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Baffling genetic barrier in some closely related species prevents interbreding

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  • #16
    Originally posted by jordanriver View Post
    if that's all it takes, it seems to me rapid speciation is more common than was previously thought.
    And you Bible-God YECs will need all you can get to produce the current biodiversity from Noah d'Ark's cargo.

    K54

    Comment


    • #17
      Originally posted by Truthseeker View Post
      What might embracing the absurd lead to?
      If -- like me -- you find the universe and life in it meaningless and absurd, embracing that absurdity can be a nice way of coping with it.

      In other words, it's a good -- if temporary -- painkiller in lieu of finding God.
      Last edited by Duragizer; 09-26-2014, 05:18 AM.
      "When the Western world accepted Christianity, Caesar conquered; and the received text of Western theology was edited by his lawyers…. The brief Galilean vision of humility flickered throughout the ages, uncertainly…. But the deeper idolatry, of the fashioning of God in the image of the Egyptian, Persian, and Roman imperial rulers, was retained. The Church gave unto God the attributes which belonged exclusively to Caesar."

      — Alfred North Whitehead

      Comment


      • #18
        Originally posted by Duragizer View Post
        If -- like me -- you find the universe and life in it meaningless and absurd, embracing that absurdity can be a nice way of coping with it.

        In other words, it's a good -- if temporary -- painkiller in lieu of finding God.
        I can kinda see what you're saying, but, man -- from your avatar you are one butt ugly chick.



        K54

        Comment


        • #19
          Originally posted by jordanriver View Post
          if that's all it takes, it seems to me rapid speciation is more common than was previously thought.
          Yes and no, it does demonstrate that there are different mechanisms and circumstances for speciation to occur, and actual physical isolation is not necessary. This reflects only one circumstance in a much broader picture, where subspecies, not species, genetically disassociate from interbreeding. Over time the subspecies will likely evolve, specialize and adapt to different environments and food sources, i. e. Darwin's Finches of the Galapagos Islands. This type of adaptation and genetic drift, from subspecies to different species is becoming well known, and it takes a long time to occur,
          Glendower: I can call spirits from the vasty deep.
          Hotspur: Why, so can I, or so can any man;
          But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

          go with the flow the river knows . . .

          Frank

          I do not know, therefore everything is in pencil.

          Comment


          • #20
            JR reveals a fascinating point that I've never heard from a fideist YEC.

            She believes evolution is OK if it happens really fast.

            But slow evolution not so much.

            Is it any wonder that "debate" with YECs is ticklishy difficult?

            K54

            Comment


            • #21
              Originally posted by shunyadragon View Post
              Yes and no, it does demonstrate that there are different mechanisms and circumstances for speciation to occur, and actual physical isolation is not necessary. This reflects only one circumstance in a much broader picture, where subspecies, not species, genetically disassociate from interbreeding. Over time the subspecies will likely evolve, specialize and adapt to different environments and food sources, i. e. Darwin's Finches of the Galapagos Islands. This type of adaptation and genetic drift, from subspecies to different species is becoming well known, and it takes a long time to occur,
              I think tabibito may have had it right, in post 4, that maybe the birds don't like each other's songs.
              The SciAm article you cited notes imprinting. This is an epigenetic phenomenon.
              In Eva Jablonka's 'Evolution in Four Dimensions' she cites examples of mate rejection based on social behavior,
              an evidence example on p 185
              EVOLUTION IN FOUR DIMENSIONS Eva Jablonka and Marion Lamb ISBN 9780262600699
              p 185
              "There are no observations or experiments that unambiguously show purely cultural speciation. But the same is true for most of the suggested mechanisms of speciation in animals. However, although direct evidence is lacking, there are experiments that provide good circumstantial evidence for the importance of behavioral imprinting in speciation. The animals that have supplied it are African parasitic finches--birds that, like some cuckoos and cowbirds, lay their eggs in the nests of others, who are therefore tricked into rearing their offspring for them. Robert Payne and his colleagues, who have been studying parasitic birds for over thirty years, have shown experimentally how cultural transmission could promote rapid speciation. They took eggs of a parasitic species, and put them in the nests of a species unaccustomed to parasites. The new hosts incubated the eggs and looked after the parasite nestlings with the same loving care they showed to their genetic offspring. Not surprisingly, the young who grew up in the nest of the new host became imprinted on the song of their foster father. When adult, the males sang his song, and females were attracted to the males who were singing it, preferring the song of these males to that of those reared by the normal host.
              So within one generation, the parasites of the new host species had become at least partially reproductively isolated from the species from which they originated. Their reproductive isolation was the result of imprinting, which made females prefer males who sing their foster parents' song. Imprinting also made the females lay their eggs in the nests of their foster parents' species, so their offspring were exposed to the same type of imprinting stimuli as they themselves experienced., and they should continue to parasitize the new host. Eventually, if the experiment were to go on long enough, reproductive isolation might be stabilized through natural selection of morphological variations in the parasite that lead to even more devoted prenatal care by the hosts (although the parasitized host would almost certainly change too). But that is speculation.
              of course, I don't know what "long enough" refers to.
              To say that crony capitalism is not true/free market capitalism, is like saying a grand slam is not true baseball, or like saying scoring a touchdown is not true American football ...Stefan Mykhaylo D

