Register | Sign In


Understanding through Discussion


EvC Forum active members: 65 (9162 total)
4 online now:
Newest Member: popoi
Post Volume: Total: 915,815 Year: 3,072/9,624 Month: 917/1,588 Week: 100/223 Day: 11/17 Hour: 0/0


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   Why is evolution so controversial?
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 24 of 969 (723942)
04-11-2014 2:30 AM
Reply to: Message 1 by Cedre
04-10-2014 4:29 PM


Even more shocking was my biology professor's reply when I asked her to elaborate on some detail of evolution during a class, she told me not to trouble myself with such question that will only distract the lesson, and then she added evolution is contentious anyway. "Evolution is contentious!" From the lips of a research professor!
Sorry, but I have to ask: did you choose your school because it was friendly to your religion or because it was the best rated medical school you could afford and get accepted to?
You must realize that this is anecdotal evidence and does not represent anything more than one class by one teacher in one university\college.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 1 by Cedre, posted 04-10-2014 4:29 PM Cedre has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 25 of 969 (723943)
04-11-2014 3:08 AM
Reply to: Message 8 by Cedre
04-10-2014 7:29 PM


massive misinformation
No new body plans, ... have ever been observed or seen by direct experimentation to come about through alleged evolutionary mechanisms. ...
The process ofevolutioninvolves changes in the composition of hereditary traits, and changes to the frequency of their distributions within breeding populations from generation to generation, in response to ecological challenges and opportunities.
Can you tell me where that says new body plans should happen on demand during your lifetime just to please you? Can you tell me where that says that new body plans must occur at all?
You are confusing what HAS happened with what must happen. Have you seen a new continent form? Do you think plate tectonics is bogus because this has not been observed?
... no information-rich systems, ... have been observed or seen by direct experimentation to come about through alleged evolutionary mechanisms. ...
Please define "information-rich system" so that we can tell what you are claiming. New means of dealing with ecological changes are evolving every day, and this would seem to me to be "information-rich system" evolution - or as close to it as is necessary in biology.
... no complex functional machines have ever been observed or seen by direct experimentation to come about through alleged evolutionary mechanisms. ...
Again ... don't confuse what HAS happened with what must happen ...
The process ofevolutioninvolves changes in the composition of hereditary traits, and changes to the frequency of their distributions within breeding populations from generation to generation, in response to ecological challenges and opportunities.
Can you tell me where that says that "complex functional machines" (whatever that means) must happen on demand during your lifetime just to please you? Again I ask have you seen a continent form? Can you tell me why you think this means that evolution is questionable?
Do you understand that your posts are more indicative of ignorance\undereducation than any real issue with evolution?

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 8 by Cedre, posted 04-10-2014 7:29 PM Cedre has replied

Replies to this message:
 Message 26 by Pressie, posted 04-11-2014 5:03 AM RAZD has seen this message but not replied
 Message 30 by Cedre, posted 04-11-2014 12:03 PM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 90 of 969 (724060)
04-11-2014 9:58 PM
Reply to: Message 30 by Cedre
04-11-2014 12:03 PM


More Confusion
I'm no first rate biologist like yourself, I am a medical student so I can be excused for misunderstanding evolution and for showing some ignorance, and so I invite any corrections were my understanding falters.
Great. Start by discarding everything you think you know about evolution, no matter what the source of that information was.
Then read from dependable sources that don't have any agenda other than teaching biology.
One good source is Evolution 101, a high school level self directed course put out by Berkeley University. There are others, but this is probably the best set up imho.
Having said that, I did a college level basic course on evolution. ...
and what you have said about it leads me to think that it was worse than useless, as it appears that the teacher was not that well informed ...
... As I already pointed out medical school doesn't concentrate on evolution, unfortunately -- I wish it did since I find it a fascinating subject, but I've tried to keep up with what the experts on both sides of the issue are saying.
and I have some trouble with the concept of a high ranking medical program ignoring evolution, especially when it comes to diseases. Treating this years flu with last years inoculations won't take into account how the flu virus has evolved in that time, just for one example.
Another example is that I have lymphoma cancer, I have had chemo therapy 6 or 7 times (I'm losing count), each time it is different chemicals because the cancer evolves to be immune to the last ones. Not understanding this would be fatal.
There are dozens of different phyla of animals, each with its own body plan, and according to Wikipedia a "phyla can be thought of as grouping organisms based on general specialization of body plan", so it goes without saying that new body plans arose to account for the phyla of animals we see around us today. ...
Not quite right.
Phylum - Wikipedia
quote:
In biology, a phylum (/ˈfaɪləm/; plural: phyla)[note 1] is a taxonomic rank below kingdom and above class. Traditionally, in botany the term division is used instead of "phylum", although in 1993 the International Botanical Congress accepted the designation "phylum".[1][2] The kingdom Animalia contains approximately 35 phyla; the kingdom Plantae contains 12 phyla.
Informally, phyla can be thought of as grouping organisms based on general specialization of body plan.[6] At the most basic level, a phylum can be defined in two ways: as a group of organisms with a certain degree of morphological or developmental similarity (the phenetic definition), or a group of organisms with a certain degree of evolutionary relatedness (the phylogenetic definition).[7] Attempting to define a level of the Linnean hierarchy without referring to (evolutionary) relatedness is an unsatisfactory approach, but the phenetic definition is more useful when addressing questions of a morphological naturesuch as how successful different body plans were.
I've bolded your quoted section.
The issue I take with your comments is that the body plans are not completely different, rather they have different specializations of a generally similar body plan.
When we look at human beings we see our classification as:
quote:
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Tribe: Hominini
Genus: Homo
Species: H. sapiens
When we look at mammal skeletons there are many similarities in the order and type of bones -- the upper limbs have one bone, the lower limbs have two bones and the terminal paw/hand/foot/etc has many bones. There are rib bones off the spinal column and the skull is at one end of the spinal column while the tail is at the other. The bones from one mammal can be mapped to the bones of another. This is -- to my mind -- one basic body plan with variations (specializations) in length and thickness and such.
Chordate - Wikipedia
quote:
Chordates are animals possessing a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail for at least some period of their life cycles. Taxonomically, the phylum includes the subphyla Vertebrata, including mammals, fish, amphibians, reptiles, birds; Tunicata, including salps and sea squirts; and Cephalochordata, comprising the lancelets. Members of the phylum Chordata are bilaterally symmetric, deuterostome coelomates, and the vertebrate Chordates display segmentation.
As with mammals, when you look at vertebrates ("mammals, fish, amphibians, reptiles, birds; ...") you find the same general patterns of bones in the skeletons and the bones from one vertebrate can be mapped to the bones of another. This is -- to my mind -- still one basic body plan with different variations (specializations) in length and thickness and such.
When we consider the whole tree of life we can trace these homologies back to common ancestors, and even when we go back to where many of the skeletal bones of mammals and reptiles and birds are missing, there are still common elements that show larger groups of related organisms -- there is no major difference that I can see in body plans beyond the development of specialized adaptations.
Perhaps it is a matter of terminology again.
... so it goes without saying that new body plans arose to account for the phyla of animals we see around us today. ...
Do birds and bats have different body plans or the same body plans with different specializations?
The History of Evolutionary Thought - Understanding Evolution
quote:
The central ideas of evolution are that life has a historyit has changed over timeand that different species share common ancestors.
Here, you can explore how evolutionary change and evolutionary relationships are represented in family trees, how these trees are constructed, and how this knowledge affects biological classification. You will also find a timeline of evolutionary history and information on some specific events in the history of life: human evolution and the origin of life.

