.)
Cherchez les femmes! Elles aiment embrasser!
JanieBelle and Kate
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On 8/12/2006 08:54:00 AM, JanieBelle waxed damned near poetic whilst opining...
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Worryingly, to me at least, everything between "Josef Goebbels..." and "...(Mendelian) level anyway" seems broadly accurate. Is that just my naivety talking?
Perhaps. I can't give an educated opinion on that. I was taking aim more at everything outside that block, which seemed to imply his advocacy of testing all that "up close and personal", if you know what I mean, and I think you do!
I kill me.
As for species, I was sort of getting the impression that "species" was a rather vague and arbitrary imposition of human linguistics. Much like "planet".
Seems like the universe doesn't tend to do things in neat little catagories, more like in a continuum. Catagories are more of a human invention. Your comment would seem to agree with that assesment.
Am I on track with that here?
Kisses,
JanieBelle
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On 8/12/2006 08:57:00 AM, Zachriel waxed damned near poetic whilst opining...
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Zachriel: the separation between species and sterility of hybrids is gradual and not absolute
Um, Davison is somewhat dated on his evidence. He used a specific definition of speciation having to do with reproductive isolation that was important in a specific laboratory situation, but not universally applicable.
Mechanisms of reproductive isolation have been observed both in nature and in the lab. In nature, they are usually due to isolation of populations that diverge over time. But it can also occur due to hybridization or spontaneous polyploidalism (esp. in plants). In flies and orchids, it can occur due to rapid changes in their sex organs.
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On 8/12/2006 09:01:00 AM, JanieBelle waxed damned near poetic whilst opining...
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But Darwin developed evidence, from a number of sources, that such the separation between species and sterility of hybrids is gradual and not absolute. This continuum is of such fundamental importance to his theory that he devotes an entire chapter (IX) of Origin of Species to the subject.
So it would seem that you are in agreement with my last comment, is that correct?
See, you guys are learnin' me somethin'!
Try reading just a few chapter descriptions from Origin of Species.
Actually, Kate just gave me my own hardbound copy, and I intend to take it with me to England for those "down times".
It would be an appropriate time to begin reading it, don't you think?
Kisses to Zachriel, for all his hard work in "dumbing down" the science for me.
JanieBelle
P.S. for your next comment which posted whilst I was writing this...
Um, Davison is somewhat dated
You probably could have just put the period right there.
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On 8/12/2006 09:08:00 AM, Zachriel waxed damned near poetic whilst opining...
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JanieBelle: "As for species, I was sort of getting the impression that "species" was a rather vague and arbitrary imposition of human linguistics. Much like 'planet'."
The distinction between planet and planetoid can be rather arbitrary, but planets are real objects nonetheless.
Species does generally refer to an interbreeding population, which may very well have fuzzy edges, but it is still a real concept with empirical consequences. This is as opposed to higher taxonimic categories, such as order and kingdom, which are arbitrary divisions in the nested hierarchy. The branches of the tree are real, but where to draw the line between 'big' branch and 'small' branch is largely based on historical classifications.
The reason I point this out is because most biologists would reject the claim that species is not a 'real' concept. Just one with fuzzy or chaotic borders. In plants, though, some scientists do reject the species concept due to the vast amount of hybridization between populations. Those crazy botanists and their flowers. And in bacteria, the definition doesn't make much sense as they reproduce asexually.
JanieBelle: "Seems like the universe doesn't tend to do things in neat little catagories ..."
Ain't it the truth.
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On 8/12/2006 09:12:00 AM, DaveScot waxed damned near poetic whilst opining...
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lifewish
What procedures were undertaken to determine beyond a reasonable doubt the two (ring species) gull varieties could not interbreed to produce fertile offspring? As Davison said, artificial insemination is prerequisite to making a determination.
Hybrid infertility isn't black and white either. It's a diminishing probability with greater genetic separation. So the other thing that needs to be done aside from artificial insemination is to use a large number trials to ensure that fertile hybrids are at least very improbable.
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On 8/12/2006 09:26:00 AM, Zachriel waxed damned near poetic whilst opining...
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DaveScot: "As Davison said, artificial insemination is prerequisite to making a determination."
The applicability of ring species to theories of speciation does not require complete reproductive isolation on the ends of the ring. In fact, that is not what would be expected. As there is still gene-flow, the ends of the ring are not reproductively isolated. But most of that gene-flow occurs through the ring and not between its ends. This is what would be predicted by theories of allopatric speciation.
I already noted that speciation can occur in orchids due to rapid changes in their sex organs (and rapid coevolution with their pollenating insect partners). We can also observe reproductive isolation in other species when they refuse to breed with closely related populations. For instance, though tigers and lions may interbreed in captivity, they remain distinct populations in the wild, have different behavioral paterns, and there is no evidence of significant gene flow between the populations. Artificial insemination might give clues, but is certainly not required to indicate reproductive isolation.