              Comment


              • #22
                and here is a letters to Nature 'abstract' about the plausibility of sympatric speciation

                NATURE 424, 928-931 (21 August 2003)
                Speciation by host switch in brood parasitic indigobirds

                "A growing body of empirical and theoretical work supports the plausibility of sympatric speciation1, 2, 3, but there remain few examples in which all the essential components of the process are well understood. The African indigobirds Vidua spp. are host-specific brood parasites. Indigobird nestlings are reared along with host young, and mimic the mouth markings of their respective hosts4, 5, 6. As adults, male indigobirds mimic host song4, 5, 6, 7, whereas females use these songs to choose both their mates and the nests they parasitize8. These behavioural mechanisms promote the cohesion of indigobird populations associated with a given host species, and provide a mechanism for reproductive isolation after a new host is colonized. Here we show that all indigobird species are similar genetically, but are significantly differentiated in both mitochondrial haplotype and nuclear allele frequencies. These data support a model of recent sympatric speciation. In contrast to the cuckoo Cuculus canorus, in which only female lineages are faithful to specific hosts9, 10, host switches have led to speciation in indigobirds because both males and females imprint on their hosts8, 11.
                http://www.nature.com/nature/journal...ture01863.html
                with sympatric speciation, you don't have to go too far,
                ...plus, if you stay in the same neighborhood , possibility of rapid genetic change through horizontal gene transfer
                To say that crony capitalism is not true/free market capitalism, is like saying a grand slam is not true baseball, or like saying scoring a touchdown is not true American football ...Stefan Mykhaylo D

                Comment


                • #23
                  Hey JR,

                  Why would you care about plausibility of short term speciation (a few ten thousand years?) when you KNOW that YHWH Elohim miraculously effected all that supercalifragilistic speciation after YE Noah d'Ark's Greate Fludd?

                  K54

                  Comment


                  • #24
                    Originally posted by jordanriver View Post
                    and here is a letters to Nature 'abstract' about the plausibility of sympatric speciation
                    with sympatric speciation, you don't have to go too far,
                    ...plus, if you stay in the same neighborhood , possibility of rapid genetic change through horizontal gene transfer[/QUOTE]

                    Based on the problems of hundreds of millions of known species and extinction of species over billions of years, you would have to provide more details of what you propose rapid genetic change . Yes some mechanisms of speciation do have the possibility of rapid genetic change and speciation in terms of thousands of years, but most mechanisms are observed to be slow, involving at least tens of thousands of years. Some species observed in the fossil record and living today have not changed for millions of years.
                    Glendower: I can call spirits from the vasty deep.
                    Hotspur: Why, so can I, or so can any man;
                    But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

                    go with the flow the river knows . . .

                    Frank

                    I do not know, therefore everything is in pencil.