All those branches of organisms have spinal columns running from head to tail, with ribs and limbs branching off, but not all are tetrapods and not all tetrapods are mammals, yet they all share many aspects of a general body plan with different adaptations\variations\specializations.
Homologies and analogies - Understanding Evolution
quote:
... We use homologous characterscharacters in different organisms that are similar because they were inherited from a common ancestor that also had that character. An example of homologous characters is the four limbs of tetrapods. Birds, bats, mice, and crocodiles all have four limbs. Sharks and bony fish do not. The ancestor of tetrapods evolved four limbs, and its descendents have inherited that featureso the presence of four limbs is a homology.
Not all characters are homologies. For example, birds and bats both have wings, while mice and crocodiles do not....

Having wings is analogous rather than homologous, however the bones that are used are still homologous, they are just different variations\specializations of the bones used in different adaptations to form the wings.
Without providing any evidence that unguided changes are capable of generating new, viable body plans, you matter of factly declare that at some point in the past, body plans have been generated. ...
But yes, and the evidence is in the parts of the body plans that are shared and how one branch develops generation by generation from that common basis to reach the specialized variation on the general body plans of their ancestors.
Because the variations in body plans are not all new and completely different from anything seen before -- that would be astounding (and not evolution).
... This is the problem we've not observed new body plans and yet we are expected to believe that evolution accounts for body plan ...
Curiously, what we have observe is the fossil record, and the development of the different branches by adaptations of previous forms: at no time is the difference between an organism and the previous generation greater than the difference observed within dogs, and we do see a lot of variations in dogs in the specialization of their various parts.
... morphogenesis... Please!
Indeed, another confusion\conflation ...
Morphogenesis - Wikipedia
quote:
Morphogenesis (from the Greek morph shape and genesis creation, literally, "beginning of the shape") is the biological process that causes an organism to develop its shape. It is one of three fundamental aspects of developmental biology along with the control of cell growth and cellular differentiation.
In other words morphogenesis is the embryological development of the individual organism and not the evolution of the species.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 30 by Cedre, posted 04-11-2014 12:03 PM Cedre has replied

Replies to this message:
 Message 94 by Cedre, posted 04-12-2014 10:06 AM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(3)
Message 195 of 969 (724255)
04-15-2014 11:36 AM
Reply to: Message 192 by Larni
04-15-2014 11:21 AM


Re: Back to earth
I think a valid objection to the cow test is that it is not something that MUST occur if the ToE is false.
Finding it would be problematic, but the ToE could be false and you could still not find the cow.
Nested hierarchies are a prediction of the ToE, so finding fossil or genetic evidence that cannot fit into nested hierarchies would counter the prediction and need to be explained by some other mechanism.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 192 by Larni, posted 04-15-2014 11:21 AM Larni has not replied

Replies to this message:
 Message 196 by Dr Adequate, posted 04-15-2014 11:56 AM RAZD has replied
 Message 198 by NoNukes, posted 04-15-2014 12:28 PM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 217 of 969 (724311)
04-15-2014 9:44 PM
Reply to: Message 94 by Cedre
04-12-2014 10:06 AM