Again, speciation is a process, and species boundaries represent a gradation of isolation. And that is what is observed.
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On 8/12/2006 09:39:00 AM, Zachriel waxed damned near poetic whilst opining...
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Zachriel: Um, Davison is somewhat dated.
JanieBelle: "You probably could have just put the period right there."
Ha!
Stay safe on your travels. Are you blogging from overseas?
I hope you clicked to link to "Ain't it the Truth" and listened to one of the great motivational speeches of all time.
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On 8/12/2006 09:45:00 AM, Zachriel waxed damned near poetic whilst opining...
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DaveScot: "So the other thing that needs to be done aside from artificial insemination is to use a large number trials to ensure that fertile hybrids are at least very improbable."
This actually sort of gets at the point. We would expect differing degrees of reproductive isolation. "Very improbable"? Or just "somewhat improbable" or simply "less likely" than a typical population. Or perhaps differing degrees of isolation in differing circumstances.
As Darwin noted, "Sterility various in degree".
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On 8/12/2006 09:57:00 AM, JanieBelle waxed damned near poetic whilst opining...
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Stay safe on your travels. Are you blogging from overseas?
Of course!... assuming of course that the airline folks don't break the laptop in the checked baggage.
I hope you clicked to link to "Ain't it the Truth" and listened to one of the great motivational speeches of all time.
That's a great speech, and it's from one of my all time favorite movies. That one, and the original "Willie Wonka" are right up near the top. With very few exceptions, they just don't make movies like the old ones. At Christmas time every year we watch "It's A Wonderful Life" with Jimmy Stewart. He had such a great voice.
I think Braveheart and The Matrix are on the top ten list, though. I enjoyed Johnny Depp in Pirates, but his Wonka just didn't carry as well as Wilder's. It was respectable, and he didn't try to just do "Johnny Depp does Gene Wilder does Willie Wonka", which is commendable, but some perfomances just can't be equalled I suppose.
Kate Hepburn was really wonderful in On Golden Pond. That's one of my Mom's favorites. The world is a lesser place for her loss.
Ok, I'm done meandering down Hollywood's walk of fame. I have stuff to take car of, not the least of which is getting my hair done.
Back Later,
JanieBelle
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On 8/12/2006 10:37:00 AM, waxed damned near poetic whilst opining...
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Try reading just a few chapter descriptions from Origin of Species.
Actually, Kate just gave me my own hardbound copy, and I intend to take it with me to England for those "down times".
Careful, I'm told that book turns people into atheist Communists who hate the American family. :-)
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On 8/12/2006 11:00:00 AM, Lifewish waxed damned near poetic whilst opining...
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As Davison said, artificial insemination is prerequisite to making a determination.
My understand is that, traditionally, species are based not on whether members of each can interbreed, but on whether they in fact do interbreed. The alternative, as you suggest, would be inordinately expensive in terms of time and resources, especially for large or hard-to-breed species. It would also be verging on the irrelevant - to all intents and purposes, "can breed but doesn't" is indistinguishable from "can't breed at all".
With respect to the gull example, I may have made a bad choice of case study. For reasons that are quite frankly beyond me, at least one group of scientists is claiming that the gulls are not a ring species after all. Incidentally, if anyone can figure out what the linked paper is saying, I'd appreciate an explanation.
As such, I'll propose another example: the Ensatina eschscholtzi salamander. I managed to track down this paper, which apparently provides a thorough discussion of why it's valid to say that the ends of the ring don't hybridise. Haven't had time to read it yet, though.
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On 8/12/2006 11:56:00 AM, waxed damned near poetic whilst opining...
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With respect to the gull example, I may have made a bad choice of case study. For reasons that are quite frankly beyond me, at least one group of scientists is claiming that the gulls are not a ring species after all. Incidentally, if anyone can figure out what the linked paper is saying, I'd appreciate an explanation.
Sadly, I couldn't follow the middle third of that abstract at all. Argh. :-(
It's interesting how the ring species concept has an exact analog in language and dialect spread over geographic space. One constantly sees situations where the far ends of a language's area consists of dialects that are not mutually intelligible, yet along the spread, at no point are any two adjacent dialects unintelligible. Until recently, most of the Romance language family worked that way.
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On 8/12/2006 12:30:00 PM, Zachriel waxed damned near poetic whilst opining...
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lifewish: " For reasons that are quite frankly beyond me, at least one group of scientists is claiming that the gulls are not a ring species after all."
A ring species is characterized by gradual change along a geographic area, with the geographic area forming a ring. The scientists used genetic data to show that, though the birds evolved from a common ancestor, they don't change gradually along a geographical gradient. Being gift with flight, birds sometimes happened to migrate great distances and started new colonies. This created a complex geographical distribution, not a simple ring.
However, this complexity is completely compatible with allopatric speciation. Just not a gradual change over distance.
At this point, I believe a cite to expert opinion is in order: JanieBelle: "Seems like the universe doesn't tend to do things in neat little categories ..."
