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Author Topic:   On Transitional Species (SUMMATION MESSAGES ONLY)
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 24 of 314 (505187)
04-08-2009 4:28 PM
Reply to: Message 16 by pandion
04-07-2009 7:41 PM


Transitional Semantics
Hi, Pandion.
Welcome to EvC!
pandion writes:
And while it would be silly to claim that T. rex is ancestral to birds, it is transitional between the Saurischia and the later Maniraptora (like the Dromaeosauridae). Again there is a mix of early traits and derived traits (like feathers). But they are not ancestral to birds. They share a common ancestor with birds.
I rather agree with Kuresu. You could say that a certain intermediate characteristic of T. rex is transitional between the homologous characteristic in plesiomorphic Saurischia and the homologous characteristic in Maniraptora, but to label T. rex as a transitional fossil between the two does carry with it the connotation of ancestry.
I don't know the phylogenetic relationshps within Saurischia very well, but if the Maniraptora are thought to have evolved from within the Coelurosauria, then you could call the Coelurosauria a transitional clade. But you can't really justify calling all individual coelurosaurians transitional. This is largely because the fossil record of theropods is relatively complete: in a group with only two or three known species, usage of the term "transitional" is (expectedly) less rigid.
For most transitional fossils, such as Archaeopteryx, much of the detailed phylogeny is unknown, so we call it transitional, not because it is definitely the ancestor of all birds itself, but because it is the only known member of a group that we are quite certain is transitional.
The same goes with Schinderhannes, the "transitional" proto-arthropod: it lived in the Devonian period, but true arthropods, which are thought to be derived from Schinderhannes's clade, were already abundant in teh Cambrian. But, since Schinderhannes is the only known representative of the clade that bridges the gap between Dinocarida/Anomalocarida and Arthropoda, we call it "transitional." If we had a better fossil history than we do, we would likely not refer to Schinderhannes as transitional (although we would still consider the large clade containing it to be transitional).
-----
I think the word "transitional" is heavily reliant on context for meaning, which is why creationists have had such a heyday making all kinds of ludicrous claims about it.
-----
For Kuresu: if you put the dBCode "code" around your diagrams, it preserves your spacing, so your dendrograms will come out looking like dendrograms instead of left-justified text.

-Bluejay/Mantis/Thylacosmilus
Darwin loves you.

This message is a reply to:
 Message 16 by pandion, posted 04-07-2009 7:41 PM pandion has replied

Replies to this message:
 Message 26 by pandion, posted 04-09-2009 2:54 AM Blue Jay has replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 27 of 314 (505288)
04-09-2009 8:08 PM
Reply to: Message 26 by pandion
04-09-2009 2:54 AM


Re: Transitional Semantics
Hi, Pandion.
pandion writes:
bluejay writes:
I rather agree with Kuresu. You could say that a certain intermediate characteristic of T. rex is transitional between the homologous characteristic in plesiomorphic Saurischia and the homologous characteristic in Maniraptora, but to label T. rex as a transitional fossil between the two does carry with it the connotation of ancestry.
Duh. My point was that T. rex was not ancestral to birds and I made no implication that it was. I'm not sure what you read, but it wasn't my post.
Perhaps you thought I wrote "...to label T. rex as a transitional fossil does not carry with it the connotation of ancestry"? Please notice that the word "not" does not appear in that sentence: I was, in fact, stating the exact opposite of your stance on the issue.
Duh.
-----
pandion writes:
Bluejay writes:
I don't know the phylogenetic relationshps within Saurischia very well, but if the Maniraptora are thought to have evolved from within the Coelurosauria, then you could call the Coelurosauria a transitional clade.
Indeed you could, and in fact it is so. In fact, that's what I said.
Since the literary technique of juxtaposition is apparently lost on you, let me explain it for you. The only reason I included the sentence you quoted there was to allow you the opportunity to compare it to the sentence that follows, which I’ve copied to here:
Bluejay, post 24, writes:
But you can't really justify calling all individual coelurosaurians transitional.
Juxtaposition is a method of clarification: it places a correct statement beside an incorrect statement so the reader can clearly see the difference between the two. The two sentences were meant to be read together.
-----
pandion writes:
Bluejay writes:
you can't really justify calling all individual coelurosaurians transitional.
Why not? Do they not all have both primitive and derived traits?
This comment also obviously stems from your misreading of my first sentence. I do not agree with you that your definition of transitional is entirely appropriate, and my entire post was an attempt to explain why.
-----
pandion writes:
Bluejay writes:
This is largely because the fossil record of theropods is relatively complete:
Tell me another one. That one was hilarious.
Is there a particular reason why you chose to skip the word relatively when reading my statement? This is another literary technique called contextual cues, whereby a writer inserts a few extra words around the word in question to denote the scope of the statement being made. In this case, the word relatively indicates that the writer is not stating that the fossil record of theropods is complete, but that it is more complete than other fossil groups. In the absence of a direct reference, it’s common practice to assume that the writer is comparing the subject of the sentence to something else within the discussion.
So, what fossil groups do I reference in my post? What other fossil groups are being discussed on this thread? Would you not agree that, of all the fossil groups that have so far come up in this discussion, the Theropoda indeed have the most complete fossil record? So, I would ask that you kindly refrain from your juvenile humor until after you have taken a couple technical writing courses.
Since reading is apparently not your strong suit, I fear that the rest of this post may be all in vain, but, being a stubborn and optimistic person, I will proceed anyway.
-----
Since my last angle of attack failed, let me try a simpler approach:
Notice that the word species is a phylogenetic term. Therefore, usage of this term implies phylogeny. Thus, usage of the term transitional species also implies phylogeny. If your intention is not to convey phylogeny, then you should avoid using terms that are loaded with a phylogenetic meaning.
That’s why I said you could consider T. rex’s character state transitional, but not the species itself.
But, frankly, I’m tired of debates about what terms mean. As such, this is likely my last post on the meaning of transitional species.
Edited by Bluejay, : I felt that the "duh" was appropriate.