Taxonomy vs Cladistics
Thanks again for your reply RAZD
Thank you for the opportunity to discuss this in greater detail. I always happy to help people that want to learn, including other readers of these posts.
You said:
Start by discarding everything you think you know about evolution, no matter what the source of that information was.
Why on earth should I do that? At least show that everything I know about evolution is false!
Not everything but enough to confuse you. Some of the things you think are about evolution are not, and some are wrong. Better to start all over with a clean slate than to try to tease out the wheat from the chaff in lengthy posts (like this). There are resources available, and if you are truly interested in learning you will pursue studying them.
You said:
and what you have said about it leads me to think that it was worse than useless, as it appears that the teacher was not that well informed ...
Uphold this please! Thanks.
In Message 1 you said:
quote:
Even more shocking was my biology professor's reply when I asked her to elaborate on some detail of evolution during a class, she told me not to trouble myself with such question that will only distract the lesson, and then she added evolution is contentious anyway. "Evolution is contentious!" From the lips of a research professor!
Evolution is only contentious to those who do not understand it and have religious reasons for not accepting it. This is a very very small minority within the scientific crowd (people who use the scientific method to reach conclusions based on evidence and repeated testing).
So if you have someone teaching you that says evolution is contentious then I conclude that she is not well versed in evolution.
Of course she may not have wanted to answer your question because the question was silly (you don't tell us what the question in question was), and you may have misunderstood that your question was contentious ...
You said:
and I have some trouble with the concept of a high ranking medical program ignoring evolution, especially when it comes to diseases. Treating this years flu with last years inoculations won't take into account how the flu virus has evolved in that time, just for one example.
Another example is that I have lymphoma cancer, I have had chemo therapy 6 or 7 times (I'm losing count), each time it is different chemicals because the cancer evolves to be immune to the last ones. Not understanding this would be fatal.
I’m not studying to become a pharmacologist. My job’s to diagnose/treat with available treatments. In any case I already pointed out that although touched upon in Medical School evolution is not given front page and centre treatment.
And your job to diagnose and treat with available treatments will be severely handicapped, imho, without understanding how evolution is involved in the diseases and their resistance to old treatments due to evolution. It would be like trying to walk with your feet tied together ...
You said:
Not quite right.
What’s not quite right about what I said? Are you disputing that phyla are based on body plans? Or is your issue with claim that different body plans evolved at Cambrian explosion and later in the Palaeozoic?
Phyla are (arbitrarily defined) based on inherited characteristics that separate the group from other groups, not on whole body plans, per se. Where one taxonomic level ends and another begins is fairly arbitrary in dividing up the natural history of life on earth. The traits used to identify levels are not whole body plans but specializations of specific parts -- the parts that have evolved on a different path than other organisms.
When speciation occurs one daughter population diverges from another daughter population because they evolve different hereditary traits from their common ancestor population. Descendants of those daughter populations will always be separated by that initial division. This is a process that continues to this day.
Remember that what you originally said was:
Message 30: There are dozens of different phyla of animals, each with its own body plan, and according to Wikipedia a "phyla can be thought of as grouping organisms based on general specialization of body plan", so it goes without saying that new body plans arose to account for the phyla of animals we see around us today. So if a new phylum emerges we can reasonably predict that it would have a unique body plan.
There are two rather major problems with this thinking:
First, "body plan" is a rather clunky and useless term to use in this regard and this is what has caused some of your confusion. Evolution works by modification of previous forms, most traits are inherited from their parent/ancestral population, some are new mutations that may or may not be beneficial. If you select a species at any time in the past and compare it to the parent population and the daughter population, you would likely be hard pressed to document any visible differences in their "body plans" ... only after many generations would you see some difference. In one sense new body plans evolve continually with every speciation, we just haven't seen yet how different they will become.
Based on similarities in inherited traits, different species can be grouped as descended from one daughter population while other species can be grouped as descended from a different daughter population, each descended from a common parent population, and wikipedia would be better to say "phyla (and other classification levels) can be thought of as grouping organisms based on general development and specialization of different inherited traits." New body plans don't pop into existence fully developed, they evolve over many generations of accumulated adaptations, which gets us to the other problem:
Second, a "new phylum" won't "emerge" -- unless a new species appears that is completely unrelated to any known breeding\ancestral population existing today -- because "phylum" is an artifact of the Linnean classification system. This would be like growing a new branch from the center of the trunk of an old tree, a new branch grown from dead wood, that then pierces through the other existing tree rings to reach outside the trunk to be visible as a new branch.
Even if a species were to evolve from some prokaryote bacteria into a multicellular organism that then evolved into something with arms and legs -- over many generations and as an example -- a whole new "body plan" ... it would not become de facto a new phylum but a descendant from the prokaryotic bacteria phylum.
Phylums are just names for early branches in the diversity of life, other taxon levels are also just names for other branches at different times in the diversity of life. So don't get hung up on the names, rather look at the process of branching descent forming nested hierarchies from common ancestor populations: that is the process of evolution in action over many generations.
In other words you comments are based on a very poor understanding of evolution, and you need to "reboot" and start over.
You then stray with this straw man:
The issue I take with your comments is that the body plans are not completely different
Not my claim! Body plans are sufficiently different to lay the blueprint of the phyla of animals we see around us today.
It was your implication, whether due to terminology or misunderstanding is irrelevant.
It's not a straw man that each "phylum" can be traces back to a common ancestor that is the original species descended from a parent population that was also the common ancestor for other phylum and that the differences at that time were not significantly different. What we see today is the product of millions of generations of evolution since those first species.
At a slightly different level we can compare the differences between mammals and reptiles and we can see that while there are specialized differences in traits there is also a lot of similarities based on their descent from a common ancestor population that was a tetrapod. There are more similarities than differences, even though a lot of time and a lot of generations have passed since they went separate ways from their common ancestor population. If we went back to when mammals and reptiles divided we would not see as much difference in species as we see now. At that time their "body plan" differences would be similar to the differences between horses and zebras, and the same holds for other devisions at the times they occurred.
You then say:
rather they have different specializations of a generally similar body plan.
Hmm Not sure what you are driving at. Organisms under Chordata obviously have body plans with general specializations that allow them to be classed under one phylum. However Chordata body plan very different for example from Echinodermata body plan and so on.
At one point they had a common ancestor population and no significant difference in "body plan" (minor variations would occur) -- then the population divided into daughter populations and they still have very similar "body plans" ... and the kept evolving along divergent paths, developing different "specializations" as they went, but still derived from the parent common ancestor "body plan" ... again the term "body plan" gets in the way and is confusing and misleading, while talking about having different inherited traits is better in describing what has occurred.
You say:
there is no major difference that I can see in body plans beyond the development of specialized adaptations.
Perhaps you shouldn't be looking under one phylum if you want to see differences. Major body plan differences exist between different phylum, say Chordata which have bilateral body plan and Echinodermata which have radial body plan, in addition to symmetry there are many other differences that add up to allow for sufficient grouping of organism into different phyla.
Which just shows the confusion resulting from using "body plan" instead of inherited traits. You are looking now at the result of divergent evolution from a common ancestor with a common body plan. What is different is that the divergent paths have resulted in different specializations of inherited traits along the way.
Remember that "phylum" (and any other taxon level) is just the arbitrary name of an arbitrary grouping that we use to identify which group is descendant from which daughter population.
If you look at cladistics this becomes a little clearer:
Cladistics - Wikipedia
quote:
Cladistics (from Greek κλάδος, klados, i.e. "branch")[1] is an approach to biological classification in which organisms are grouped together based on whether or not they have one or more shared unique characteristics that come from the group's last common ancestor and are not present in more distant ancestors. Therefore, members of the same group are thought to share a common history and are considered to be more closely related.[2][3][4][5]
The cladistic method interprets each character state transformation implied by the distribution of shared character states among taxa (or other terminals) as a potential piece of evidence for grouping. The outcome of a cladistic analysis is a cladogram — a tree-shaped diagram (dendrogram)[17] that is interpreted to represent the best hypothesis of phylogenetic relationships. ...
The cladogram to the right represents the current universally accepted hypothesis that all primates, including strepsirrhines like the lemurs and lorises, had a common ancestor all of whose descendants were primates, and so form a clade; the name Primates is therefore recognized for this clade. Within the primates, all anthropoids (monkeys, apes and humans) are hypothesized to have had a common ancestor all of whose descendants were anthropoids, so they form the clade called Anthropoidea. The "prosimians", on the other hand, form a paraphyletic taxon. The name Prosimii is not used in phylogenetic nomenclature, which names only clades; the "prosimians" are instead divided between the clades Strepsirhini and Haplorhini, where the latter contains Tarsiiformes and Anthropoidea.
If we did the same diagramming further back in time it would show other branches from the common ancestor populations, and end up with this kind of diagram:
quote:
Diagrammatic representation of the divergence of modern taxonomic groups from their common ancestor.
Note the absence of dependence on taxonomic level labels (phylums etc) and instead notice that each clade ("animals" would include us and many more species, and a couple of phyla ... but not all of them) are all evolved from common ancestors: that there are branching points where the common ancestor populations divided into the daughter populations at each branching point; and their descendants diverged more and more generation by generation.
Where would a "new phylum" fit in this representative scheme?
Where would a "new body plan" fit in this representative scheme?
Looking at the history of evolution on earth as depicted in this diagram shows how the terminology of "phylum" and "body plan" are artifacts of classification rather than products of evolution.
You show more confusion
Do birds and bats have different body plans or the same body plans with different specializations?
Erm (scratching my head) they both Chordata, obviously they have similar body plan. Do bats and snails have same body plan? Nope quite different!
Different now, but how different were their ancestors when they had just diverged from their common ancestor population? Less different than bats and birds. Compare embryos and you will see little difference in the early stages, before the specialized adaptations begin to develop.
The specialization you see has occurred since they diverged, over millenia and many many generations, not at the moment of divergence.
You said:
But yes, and the evidence is in the parts of the body plans that are shared and how one branch develops generation by generation from that common basis to reach the specialized variation on the general body plans of their ancestors.
And
Curiously, what we have observe is the fossil record,
What evidence? Until you can show evidence that unguided changes are capable of generating new, viable body plans all you have is another just so story. ...
Every new generation of every species shows the evolutionary process capable of generating new, viable body plans.
Every new speciation event shows the evolutionary process capable of generating new, viable body plans.
The fossil record merely documents how this has occurred in the past and how the species at different times were simply steps along the path to the diversity of today, how evolution from common ancestors has demonstrated the evolutionary process capable of generating new, viable body plans at every stage along the way.
... Something else could account for the homologies.If you compare a 1953 and a 1954 Corvette, shoulder to shoulder, then a 1954 and a 1955 model, and so on, the descent with modification is overwhelmingly obvious.
Taken as an example, the parts that are homologous are those that are the same from model to model, and the parts that are different are derived, they stand in for mutations in your analogy.
If you compared a corvette with a thunderbird, for another example, you would find many differences but still similar performance, the engines would be analogous.
You could very likely form a tree of the development of vehicles based on homologies and derived features, but there would be some aspects that make it more problematic than we find in life: when you compare other aspects of autos you see things that are not observed in life: rear window wipers for instance, did not develop and stayed in one line of vehicles, but quickly spread to many different makes and models. This horizontal transfer of new traits is not something you see in the diversification of multicellular life.
The aspects of vehicles that change from model to model are not inherited traits, as vehicles do not breed and when something doesn't work it can be replaced. Life doesn't do this either.
When we observe real life changes we see homologies and derived features in the process. When we look at the fossil record and use the observed homologies and derived features to sort the diversity of life into a cladistic chart we can check that pattern with the genetic evidence and see that it generally confirms the chart, and in some cases corrects it:
quote:
Every cladogram is based on a particular dataset analyzed with a particular method. Datasets are tables consisting of molecular, morphological, ethological[18] and/or other characters and a list of operational taxonomic units (OTUs) which may be genes, individuals, populations, species, or larger taxa that are presumed to be monophyletic and therefore to form, all together, one large clade; phylogenetic analysis infers the branching pattern within that clade. Different datasets and different methods, not to mention violations of the mentioned assumptions, often result in different cladograms. Only scientific investigation can show which is more likely to be correct.
Until recently, for example, cladograms like the following have generally been accepted as accurate representations of the ancestral relations among turtles, lizards, crocodilians, and birds:[19]
             Testiduines
---------------- turtles
|
| Lepidosauria
| ------------------ lizards
| |
-----------▼ | Crocodylomorpha
| Diapsida | ------------------ crocodilians
-------------♦ |
| Archosauria |
------------------•
| Dinosauria
------------------ birds
If this phylogenetic hypothesis is correct, then the last common ancestor of turtles and birds, at the ⊣ connection near the ▼ (a ⊤ in some browsers) lived earlier than the last common ancestor of lizards and birds, near the ♦. Most molecular evidence, however, produces cladograms more like this:[20]
             Lepidosauria
---------------- lizards
|
| Testiduines
| ------------------ turtles
Diapsida | |
-----------♦ | Crocodylomorpha
| | ------------------ crocodilians
-------------▼ |
| Archosauria |
------------------•
| Dinosauria
------------------ birds
If this is accurate, then the last common ancestor of turtles and birds lived later than the last common ancestor of lizards and birds. Since the cladograms provide competing accounts of real events, at most one of them is correct.
(Note I have modified the diagrams slightly from wikipedia so that the ▼, ♦, and • symbols would represent the common ancestors to the branches.)
The organisms\species just above and below from these common ancestor populations would be very similar in inherited traits or "body plans" to the point where anyone living then would have difficulty distinguishing them. The specializations that developed since then have led to the noticeable differences in body plans in the modern species.
... Something else could account for the homologies. ...
... and until you specify and demonstrate what that "something else" is you will have an empty argument based on wishful thinking rather than science.
Homology can tell you nothing about how a system could have evolved by numerous, successive, slight modifications. ...
Homology alone doesn't do this, but homology plus derived new traits does. Each of the "numerous, successive, slight modifications" would show up as derived features in the evolutionary history of each species.
... In other words, homology doesn’t necessarily imply evolution. ...
Homology implies relatedness, even your corvette analogy shows this, that species with a shared homology had a common ancestor that had that specific trait, and the more homologies there are implies that the common ancestor was more recent.
... Evidence for common ancestry is not evidence for the mechanism of Neo-Darwinism. ...
Common ancestry is evidence that speciation occurred, and until you develop, test and demonstrate an alternative process evolution remains the best explanation for the observed patterns of common ancestors in a nested hierarchy.
... Common ancestry can stand independent of Neo-Darwinsim and is readily accepted by those who reject Neo-Darwinism such as Michael Behe.
Curiously it doesn't matter what people say, as both the process of evolution and the process of speciation have been observed, thus confirming that the derivation of daughter populations from a common ancestral population does occur, and that this process forms nested hierarchies. This is sufficient to validate the concept that these two processes can be applied to natural history of life to arrange them into the overall nested hierarchy that is the tree of life:
Remember that:
The Theory of Evolution (ToE), stated in simple terms, is that the process of evolution over generations, and the process of divergent speciation, are sufficient to explain the diversity of life as we know it, from the fossil record, from the genetic record, from the historic record, and from everyday record of the life we observe in the world all around us.
The fossil record is a test of the ToE, and until you can find something in the fossil record that cannot be explained by these processes evolution remains the best explanation available.
Hope that was not too long, but it was either that or skip some of the misinformed statements in your post, or multiple replies that add up to the same total length.
Edited by RAZD, : like this

