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Why has the Chattahoochee DH so dissapointing?

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  • Originally posted by trout1980 View Post
    The major problem for the shoal bass is not some stocked trout actually but hybridization with largemouth, kentucky and alabama basses.

    At least below MF and in the Flint River.


    If the hybrid offspring are retroactively viable then they aren't a different species, but a strain difference. Similar to the way a Doberman and a poodle aren't different species.

    If the hybrids are common and sterile.... Well that might be a problem, but only inasmuch as within strain/species reduction is suppressed or somehow not preferred. That would seem odd to me. But I don't know much about fishy reproduction.


    Sent from my iPhone using Tapatalk

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    • Originally posted by splatek16 View Post
      If the hybrid offspring are retroactively viable then they aren't a different species, but a strain difference. Similar to the way a Doberman and a poodle aren't different species.

      If the hybrids are common and sterile.... Well that might be a problem, but only inasmuch as within strain/species reduction is suppressed or somehow not preferred. That would seem odd to me. But I don't know much about fishy reproduction.


      Sent from my iPhone using Tapatalk
      If I am not mistaken I believe the shoal bass situation is in the middle somewhere.

      They certainly hybridize, and then keep hybdrizing. They're really pretty close genetically is my understanding.

      I hadn't thought about it in the way you suggested, but if they keep hybdridizing and moving on down the chain the almost seem more like different "breeds" of black bass.
      I like em big fat and sloppy.

      Comment


      • Potentially a ring species situation?
        -skunked

        Warning: all posts should be assumed to contain sarcasm and misinformation unless stated otherwise. The opinions shared are not necessarily those of the poster.

        Comment


        • Originally posted by I_got_skunked View Post
          Potentially a ring species situation?
          First off, sorry for all the typos in my last post, jeez, I have to proof-read better.
          Second, yeah, I guess it could be the case of ring speciation. Although, in my understanding of "typical" ring speciation, it's a geographical barrier that represents the "hub" of the ring. That being said, ring speciation would suggest that some of the variant hybrids are actually intermediate forms between the two ends (or reproductive barriers) of the ring. That would be a really cool finding if, what I am calling the hub of the ring is some aspect of the water, water column, etc. I need to learn more about various bass populations to know this and I am sure someone already knows this. Alternatively, in a population of closely related organisms living in absence of a geographical border, but still showing variants that differ meaningfully, it could be frequency-dependent selection.

          The idea that the hybrids or "new" species of bass are intermediate forms of the ends of the ring are particularly intriguing to me, because they would in essence represent transitional species. It wouldn't be the first time that a drastic introduction of an environmental change (i.e. damming rivers, human impact) have impacted the course of evolutionary change.

          Again, all conjecture here on my part, I study humans and know little about fish, but the processes should all be the same/similar!

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          • Originally posted by splatek16 View Post
            First off, sorry for all the typos in my last post, jeez, I have to proof-read better.
            Second, yeah, I guess it could be the case of ring speciation. Although, in my understanding of "typical" ring speciation, it's a geographical barrier that represents the "hub" of the ring. That being said, ring speciation would suggest that some of the variant hybrids are actually intermediate forms between the two ends (or reproductive barriers) of the ring. That would be a really cool finding if, what I am calling the hub of the ring is some aspect of the water, water column, etc. I need to learn more about various bass populations to know this and I am sure someone already knows this. Alternatively, in a population of closely related organisms living in absence of a geographical border, but still showing variants that differ meaningfully, it could be frequency-dependent selection.

            The idea that the hybrids or "new" species of bass are intermediate forms of the ends of the ring are particularly intriguing to me, because they would in essence represent transitional species. It wouldn't be the first time that a drastic introduction of an environmental change (i.e. damming rivers, human impact) have impacted the course of evolutionary change.

            Again, all conjecture here on my part, I study humans and know little about fish, but the processes should all be the same/similar!
            That actually sounds dead nuts. Alabama bass and shoal bass are in some drainages that flow into each other.
            I like em big fat and sloppy.