-Bluejay/Mantis/Thylacosmilus
Darwin loves you.

This message is a reply to:
 Message 26 by pandion, posted 04-09-2009 2:54 AM pandion has replied

Replies to this message:
 Message 28 by pandion, posted 04-10-2009 8:39 AM Blue Jay has not replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 74 of 314 (508102)
05-10-2009 4:33 PM
Reply to: Message 72 by Trev777
05-10-2009 3:51 PM


Re: THOSE FINCHES
Hi, Trev.
And, Welcome to EvC!
You've provided some great material for a discussion there. I rather disagree with a large portion of your argument (particularly with the insinuation that evolutionists would "lose faith" if they learned that Darwin was wrong about something).
However, I don't think Darwin's finches are part of the intended topic of this thread.
If you would like to discuss Darwin's finches, you can start a new thread in the "Proposed New Topics" forum (here); or I could do so for you, if you'd like: I (and I'm sure many others) would be interested in discussing it with you.
Have fun at EvC!

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 72 by Trev777, posted 05-10-2009 3:51 PM Trev777 has not replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 119 of 314 (517439)
07-31-2009 8:07 PM


Bump for Alan Clarke
This post is a reply for Alan Clarke's Message 97, on the thread "Evolutionary Theory Explains Diversity," where it is off-topic. Since this thread's original discussion has run its course, I propose that, if Alan wishes to continue his discussion about transitional fossils, he be allowed to do so here.
Alan presented the following image as evidence that coelacanths and tetrapods are not related. Aside from the fact that he is attacking a 71-year-old argument (by his own admission) that is not considered valid by anybody he's trying to convince (again, by his own acknowledgement); Alan is also apparently only privy to partial evidence.
He presented this image:
I would like his opinion on this image:
Note that Tiktaalik's limb fits nicely between the limb of a lobe-finned fish and the limb of a tetrapod.
Also note that Tiktaalik's arm bones are attached to the ribcage (by means of a shoulder blade, no less), as are the arm bones of its predecessor, Panderichthys (whose shoulder blades are smaller and thinner than Tiktaalik's).

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 147 of 314 (605823)
02-22-2011 11:13 AM
Reply to: Message 142 by Robert Byers
02-21-2011 10:07 PM


Bugs to Buffaloes
Hi, Robert.
Robert Byers writes:
Anyways it unreasonable to say massive biology change took place from bugs to buffalos and there not be heaps of pieces of all or most or some or a great deal of the intermediate stages.
I strongly urge you (and all creationists in general) to get away from the alliterated/rhymed "from X to Y" evolution caricatures: despite the delightful symmetry of the literary device, buffalo did not evolve from bugs, and you're not impressing anybody with your ability to find two organisms that start with the same letter.
Snowclones rank among the least original and least clever literary devices, even when alliterated or rhymed: yet you people throw them around as if they're not only literary gold, but also of merit in a science debate.