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 94 by Cedre, posted 04-12-2014 10:06 AM Cedre has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 221 of 969 (724315)
04-15-2014 10:12 PM
Reply to: Message 218 by Faith
04-15-2014 9:45 PM


difficult falsification is not absence of falsification
... The typical standard for falsifiability of the ToE given here is the idea of finding a mammal in the lower levels of the strata, where YECs also say they wouldn't have occurred ...
Let me simplify it further: something out of sequence as it is currently understood would need to be explained, either by changing what we currently understand or by proposing a new mechanism. That would be how science works.
Any breakdown of the nested hierarchy of life would present this problem.
Falsifiability is one of the hallmarks of genuine science. ...
Indeed, and the fossil record is a test of the ToE. As long as the fossil record can be explained by the processes of evolution and divergent speciation the theory is not invalidated. There remains the possibility of a new fossil -- any new fossil -- showing something that cannot be explained by the Theory of Evolution: that is a falsification test.
Genetics is another test of the ToE, and as long as there is no conflict between the fossil record and the genetic record the theory is not invalidated. There remains the possibility of a new genetic information -- any new genetic information -- showing something that cannot be explained by the Theory of Evolution: that is a falsification test.
The fact that these seem unlikely to occur is not because these are not real falsification tests, but because these tests have already been run many many many times with no hint of falsification occurring, and this is evidence of the Theory of Evolution being a very strong theory, so strong that the likelihood of any significant modification necessary is very remote.
This happens when theories are very very good at explaining all the evidence. Like gravity.
... where YECs also say they wouldn't have occurred. I'm sorry you seem to be unable to follow the argument but that's your problem, not mine.
Which of course is absolutely and totally irrelevant to whether or not evolution is falsifiable.
Edited by RAZD, : ...

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 218 by Faith, posted 04-15-2014 9:45 PM Faith has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 241 of 969 (724350)
04-16-2014 11:21 AM
Reply to: Message 198 by NoNukes
04-15-2014 12:28 PM


a proper falsification test vs an undoable test
I think a valid objection to the cow test is that it is not something that MUST occur if the ToE is false.
You are making the logical error that I believe Faith actually avoided, although perhaps not clearly so.
What you are describing is not falsification of TOE. What you are describing is how we might find evidence or the lack thereof of some other theory.
Curiously I don't see how you get that from specifying something that MUST be true if ToE is false.
The trouble I have with the Precambrian Cow (or an Ordovician Aardvark) is that it is not a test you can specifically go out and do, it is something that could (if the ToE were false) just turn up on its own.
Another would be trait transfer from one branch to another -- Otters with Octopus eyes for example.
This is arm-chair ad hoc thinking ...
I think Faith is saying that the cow test is an insincere offering by pro-evolutioners. ...
And I agree. It is more like a flippant off-the-cuff statement than a ruggedly developed and scientifically structured test, and if this is the only test of the theory it seems rather naive to me to claim it is a true test that will result in the invalidation of the theory.
One instance of a fossil out of sequence would not question the whole vast array of fossils that are in sequence: it would be an unexplained anomaly leaving the ToE as 99.9% accurate to date, rather than 100.0% accurate to date. I hardly call that falsification. Science would shrug and carry on. Anomalies exist for other theories used in science.
A true scientific skeptic, imho, will look for a test that can be actively pursued and run to test their theory. A normal process is to develop an anti-theory and use it to make predictions, and then test those predictions.
For an interesting discussion (yes I know but) see http://www.conservapedia.com/...:Falsifiability_of_Evolution
quote:
Many people assume the "Theory of Evolution" is a single theory. It is not. Rather, it is a collection of 1,000,000+ theories, papers, experiments, observations and tests, all of which contribute to the overall theory of evolution". ...
A common false assumption made is that disproving one of the underlying theories, invalidates the entire theory of evolution. ... . An error in a single theory does not disprove the larger body of knowledge. Falsifying the "Theory of Evolution" would require disproving thousands of supporting theories.PerpetualAngst 16:23, 20 June 2007 (EDT)
Now I don't agree with PerpetualAngst that there are millions of theories rolled into the ToE, it seems to me that this is conflating the ToE with the science of evolution (see comments in the link re falsifying physics), and that there are a number of processes involved that affect the evolution of organisms.
PerpetualAngst also references ://29+ Evidences for Macroevolution: Part 1 "for a much more detailed argument in favor of common descent" and it has this:
quote:
Potential Falsification:
Thousands of new species are discovered yearly, and new DNA and protein sequences are determined daily from previously unexamined species (Wilson 1992, Ch. 8). At the current rate, which is increasing exponentially, nearly 30,000 new sequences are deposited at GenBank every day, amounting to over 38 million new bases sequenced every day. Each and every one is a test of the theory of common descent. When I first wrote these words in 1999, the rate was less than one tenth what it is today (in 2006), and we now have 20 times the amount of DNA sequenced.
Based solely on the theory of common descent and the genetics of known organisms, we strongly predict that we will never find any modern species from known phyla on this Earth with a foreign, non-nucleic acid genetic material. We also make the strong prediction that all newly discovered species that belong to the known phyla will use the "standard genetic code" or a close derivative thereof. For example, according to the theory, none of the thousands of new and previously unknown insects that are constantly being discovered in the Brazilian rainforest will have non-nucleic acid genomes. Nor will these yet undiscovered species of insects have genetic codes which are not close derivatives of the standard genetic code. In the absence of the theory of common descent, it is quite possible that every species could have a very different genetic code, specific to it only, since there are 1.4 x 10^70 informationally equivalent genetic codes, all of which use the same codons and amino acids as the standard genetic code (Yockey 1992). This possibility could be extremely useful for organisms, as it would preclude interspecific viral infections. However, this has not been observed, and the theory of common descent effectively prohibits such an observation.
As another example, nine new lemur and two marmoset species (all primates) were discovered in the forests of Madagascar and Brazil in 2000 (Groves 2000; Rasoloarison et al. 2000; Thalmann and Geissmann 2000). Ten new monkey species have been discovered in Brazil alone since 1990 (Van Roosmalen et al. 2000). Nothing in biology prevents these various species from having a hitherto unknown genetic material or a previously unused genetic codenothing, that is, except for the theory of common descent. However, we now know definitively that the new lemurs use DNA with the standard genetic code (Yoder et al. 2000); the marmosets have yet to be tested.
Furthermore, each species could use a different polymer for catalysis. The polymers that are used could still be chemically identical yet have different chiralities in different species. There are thousands of thermodynamically equivalent glycolysis pathways (even using the same ten reaction steps but in different orders), so it is possible that every species could have its own specific glycolysis pathway, tailored to its own unique needs. The same reasoning applies to other core metabolic pathways, such as the citric acid cycle and oxidative phosphorylation.
Finally, many molecules besides ATP could serve equally well as the common currency for energy in various species (CTP, TTP, UTP, ITP, or any ATP-like molecule with one of the 293 known amino acids or one of the dozens of other bases replacing the adenosine moiety immediately come to mind). Discovering any new animals or plants that contained any of the anomalous examples proffered above would be potential falsifications of common ancestry, but they have not been found.
Note predictions of what we should see if the theory is true and what we should not see - things that would occur if the theory were false.
The article also goes on to discuss nested hierarchies and the difference between cladograms of cars and cladograms of organisms (an issue Cedre brought up).
These are much more doable, stronger, falsification tests imho.
Edited by RAZD, : ...
Edited by RAZD, : superscript 70