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            • Originally posted by browniez View Post
              Twenty pages. Let's do it.
              I don't want to disrupt your goals but if folks prefer, they can adjust their "User CP" for number of posts per page. I'm only on page five.

              click on "User CP" at top left of page
              click on "Settings & Options"
              click on "Edit Options"
              click on "Thread Display Options"
              click on "Number of Posts to Show Per Page"
              click on "40"

              Some good must come of this dead horse of a thread that has evolved into a goat. Not that there is anything wrong with that. Maybe the IT folks can figure out how NGTO could get a fraction of a penny for each view.
              Last edited by THE EG; 02-21-18, 11:17 AM.
              If this were rocket science most of us wouldn't be doing it. - Terry Creech

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              • Originally posted by THE EG View Post
                I don't want to disrupt your goals but if folks prefer, they can adjust their "User CP" for number of posts per page. I'm only on page five.

                click on "User CP" at top left of page
                click on "Settings & Options"
                click on "Edit Options"
                click on "Thread Display Options"
                click on "Number of Posts to Show Per Page"
                click on "40"

                Some good must come of this dead horse of a thread that has evolved into a goat. Not that there is anything wrong with that.
                Goat = greatest of all time
                -skunked

                Warning: all posts should be assumed to contain sarcasm and misinformation unless stated otherwise. The opinions shared are not necessarily those of the poster.

                Comment


                • Originally posted by browniez View Post
                  That actually sounds dead nuts. Alabama bass and shoal bass are in some drainages that flow into each other.


                  That's what I thought,. Which makes me think strain differences.
                  I'd need to see the data on genetics for species divergence


                  Sent from my iPhone using Tapatalk

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                  • It seems to have picked up

                    There was a lull for a few pages but pages 15-19 seem to be coming on strong with logic and conjecture that has made this thread awesome to read. So busy I just caught up! And there is so much good info I need to reread it to absorb more! Nice work guys!

                    Next post we will hit page 20
                    #JBNavy

                    "Everyday is a new life to a wise man."
                    -Chinese Proverb

                    “At sunrise everything is luminous but not clear.”
                    -Norman Maclean

                    "We are what we hunt."
                    -PH

                    Comment


                    • Originally posted by splatek16 View Post
                      If the hybrid offspring are retroactively viable then they aren't a different species, but a strain difference. Similar to the way a Doberman and a poodle aren't different species.
                      I've been studying hybridization of fish (sunfish of the genus Enneacanthus, and rainbow and Yellowstone cutthroat trout), birds (Yellow- and Red-shafted Flickers), and plants (basin- and mountain-big sagebrush) for my entire career. The Biological Species Concept is a nice ideal (different species do not interbreed), but the real world is far more complicated.

                      Smallmouth and shoal bass had an allopatric (perhaps parapatric) distribution before humans started moving fish around. There were no opportunities for them to hybridize until recently. Even if they do hybridize on occasion, it doesn't mean that they violate the Biological Species Concept. Moreover, shoal bass and smallmouth bass aren't one another's closest relatives. Smallmouth bass and spotted bass are one another's closest relatives (according to mtDNA) and they usually maintain their distinctions because they live in different habitats. Shoal bass and largemouth bass are one another's closest relatives.

                      We've known for a century that many members of the Centrarchidae (black bass and sunfish) hybridize without fusing into hybrid swarms. Still, they may on occasion fuse into a single hybrid swarm. I've seen firsthand that hybrid swarms often occur in disturbed habitats. In New Jersey, it was in ponds disturbed by agriculture, with sunfish of the genus Enneacanthus in New Jersey. Introducing smallmouth bass into the Chattahoochee Drainage constitutes a disturbance in itself. It is not a fair test of the Biological Species Concept.

                      In Idaho, I had the pleasure of collecting West slope cutthroat trout and rainbow trout (steelhead) with federal fisheries biologists. The two species maintained their distinctions in the main Lochsa River, but when steelhead juveniles were planted above an impassable waterfall on a tributary, they freely interbred with the resident cutthroats. By the time we sampled the stream several years after the initial introduction of steelhead, the population contained multi-generational hybrids and parentals. It was a mess. In fact, my icon for NGTO is one of those cutthroats.

                      Does anyone know if the smallmouth-shoal bass hybrids are fertile?

                      John

                      Comment


                      • See if you can download this paper on the Evolutionary History of the Black Bass Genus (Micropterus sp.), by Near et al.

                        http://www.bioone.org/doi/pdf/10.1554/02-295

                        There are other papers that are more recent than this, but this one has DNA analysis of all of the main species of Micropterus and a couple of nice phylogenetic trees. Since this paper, though, some populations of M. punctulatus (spotted bass) have been discovered to be different species (e.g. Alabama bass).