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 142 by Robert Byers, posted 02-21-2011 10:07 PM Robert Byers has not replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 178 of 314 (606795)
02-28-2011 12:11 PM
Reply to: Message 173 by Robert Byers
02-28-2011 4:33 AM


Re: Exceptio Probat Regulam
Hi, Robert.
Robert Byers writes:
If evolution was true then there should be millions of remnants leftover in the anatomy of creatures without practical use.
I think there's something I can add here that won't be redundant to what others have said.
Let's think logically about how we would expect evolution to happen.
If an organism needs to adapt to a new environment, what do you think is the most likely way of doing this?
Would it be more likely that the organism would abandon old traits and take on new ones, or that the organism would keep existing traits and modify them for the new environment?
For instance, if a certain animal was moving from a grassland to a forest, would you expect it to simply abandon its old grass-eating stomach and grow a new, tree-eating stomach?
Or, would you expect it to simply use the grass-eating stomach to eat trees, and modify it as needed?
How about for a fish coming out of the water? Those fins are useless on land, so should the fish lose them and grow some legs? Or, should the fish use the fins on land and modify them as needed?
How about a predator whose prey adapts to run faster? Should the predator lose its retractable, prey-grabbing claws and grow some speed-adapted hooves instead? Or, should the predator use its claws for running and modify them as needed?
If you landed on an uninhabited island in an airplane, but needed a car on the island, would you simply modify the airplane's engine, or would you throw out the airplane engine and make a new car engine to replace it?
By far, the most practical strategy is to not make new parts and abandon old ones, but to simply modify the old parts to the new requirements. This is because most structures can be used for multiple purposes. This means that there is usually little need to grow new things and lose old things, because old things can be modified to serve new purposes.
So, given that modification, rather than wholesale abandonment and reconstruction, is a much more efficient strategy, we would expect evolution to follow the "modification" pathway a lot more often than it follows the "wholesale abandonment and reconstruction" pathway.
So, under an evolutionary model, we should expect to observe a lot more instances of modified parts than of abandoned parts.
Doesn't this seem reasonable?

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 173 by Robert Byers, posted 02-28-2011 4:33 AM Robert Byers has replied

Replies to this message:
 Message 196 by Robert Byers, posted 03-03-2011 2:39 AM Blue Jay has replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


(1)
Message 228 of 314 (607835)
03-07-2011 11:55 AM
Reply to: Message 196 by Robert Byers
03-03-2011 2:39 AM


Re: Exceptio Probat Regulam
Hi, Robert.
Robert Byers writes:
they use marine mammal vestigial bits as AHA evidence that evolution occurred in a important way. In using this evidence they must be consistent.
Detective (on witness stand): We found evidence that this woman was shot by the defendant.
Attorney: But, you also found evidence that that other woman was stabbed by the defendant?
Detective: Yes, that's correct. He shot one person, and stabbed someone else.
Attorney: I admit that you have pretty good evidence that he stabbed that other woman. But, doesn't the fact that he didn't stab this woman show that he isn't a murderer?
Detective: I don't understand the question.
Judge: Please rephrase.
Attorney: You declared stab wounds with his fingerprints to be evidence that he is a murderer. So, doesn't this mean that the lack of a stab wound on this woman is evidence that he is not a murderer?
Detective: Um... no. I didn't actually say that. I mean, yeah, that woman was stabbed and this woman was shot, but the evidence still points to the same guy having killed them both.
Attorney: You fired first on Fort Sumter, Detective. Now, you must be consistent with that evidence: if stab wounds are evidence that my client is a murderer, than the noticeable scarcity of stab wounds when we look at all his alleged victims is surely evidence that he is not a murderer, right?
Detective: But... stab wounds aren't the only evidence. There's fingerprints, gunshot res---
Attorney: Once you've retreated to the line that the shooting is a special case, you can no longer use it as evidence that my client is a murderer!
Detective: Was there a question in there?
-----
Robert Byers writes:
if you use vestigial bits to make a conclusion then the opposite conclusion is better made by the fantastic poverty of vestigial points.
I don't know how they do things in Canada, but I distinctly remember being thoroughly taught the concept of opposites throughout my primary education in the United States. So much so, in fact, I feel qualified to teach it to you. Watch:
The opposite of "existent" is "non-existent."
The opposite of "few" ("paucity") is "many" ("abundance").
Our conclusion: evolution
Opposite conclusion: not evolution.
Our evidence: existence of vestigial parts.
Opposite evidence: non-existence of vestigial parts.
Do you see how "there are few vestigial parts" is not the opposite of "vestigial parts exist"?