                    Comment


                    • #25
                      Originally posted by shunyadragon View Post
                      Based on the problems of hundreds of millions of known species and extinction of species over billions of years, you would have to provide more details of what you propose rapid genetic change . Yes some mechanisms of speciation do have the possibility of rapid genetic change and speciation in terms of thousands of years, but most mechanisms are observed to be slow, involving at least tens of thousands of years. Some species observed in the fossil record and living today have not changed for millions of years.[/
                      QUOTE]
                      what if they aren't technically "extinct"
                      according to Berkeley page on The Dinosauria
                      http://www.ucmp.berkeley.edu/diapsids/dinosaur.html

                      so if dinosaurs still exist, 'in birds', is it possible to "extract them" back out of birds:
                      THE TELEGRAPH Science Dec 22, 2013
                      http://www.telegraph.co.uk/science/d...dinosaurs.html
                      "...but dinosaurs could theoretically be brought back to life, according to an Oxford biochemist.
                      Dr. Alison Woollard said it would be theoretically possible to recreate ancient animals, through the DNA of birds.
                      By identifying and altering certain genes found in the DNA of modern birds, she believes scientists may be able to "design" genomes of the prehistoric creatures.
                      The theory echoes the plot of Jurassic Park, but comes after a recent attempt to bring back the animals using techniques more faithful to those used in the 1993 film failed....

                      ....however Dr. Woollard, from Oxford University's Department of Biochemistry, has suggested the feat could be achieved by "de-evolving" birds.
                      "We know that birds are the direct descendants of dinosaurs, as proven by an unbroken line of fossils which tracks the evolution of the lineage from creatures such as the velociraptor or T-Rex through to the birds flying around today," said Dr. Woollard.
                      "The most famous of these is Archaeopteryx, a fossil which clearly shows the transition between feathered dinosaurs and modern birds.
                      "This evolution implies that buried deep within the DNA of today's birds are switched-off genes that control dinosaur-like traits.
                      "Could we 'rewind' evolution by switching these genes back on and using them to guide the development of that bird's offspring, and its offspring's offspring, backwards?"
                      All animals and plants are related, sharing a common ancestor that lived about 1.6 billion years ago.
                      "In theory we could use knowledge of the genetic relationship of birds to dinosaurs to 'design' the genome of a dinosaur," said Dr. Woollard.
                      source

                      Michio Kaku, theoretical physicist, futurist, and a communicator and popularizer of science, host of several TV specials for the BBC, the Discovery Channel, the History Channel, and the Science Channel, on one of his many youtube videos says it's EPIGENETICS (start about 2:40 or 2:50)
                      http://www.youtube.com/watch?v=8c-EWSmOgDc

                      Epigenetics explained to non scientists like me, (but I have to watch it more than once (or twice or five times maybe), from the popular NOVA's Neil DeGrasse Tyson
                      http://www.youtube.com/watch?v=7WEHoCA1hpo

                      (transcript) http://www.pbs.org/wgbh/nova/transcr..._sciencen.html

                      (at 5:00 of the video)
                      Duke University's Randy Jirtle: "....the genome is being like a computer, the hardware of a computer, the epigenome would be like the software that tells the computer when to work, how to work, and how much

                      Neil DeGrasse Tyson: "in fact, it's the epigenome that tells our cells what sort of cells they should be
                      ....skin, hair, heart,
                      You see, all these cells have the same genes. But their epigenomes silence the unneeded ones to make cells different from one another. Epigenetic instructions pass on as cells divide, but they're not necessarily permanent. Researchers think they can change, especially during critical periods like puberty or pregnancy.
                      if the genes are already there, you don't need the slow process of gene-based mutation and natural selection.
                      Epigenetics can react to the environment and change within a few generations.