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 198 by NoNukes, posted 04-15-2014 12:28 PM NoNukes has replied

Replies to this message:
 Message 242 by Percy, posted 04-16-2014 11:43 AM RAZD has replied
 Message 244 by NoNukes, posted 04-16-2014 1:31 PM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 245 of 969 (724365)
04-16-2014 1:48 PM
Reply to: Message 242 by Percy
04-16-2014 11:43 AM


Re: a proper falsification test vs an undoable test
Dr A addressed this several times. If a theory is true, there is no potential falsification that you could go out there and actually do.
And I expect that Faith and a number of others will say that this just shows that evolution is unfalsifiable.
Creationists could look all around the world for the most likely place to turn up a fossil that doesn't fit the theory of evolution. They don't bother because they know in their hearts they'll never find one.
Or they just think it is not a reasonable test. One anomaly does not invalidate a theory ...
Falsifiability - Wikipedia
quote:
Although the logic of nave falsification is valid, it is rather limited. Nearly any statement can be made to fit the data, so long as one makes the requisite 'compensatory adjustments'. Popper drew attention to these limitations in The Logic of Scientific Discovery in response to criticism from Pierre Duhem. W. V. Quine expounded this argument in detail, calling it confirmation holism. To logically falsify a universal, one must find a true falsifying singular statement. But Popper pointed out that it is always possible to change the universal statement or the existential statement so that falsification does not occur. On hearing that a black swan has been observed in Australia, one might introduce the ad hoc hypothesis, 'all swans are white except those found in Australia'; or one might adopt another, more cynical view about some observers, 'Australian bird watchers are incompetent'.
There was an anomaly in Newton's Law (Theory) of Gravity with the orbit of Mercury, this was resolved with Relativity (while his law remained accurate enough to land objects on Mars), and then there is the anomaly in Relativity that turns up with the rotation rate of galaxies ... and we have the ad hoc addition of dark stuffs ...
Anomalies alone are not sufficient to invalidate theories.
Curiously, imho, the attitude that this Precambrian Cow type of test is a "good" falsification test of evolution smacks of self-satisfaction, confirmation bias and hubris, rather than a hard skeptical scientific developed rugged test.
The test for differences in the DNA molecules and amino acids is to my mind much much more directly linked to falsificationability for the ToE: life has been very picky about what molecules are used and there are many more to choose from: any of the amino acids etc listed (see Message 241 near end) cropping up would be stronger evidence against the ToE AND are realistic to look for:
quote:
... In the absence of the theory of common descent, it is quite possible that every species could have a very different genetic code, specific to it only, since there are 1.4 x 10^70 informationally equivalent genetic codes, all of which use the same codons and amino acids as the standard genetic code (Yockey 1992). ...
Finally, many molecules besides ATP could serve equally well as the common currency for energy in various species (CTP, TTP, UTP, ITP, or any ATP-like molecule with one of the 293 known amino acids or one of the dozens of other bases replacing the adenosine moiety immediately come to mind). ...
When we look at the experiments on self-replicating molecules we see that a number of rather different systems can result in successful self-replication, and logically any one of those could have formed a basis for the origin of life: without common descent and nested hierarchies there is no reason that any one of these other molecules could be involved.
Fossils aren't always preserved, but chemical irregularities should be much easier to search for, so I find those tests to be much more realistic, more multilevel, and much more doable, than finding the mad cow that buries itself in the precambrian pasture.
If evolution is not true what MUST we see? Something different in the DNA and amino acids used in different organisms -- different bases, different energy transport, something other than the highly selective system we see (one in 1.4 x 10^70 leaves a lot of room for a second or third code system).

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 242 by Percy, posted 04-16-2014 11:43 AM Percy has replied

Replies to this message:
 Message 247 by New Cat's Eye, posted 04-16-2014 3:07 PM RAZD has seen this message but not replied
 Message 296 by Percy, posted 04-17-2014 9:04 AM RAZD has seen this message but not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 408 of 969 (724686)
04-19-2014 3:36 PM
Reply to: Message 403 by Percy
04-19-2014 10:49 AM


Re: granite schist and basalt
pit nick
... the Cardenas Basalts intrusion that I've drawn a red square around also formed a layer, this one parallel to the Unkar Group. ...
Don't you mean perpendicular?

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 403 by Percy, posted 04-19-2014 10:49 AM Percy has seen this message but not replied

Replies to this message:
 Message 413 by edge, posted 04-19-2014 4:34 PM RAZD has seen this message but not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 410 of 969 (724689)
04-19-2014 4:16 PM
Reply to: Message 196 by Dr Adequate
04-15-2014 11:56 AM


prediction: nested hierarchies; anti-prediction: not nested hierarchies
Let's see if we can get back on topic ?
Yes, but again you can't say that that MUST happen if it was false, you can only say that it can't happen if it's true.
If descent with modification were not true then nested hierarchies would not form, and instead there must be some other pattern formed.
When we look at vehicles we see that no single nested hierarchy can be formed that explains all the homologies, and that any attempt to do so results in significantly different patterns when different aspects are used for homologies.
Using color you get one pattern
Number of passengers gives another pattern
Number of openings gives another pattern
Engine cylinder number gives another pattern
Carburetor construction gives another pattern
Rear window wipers gives another pattern
Tire type gives another pattern
etc
When you try to combine them you get cross-links rather than linear branches.
This is what you should see if descent with modification were wrong, and this demonstrates that the changes seen in vehicles are not due to biological evolution but to another process.
Edited by RAZD, : ...