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 196 by Robert Byers, posted 03-03-2011 2:39 AM Robert Byers has not replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 241 of 314 (607993)
03-08-2011 9:22 AM
Reply to: Message 233 by Robert Byers
03-08-2011 4:45 AM


Re: Exceptio Probat Regulam
Hi, Robert.
Robert Byers writes:
bluescat48 writes:
Primates, Rodentia & Lagomorpha are in one sub class whereas Bats (2 orders) Megachiroptera & Microchiroptera together with the Insectivora, Cetartiodactyla, Perissodactyla, Carnivora & Pholidota are in the subclass Lauasiatheria
This creationist sees bats as just rodents...
Bluescat is right, Robert: bats are more closely related to horses, tigers, whales and pangolins than to rodents.
You can visualize bats however you want, but reality is stubbornly defying your opinion right now. Don't let that stop you, though: maybe, if you're insistent enough, reality will eventually give in to the infallible logic of your demands and make bats into flying rodents.

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 233 by Robert Byers, posted 03-08-2011 4:45 AM Robert Byers has not replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 248 of 314 (608067)
03-08-2011 2:51 PM
Reply to: Message 246 by Taq
03-08-2011 11:42 AM


"Radar Genes"
Hi, Taq.
Actually, Robert's right about "radar genes" (if, by "radar genes," you mean, "one gene whose protein product is involved in sonar").
This is what Robert is talking about. Here is another article (from Science).
To summarize: there is a protein in mammalian ears called prestin, which is involved in processing high-frequency sound. While the sequence of the gene for prestin varies widely across mammals, it is virtually identical in bats and dolphins (although, the Science article clarifies that it's only the functional parts of the protein that are identical), and the researchers have hypothesized that the same sequence of mutations occurred in both.
I haven't read very far into it yet. However, if the sequence for the gene for prestin actually were identical in bats and dolphins (which apparently doesn't seem to be the case), then I would personally be obliged to regard it as evidence for some (small) measure of "tinkering" design, simply because it would violate the nested hierarchy that serves as one of our favorite evidences for evolution.

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 246 by Taq, posted 03-08-2011 11:42 AM Taq has replied

Replies to this message:
 Message 249 by RAZD, posted 03-08-2011 3:56 PM Blue Jay has seen this message but not replied
 Message 250 by Taq, posted 03-08-2011 4:06 PM Blue Jay has seen this message but not replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 284 of 314 (609083)
03-16-2011 1:39 PM
Reply to: Message 275 by Robert Byers
03-16-2011 2:42 AM


Antadillo?
Hi, Robert.
Robert Byers writes:
Time is essential for the claims of evolution turing a ant into a armidillo.
Good grief, Robert: armadillos did not evolve from ants.
Evolution does not make any claims about ants turning into armadillos.
Stop picking your examples based on what letter of the alphabet they start with!
But, if you absolutely have to pick specific "simple" and "complex" animals for future examples, please bear in mind the fact that insects are considered one of the most complex types of animals.

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 275 by Robert Byers, posted 03-16-2011 2:42 AM Robert Byers has not replied

Replies to this message:
 Message 285 by arachnophilia, posted 03-16-2011 1:57 PM Blue Jay has seen this message but not replied

  
Blue Jay
Member (Idle past 2698 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 312 of 314 (610390)
03-29-2011 2:08 PM


Word Games
I was debating with myself for a while about whether I'd spent enough time with this thread to allow me to post a summation, but then I figured that it wouldn't hurt anybody.
Here's how I see it:
The arguments brought by Robert Byers are simply about words: biological organisms can leave geological evidence. We can learn considerably more about biology by studying this geological evidence than Robert seems to believe.
The only reason to insist that biology and geology must be neatly partitioned into their separate spheres of influence is simply one of semantics: that's how humans define the terms, so that's how it must be.
Consider this argument: Books are not humans, yet they can tell us a lot about humans. Should we reject all of our knowledge about humans that is derived from the written word simply because the written word is not human?
Books certainly also aren't God, so shouldn't Robert also exclude books as evidence of God?
No, no: paper and print is perfectly legitimate as evidence about things that are not paper and print. However, biologists are forbidden from using anything that is not alive as evidence about things that are alive.
What a waste of the thread: I like talking about transitional fossils.

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

  
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