                      and if you "lose" a species, maybe you can get it back , changes IN REVERSE

                      http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1392256/

                      EPIGENTICS The Science of Change
                      The word "epigenetic" literally means "in addition to changes in genetic sequence." The term has evolved to include any process that alters gene activity without changing the DNA sequence, and leads to modifications that can be transmitted to daughter cells (although experiments show that some epigenetic changes can be reverses).
                      PLUS, you got the so-called "junk DNA" which may be the operator of the genome DNA that codes

                      http://www.genengnews.com/insight-an...stem/77899872/

                      GEN Genetic Engineering & Biolotechnology News
                      Aug 8, 2013
                      What Junk DNA? It’s an Operating System
                      Back in the old days, the general wisdom had it that introns loaded into the human genome were basically useless. While some noncoding DNA is transcribed in noncoding RNA, such as transfer RNA, ribosomal RNA, regulatory RNA, or endogenous retroviruses, others produce RNA with no known function or identified utility to the cell.

                      But over the past few years, as high-powered analytical tools and genomic information have become available, the function of introns, such as transcription factor recognition sequences, has become better understood. And, as John Stamatoyannopoulos, M.D., associate professor of genome sciences and medicine at the University of Washington, points out, while only about 2% of the human genome codes for proteins, “Hidden in the remaining 98 percent are instructions that basically tell the genes how to switch on and off." His laboratory focuses on disease-associated variants in regulatory regions of DNA.....

                      .....“In essence, these instructions are organized into millions of DNA ‘switches.’ These switches consist of strings of genetic letters, maybe 100 to 200 letters long, that can be thought of as sentences made up of short DNA words. The DNA words function as docking sites for special regulatory proteins,” said Dr. Stamatoyannopoulos.
                      source
                      Epigenetics seems to vindicate Lamarckian directed evolution, and long non-coding RNAs(LNC) used in epigenetics
                      http://www.the-scientist.com/?articl...e-Missing-Lnc/

                      THE SCIENTIST Oct 1, 2012
                      Lamarck and the Missing Lnc

                      Although biologists have generally considered Lamarck’s ideas to contain as much truth as Kipling’s fables, the burgeoning field of epigenetics has made some of us reconsider our ridicule. While no biologist believes that organisms can willfully change their physiology in response to their environment and pass those changes on to their offspring, some evidence suggests that the environment can make lasting changes to the genome via epigenetic mechanisms—changes that may be passed on to future generations.

                      Epigenetics: genome gatekeeper

                      Epigenetic changes can range from chemical modifications of histone proteins—such as acetylation and methylation—to modifications made to the DNA itself. Such changes usually cause chromatin compaction, which limits the ability of the RNA polymerase II transcription complex to access DNA, ultimately resulting in reduced messenger RNA (mRNA) and protein output. Many view epigenetics as an annotation or editing of the genome that defines which genes will be silenced in order to streamline protein production or squelch unnecessary redundancy. That annotation, they say, does not and cannot permanently change the original manuscript (i.e., DNA), but merely access to the manuscript.
                      source
                      and experiments have shown, that some evolutionary reversion is possible in as few as 5 generations, although it may take 50 and still not affect every member of a population:
                      EPIGENETIC PRINCIPLES OF EVOLUTION Nelson Cabej

                      p323
                      Evolutionary reversions in metazoan populations are not "all-or-none" but statistical phenomena only affecting certain individuals of the population per generation. In experiments on D. melanogaster, populations that have evolved in a nuber of biochemical and life history characters under stressful conditions within a few hundred generatins (several decades) in laboratory, it has been onserved that the return to the ancestral (wild-type) environment does not lead to an immediate reversion of ancestral traits and does not affect all of the individuals of the population. Reversion to ancestral, wild-type traits may take from 5 to 50 generations to occur, and only certain proportions of the population revert to the ancestral characters (Teotonio and Rose, 2000). The degree of reversion to ancestral characters for different traits also varied from complete to incomplete, and sometimes no reversion occurred at all.
                      The process of experimental evolutionary reversion of the lost ancestral traits in Drosophila followed four different patterns:
                      1. Full convergence to the ancestral character in little more than 20 generations (e.g., in the case of the female developmental time).
                      2. Initial rapid reversion with partial convergence to the ancestral trait followed by arrest of reversion (e.g., starvation resistance).
                      3. Changes that did not converge to the ancestral traits within 50 generations, and
                      4. Lack of significant changes after 50 generations (fecundity under high density) (Teotonio and Rose, 2000, 2001; Teotonia et al., 2002)
                      Due to the statistical nature of the reversion of ancestral characters, under natural conditions, evolution in the reverse takes place as a process of natural selection.