JanieBelle: "It would be an appropriate time to begin reading it, don't you think?"
Hopefully, you'll be having too much fun. But for a rainy day, perhaps. (Keep in mind that it is somewhat dated, and Darwin wrote it not for the lay public, but to convince his scientific peers.)
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On 8/12/2006 05:51:00 PM, waxed damned near poetic whilst opining...
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Not with any intent to hijack but the planet question is fascinating.
NPR Story
vino
Hi vino! I think I have the template squared away enough, and with Lifewish's tweaks of the new "Recent Comments" script, you shouldn't have to break up your links anymore. Feel free to try one or two without the underscores, and we'll see what happens. Thanks for the link. I've only got a sec to poke my head in, so if it breaks something, I'll fix it when I can, but I don't think it will. Kisses, jb
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On 8/12/2006 07:13:00 PM, waxed damned near poetic whilst opining...
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Or I could just learn how to do tags properly in blogger. I do okay at PT and ATBC but the first time I did one here it didn't work properly and there are no apparent instructions.
Anyway. Here is a triplet about species I rather like. You can get something out of them without a grad degree necessary.
Species is as Species does part I
Species is as Species does part II
Species is as Species does part III
Don't worry, they are that long.
And from the same place is a really cool vid of a shark getting his from an ???
DaveScot,
As for your snark, I'm sure you have the wherewithal to find the original work that led to the species conclusions. If you want to find fault with the methodology of the original researchers, take it up with the biologists who peer reviewed the work. I'm sure they would love to know how you don't think their critical analysis was up to snuff.
ciao, vino
PS,
I did something halfway smart and looked up the page source. I think I marked this up right.
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On 8/12/2006 09:41:00 PM, Zachriel waxed damned near poetic whilst opining...
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vino: " Here is a triplet about species I rather like."
Excellent articles. With pictures! Thanks.
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On 8/13/2006 08:06:00 AM, JanieBelle waxed damned near poetic whilst opining...
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Cool shark video, vino!
Thanks!
Kisses,
JanieBelle and Kate
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On 8/13/2006 09:23:00 AM, Lifewish waxed damned near poetic whilst opining...
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Ah yes, I was looking round for those articles too but couldn't remember where I'd seen them.
What's quite fun (if you're an incurable geek) is when you try to model this stuff using a computer. As far as I can tell, it actually doesn't take that long for speciation to occur just through random genetic drift, if the populations are sufficiently isolated.
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On 8/18/2006 05:30:00 PM, JohnADavison waxed damned near poetic whilst opining...
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I swear on the Bible that I fucked a chimpanzee, never even thought twice about it, but I've been fucked by some of the biggest dicks that ever surfaced in my asshole on the world wide web. Two in particular stand out. Spravid Dinger, who made me feel like the bitch I truly am, and his Darwimpian counterpart, Falan the Ox, who I enjoy serving as my lord and master, and the man whose bathwater I'd love to drink, Esley Welsberry.
I love my peepee so!
"My past intelligence is undeniable, my present brain undemonstrable."
Dohn Assholeisforthetaking. Javison
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On 8/19/2006 02:04:00 AM, JanieBelle waxed damned near poetic whilst opining...
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I'll take the Big Green Marker to your comment next week when I'm home.
Davison, you've been banned. Go away, you're not welcome here and your comments will be toyed with or deleted at my pleasure. None will stand intact.
Beat it freak show.
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On 8/19/2006 05:17:00 AM, JohnADavison waxed damned near poetic whilst opining...
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You sexy bitch. If you were a man I'd let you take a dump on me but and deny me a response. I have no business running a blog anywhere. Got that? write that down. Take your green marker and exercise with it!
Kisses around my 'taint (I'd do it myself but I'm old and not so flexible anymore)
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On 8/19/2006 01:28:00 PM, JohnADavison waxed damned near poetic whilst opining...
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I bet I are at least 50 pounds overweight and I want it all in my ass.
Kisses
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On 8/19/2006 11:50:00 PM, JanieBelle waxed damned near poetic whilst opining...
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Javison,
If you were capable of a coherent response, we wouldn't be dumping on you to begin with. You're a psycho. You haven't any sanity left to you.
Whatever dignity your family might retain, you should have the courtesy to protect. Go to the nearest old folks home and check in. Ask the nice man in charge to fit you with one of those sweaters with the backwards arms.
Piss off. I don't come to your single post excuse for a blog and post sanity, don't come here and spray your vomitous filth all over my blog.
You are to be pitied, I suppose, but I haven't even that for you.
Derision, Javison. It's all you get.
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On 8/20/2006 12:28:00 PM, JohnADavison waxed damned near poetic whilst opining...
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Go get yourself liposucked silly. I hear it is rather noisy, slurp slurp. Be sure to green pencil me when you get back to wherever the hell you are away from. God but you are precious!
I love my peepee so!
Kisses