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 196 by Dr Adequate, posted 04-15-2014 11:56 AM Dr Adequate has not replied

Replies to this message:
 Message 411 by Faith, posted 04-19-2014 4:26 PM RAZD has replied
 Message 427 by NoNukes, posted 04-20-2014 12:43 AM RAZD has seen this message but not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 414 of 969 (724693)
04-19-2014 4:43 PM
Reply to: Message 244 by NoNukes
04-16-2014 1:31 PM


Back to the topic: a proper falsification test vs an undoable test
You could go on a fossil hunt, but let's say that you are unable to do that? So what? The question of falsification is not about what you personally can do, it is about what is possible and what has or has not been found.
The probability of a single organism becoming fossilized is low ... very low, agreed?
The probability of a single fossil being found is also low ... very low, agreed?
So this test has a very low probability of being actualized even if a precambrian cow existed.
Except that it is not the only test. The answer is deliberately flip ...
Then why not provide a real test that is not flip and dismissive (which is one of my objections to it. It is condescending and obstructive rather than educative and elucidating.
... Anyone, even a disbeliever, who if familiar with the science ought to be able to come up with their own falsification. ...
Curiously I am not so impressed with the ability of Americans raised on watered down science to even think that they could develop their own test, and I also think that it should be considered a valid question, one that should be answerable for every theory.
... But someone ranting about the TOE being just mind games is not that person. I would not spend 2 minutes trying to explain a scientific topic to Faith. You do seem to have that kind of patience, but I doubt you can get any better results.
And I am not concerned with Faith so much as I am with other readers who may be put off by flip responses to serious questions.
What I would prefer to see would be comments more on the lines of:
The theory of evolution predicts nested hierarchies based on descent with modification, and thus if the theory is false then the nested hierarchies must be violated. An example of such a violation would be an otter with octopus eyes, a mammal with eyes from a cephalopod. Another would be an organism that uses another molecule than ATP for energy transfer.
This would mean that a new\additional process would be needed to explain the anomalies, such as a mechanism for horizontal transfer of whole sections of DNA.
AND the result would likely be more a refinement of the ToE to include this new mechanism (in the way that relativity refined Newton's law of gravity).

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 244 by NoNukes, posted 04-16-2014 1:31 PM NoNukes has replied

Replies to this message:
 Message 416 by NoNukes, posted 04-19-2014 4:51 PM RAZD has seen this message but not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 417 of 969 (724696)
04-19-2014 5:17 PM
Reply to: Message 411 by Faith
04-19-2014 4:26 PM


Re: prediction: nested hierarchies; anti-prediction: not nested hierarchies
Nested hierarchies is some kind of article of faith you think proves evolution but although I've looked at discussions of this phenomenon I must be missing something. Could you please explain graphically and in detail what a nested hierarchy is? Thank you.
When speciation occurs you have two (or more) daughter populations that have evolved from a common ancestral (pre-speciation) parent population, daughter populations that no longer share genetic material and the different mutations the populations accrue.
When one of these daughter populations has another speciation event, dividing into (grand)daughter populations they too will not share genetic material or the different mutations those populations accrue. Same with any further speciation events, and when we plot these lineages we will see something like this:
Where A, B, C and G represent speciation events and the common ancestor populations of a clade that includes the common ancestor species and all their descendants: C and below form a clade that is part of the B clade, B and below form a clade that is also part of the A clade; G and below also form a clade that is also part of the A clade, but the G clade is not part of the B clade.
The C clade (C, D, and E) are nested within the B clade (B, C, D, E and F).
The B clade (B, C, D, E and F) and the G clade (G, H and I) are both nested inside the A clade (A, B, C, D, E, F, G, H and I)
Deriving cladograms from the available evidence is not without problems ...
Cladistics - Wikipedia
quote:
Every cladogram is based on a particular dataset analyzed with a particular method. Datasets are tables consisting of molecular, morphological, ethological[18] and/or other characters and a list of operational taxonomic units (OTUs) which may be genes, individuals, populations, species, or larger taxa that are presumed to be monophyletic and therefore to form, all together, one large clade; phylogenetic analysis infers the branching pattern within that clade. ...
Until recently, for example, cladograms like the following have generally been accepted as accurate representations of the ancestral relations among turtles, lizards, crocodilians, and birds:[19]
Testiduines
           ---------------- turtles
           |
           |              Lepidosauria
           |            ------------------ lizards
           |            |
----------▼|            |                   Crocodylomorpha
           | Diapsida   |                 ------------------ crocodilians
           ------------♦|                 |
                        | Archosauria     |
                        -----------------•|
                                          | Dinosauria
                                          ------------------ birds
If this phylogenetic hypothesis is correct, then the last common ancestor of turtles and birds, at the ⊣ connection near the ▼ (a ⊤ in some browsers) lived earlier than the last common ancestor of lizards and birds, near the ♦. Most molecular evidence, however, produces cladograms more like this:[20]
Lepidosauria
           ---------------- lizards
           |
           |              Testiduines
           |            ------------------ turtles
 Diapsida  |            |
----------♦|            |                   Crocodylomorpha
           |            |                 ------------------ crocodilians
           ------------▼|                 |
                        | Archosauria     |
                        -----------------•|
                                          | Dinosauria
                                          ------------------ birds
If this is accurate, then the last common ancestor of turtles and birds lived later than the last common ancestor of lizards and birds. Since the cladograms provide competing accounts of real events, at most one of them is correct.
Here we see that there is a slight disagreement between the fossil based cladogram and the genetic based cladogram ... mostly over which branched off first, turtles or lizards.
This disagreement doesn't violate the nested hierarchies formed, but flying turtles with bird type feathered wings would, because birds and bird type feathered wings evolved after turtles split from the lineage of descent.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 411 by Faith, posted 04-19-2014 4:26 PM Faith has replied

Replies to this message:
 Message 429 by Faith, posted 04-20-2014 2:27 AM RAZD has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 441 of 969 (724739)
04-20-2014 8:52 AM
Reply to: Message 429 by Faith
04-20-2014 2:27 AM