                      ON PAGE 312 IT SAID:
                      "....metazoans may retrieve these ancestral programs in a "rainy day," when the environment changes in direction of ancestral or quasi-ancestral conditions.

                      maybe some atavisms are the result of epigentic response to environment change.


                      AND there is still Allopatric speciation

                      an example of allopatric speciation shows that reproductive isolation can be achieved in 13 generations, example salmon:
                      A PDF


                      there's a ton of more epigenetic information, but I have to stop somewhere.
                      To say that crony capitalism is not true/free market capitalism, is like saying a grand slam is not true baseball, or like saying scoring a touchdown is not true American football ...Stefan Mykhaylo D

                      Comment


                      • #26
                        Originally posted by jordanriver View Post
                        what if they aren't technically "extinct"
                        according to Berkeley page on The Dinosauria
                        http://www.ucmp.berkeley.edu/diapsids/dinosaur.html

                        so if dinosaurs still exist, 'in birds', is it possible to "extract them" back out of birds:
                        source
                        This ok, but also birds existed in the Cretaceous, ~144 to 66 million years ago.



                        Michio Kaku, theoretical physicist, futurist, and a communicator and popularizer of science, host of several TV specials for the BBC, the Discovery Channel, the History Channel, and the Science Channel, on one of his many youtube videos says it's EPIGENETICS (start about 2:40 or 2:50)
                        http://www.youtube.com/watch?v=8c-EWSmOgDc

                        Epigenetics explained to non scientists like me, (but I have to watch it more than once (or twice or five times maybe), from the popular NOVA's Neil DeGrasse Tyson


                        if the genes are already there, you don't need the slow process of gene-based mutation and natural selection.
                        Epigenetics can react to the environment and change within a few generations.

                        and if you "lose" a species, maybe you can get it back , changes IN REVERSE



                        PLUS, you got the so-called "junk DNA" which may be the operator of the genome DNA that codes



                        Epigenetics seems to vindicate Lamarckian directed evolution, and long non-coding RNAs(LNC) used in epigenetics

                        and experiments have shown, that some evolutionary reversion is possible in as few as 5 generations, although it may take 50 and still not affect every member of a population:



                        maybe some atavisms are the result of epigentic response to environment change.


                        AND there is still Allopatric speciation

                        an example of allopatric speciation shows that reproductive isolation can be achieved in 13 generations, example salmon:
                        A PDF


                        there's a ton of more epigenetic information, but I have to stop somewhere.
                        True what we see today is the process of evolution in biological life in action all around us among varieties, subspecies, and closely related species. As we go back in the fossil evidence 5,000, 10,000, 100,000 1 million, back to billions of years we see this continuous process over time.
                        Last edited by shunyadragon; 09-28-2014, 09:58 PM.
                        Glendower: I can call spirits from the vasty deep.
                        Hotspur: Why, so can I, or so can any man;
                        But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

                        go with the flow the river knows . . .

                        Frank

                        I do not know, therefore everything is in pencil.

                        Comment


                        • #27
                          Originally posted by klaus54 View Post
                          I can kinda see what you're saying, but, man -- from your avatar you are one butt ugly chick.



                          K54
                          That's butt ugly DUDE, you Coke-drinking simpleton!
                          "When the Western world accepted Christianity, Caesar conquered; and the received text of Western theology was edited by his lawyers…. The brief Galilean vision of humility flickered throughout the ages, uncertainly…. But the deeper idolatry, of the fashioning of God in the image of the Egyptian, Persian, and Roman imperial rulers, was retained. The Church gave unto God the attributes which belonged exclusively to Caesar."

                          — Alfred North Whitehead

                          Comment

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