Re: prediction: nested hierarchies; anti-prediction: not nested hierarchies
... In any case I get it, it's basically the principles of microevolution which are never in dispute, ...
Correct.
(1) The process of evolution involves changes in the composition of hereditary traits, and changes to the frequency of their distributions within breeding populations from generation to generation, in response to ecological challenges and opportunities.
This is sometimes called microevolution, however this is the process through which all species evolve and all evolution occurs at the breeding population level.
(2) The process of divergent speciation involves the division of a parent population into two or more reproductively isolated daughter populations, which then are free to (micro) evolve independently of each other.
The reduction or loss of interbreeding (gene flow, sharing of mutations) between the sub-populations results in different evolutionary responses within the separated sub-populations, each then responds independently to their different ecological challenges and opportunities, and this leads to divergence of hereditary traits between the subpopulations and the frequency of their distributions within the sub-populations.
The process of forming a nested hierarchy by descent of new species from common ancestor populations, via the combination of phyletic change in species (evolution over many generations) and divergent speciation, and resulting in an increase in the diversity of life, is sometimes called macroevolution. This is often confusing, because there is no additional mechanism of evolution involved, rather this is just the result of looking at evolution over many generations and different ecologies.
...to which has been added observations of completely different kinds/species based on some collection of similarities that seem to make them fit right in. Their own microevolution into breeds and races then continues the format, and then again you have to piece them together with some other kind that is subjectively determined to have enough similar characteristics to be ancestor or descendant. ...
Such as the objective observation that lizards, turtles, crocodiles and birds are all tetrapods that have the same bone patterns (morphology) in their skeletons ...
That they all have limbs with one bone near the torso, with similar shoulder and hip structures, then two bones below the elbow\knee joint (which is also a similar feature) and then many bones below the wrist\ankle joint (which again is a similar feature) ...
That they all have similar vertebrae running from head to tail, and ribs and skull bones ...
Etc Etc Etc ... and by comparing these bones, their various adaptations (like the shell of the turtle and the wind of the bird), and when they branched from a common ancestor based on morphology gave us this cladogram:
Testiduines
           ---------------- turtles
           |
           |              Lepidosauria
           |            ------------------ lizards
           |            |
----------▼|            |                   Crocodylomorpha
           | Diapsida   |                 ------------------ crocodilians
           ------------♦|                 |
                        | Archosauria     |
                        -----------------•|
                                          | Dinosauria
                                          ------------------ birds
While using genetic markers in genomes of these various organisms gave us this cladogram:
Lepidosauria
           ---------------- lizards
           |
           |              Testiduines
           |            ------------------ turtles
 Diapsida  |            |
----------♦|            |                   Crocodylomorpha
           |            |                 ------------------ crocodilians
           ------------▼|                 |
                        | Archosauria     |
                        -----------------•|
                                          | Dinosauria
                                          ------------------ birds
Where the only "dispute" is which came first, the turtle or the lizard ...
A similar cladogram could be developed from embryology and determining the points at which fetal development diverged. A lot of the morphological and embryological observations were made before Darwin and his theory explained the causal basis for the observed structure of relatedness
... and then again you have to piece them together with some other kind that is subjectively determined to have enough similar characteristics to be ancestor or descendant. ...
It is an objective process Faith, one that has been replicated with the same results. Once again we see that genetics could have provided an entirely different picture ... but didn't.
The consilience of similar results from entirely different processes reinforces the validity of the whole.
... So of course I would have to question the artificial connections between kinds but to do so would mean having a much more detailed description of just what characteristics are being invoked to create the supposed continuation from microevolution to macro at each level. ...
All characteristics are used. The more homologies and derived traits the better. Characteristics such as the heart structure:
Adelaidean -- Crocodile evolution no heart-warmer
quote:
"There's an assumption that warm-bloodedness always evolves from cold-bloodedness, because being warm-blooded is seen as better - this is a reversal of that thinking," he said.
"The strongest clue comes from the four chambered heart that living crocodiles share with birds and mammals. Such a heart perfectly separates blood going to the lungs from that going to the body, which is a requirement for the high blood flow rates and high metabolic rates characteristic of warm-bloodedness. However, living crocodiles are cold-blooded, so it didn't make sense for them to have a warm-blooded heart.
Professor Seymour's work on the development of salt-water crocodile hearts and that by Christina Bennett-Stamper on American alligators shows that the embryos go through stages that indicate their evolutionary history.
"When I looked at the palaeontology of crocodiles, a consistent picture appeared-the earliest ancestors of crocodiles were definitely not sit-and-wait predators. Instead, many had long legs and some ran around on only two legs. These were obviously highly active, terrestrial predators which would have been well served by warm-bloodedness and a four chambered heart.
"Between 200 and 65 million years ago, the crocodilian lineage diversified into more than 150 genera in all kinds of habitats from land-based to fresh water and the ocean," he said.
... Probably too much for me to take on at this point. But I do thank you for going to that trouble to spell it out.
Well it is your choice whether you want to learn or hide from knowledge.
Edited by RAZD, : add

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 429 by Faith, posted 04-20-2014 2:27 AM Faith has not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 480 of 969 (724848)
04-21-2014 4:47 PM
Reply to: Message 478 by New Cat's Eye
04-21-2014 1:06 PM


Re: Oh look
yep, can't even get a bump trying to get back on topic.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 478 by New Cat's Eye, posted 04-21-2014 1:06 PM New Cat's Eye has not replied

Replies to this message:
 Message 481 by Coyote, posted 04-21-2014 6:16 PM RAZD has seen this message but not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(4)
Message 495 of 969 (724926)
04-22-2014 4:35 PM
Reply to: Message 489 by Faith
04-21-2014 10:45 PM


There are scientific arguments against young earth creationism
I grant that both of these phenomena appear to support an Old Earth, at least an older Earth than the Biblical Young Earth. There are phenomena on both sides of the question it seems to me.
Now consider that there are many things younger than the earth that can be found ... and all they show is that the earth is at least as old as these things but could be older.
Curiously I have trouble conceiving of how one could find things (other than meteors perhaps) that could be older than the earth, certainly not living things, evolved things, fossils of once living things.
We were discussing nested hierarchies and how they form clades.
To my mind clades are the most translatable concept from evolutionary biology to creationist "kinds" -- as they are groups descended from common ancestor populations.
So the question becomes on where you stop forming "kind" clades and why. This is basically the point we were at on Message 441:
...to which has been added observations of completely different kinds/species based on some collection of similarities that seem to make them fit right in. Their own microevolution into breeds and races then continues the format, and then again you have to piece them together with some other kind that is subjectively determined to have enough similar characteristics to be ancestor or descendant. ...
Such as the objective observation that lizards, turtles, crocodiles and birds are all tetrapods that have the same bone patterns (morphology) in their skeletons ...
That they all have limbs with one bone near the torso, with similar shoulder and hip structures, then two bones below the elbow\knee joint (which is also a similar feature) and then many bones below the wrist\ankle joint (which again is a similar feature) ...
That they all have similar vertebrae running from head to tail, and ribs and skull bones ...
Or we can talk about mammals.
... and then again you have to piece them together with some other kind that is subjectively determined to have enough similar characteristics to be ancestor or descendant. ...
Such as teeth: why do all (placental) mammals have the same basic pattern of teeth, why do cats have canines (like dogs) and not different specialized teeth for cats?
Especially when marsupial (mammals) have a different basic pattern of teeth?
Not knowing where to draw the line to divide living organisms into clades is - imho - one of the major problems with creationism: if it were true then there should be clear and distinct ends of separate clades that would show what the created kinds are.
Edited by RAZD, : spling

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 489 by Faith, posted 04-21-2014 10:45 PM Faith has not replied

Replies to this message:
 Message 496 by edge, posted 04-22-2014 6:08 PM RAZD has seen this message but not replied
 Message 497 by NoNukes, posted 04-22-2014 7:56 PM RAZD has seen this message but not replied

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024