                        John

                        Comment


                        • Originally posted by jgraham140 View Post
                          I've been studying hybridization of fish (sunfish of the genus Enneacanthus, and rainbow and Yellowstone cutthroat trout), birds (Yellow- and Red-shafted Flickers), and plants (basin- and mountain-big sagebrush) for my entire career. The Biological Species Concept is a nice ideal (different species do not interbreed), but the real world is far more complicated.

                          Smallmouth and shoal bass had an allopatric (perhaps parapatric) distribution before humans started moving fish around. There were no opportunities for them to hybridize until recently. Even if they do hybridize on occasion, it doesn't mean that they violate the Biological Species Concept. Moreover, shoal bass and smallmouth bass aren't one another's closest relatives. Smallmouth bass and spotted bass are one another's closest relatives (according to mtDNA) and they usually maintain their distinctions because they live in different habitats. Shoal bass and largemouth bass are one another's closest relatives.

                          We've known for a century that many members of the Centrarchidae (black bass and sunfish) hybridize without fusing into hybrid swarms. Still, they may on occasion fuse into a single hybrid swarm. I've seen firsthand that hybrid swarms often occur in disturbed habitats. In New Jersey, it was in ponds disturbed by agriculture, with sunfish of the genus Enneacanthus in New Jersey. Introducing smallmouth bass into the Chattahoochee Drainage constitutes a disturbance in itself. It is not a fair test of the Biological Species Concept.

                          In Idaho, I had the pleasure of collecting West slope cutthroat trout and rainbow trout (steelhead) with federal fisheries biologists. The two species maintained their distinctions in the main Lochsa River, but when steelhead juveniles were planted above an impassable waterfall on a tributary, they freely interbred with the resident cutthroats. By the time we sampled the stream several years after the initial introduction of steelhead, the population contained multi-generational hybrids and parentals. It was a mess. In fact, my icon for NGTO is one of those cutthroats.

                          Does anyone know if the smallmouth-shoal bass hybrids are fertile?

                          John
                          That's the critical question - is are the hybrids sterile? Right?
                          Hybridzation happens all over in the animal kingdom, think about the Rhaboon (rhesus macaque and baboon) and the humanzee (human and chimp,
                          The issue for speciation, in my reading is the degree to which hybrids form new (relatively isolated) reproductive parameters.

                          That article, which I was able to download and skim, suggested allopatric speciation (ie due to geographical isolation). Enter drift and voila(ish). Migrant gene flow due to transplants either legally or via bucket biologists could change gene flow in a way where the 'new' hybrids are the species.

                          I'd be interested in chatting more about this because these conversations really interest me. I again repeat: I am no fish biologist and study human neuroscience and evolution. Similar, ideas persist about hybridization of hominid ancestor populations, right? I mean get your DNA tested for "how much H. neandertalensis you are; I'm 1.6%, apparently). <-- That debate rages on in the literature and the truth probably lies somewhere in the opportunity for migrant genes to drive the population changes. In relatively isolated, or those that were isolated for longer (relative to others) periods of time, you'd expect strong drift and thus further deviations in the phylogeny.

                          Food for thought, that's for sure.

                          Comment


                          • Is genetic leakage really that bad? Statistically speaking most hybrids are sterile, but if this type of hybrid is viable and can reproduce, it increases the gene pool. Doesn't seem like it'd hurt anything other than the perpetual obsession of humans classifying things into pretty lines and boxes. I understand the concern of "tainting" a resident and uncommon species. However, in most cases a bigger gene pool, evolutionarily speaking, is beneficial in the long run... and we must keep in mind any type of speciation takes a long time given an adequate population size (barring any type of bottleneck).

                            Comment


                            • I wouldn't want to see shoal bass driven to extinction through genetic swamping. Because they have such a limited range in the Apalachicola and Chipola Drainages, it is a distinct possibility. We simply don't know how much introgession (flow of genes into the shoal bass gene pool) is happening, from either smallmouth bass in the Chattahoochee or spotted bass in the Flint.

                              Increased genetic variation isn't always a good thing.

                              John

                              Comment


                              • Originally posted by Sighter View Post
                                Is genetic leakage really that bad? Statistically speaking most hybrids are sterile, but if this type of hybrid is viable and can reproduce, it increases the gene pool. Doesn't seem like it'd hurt anything other than the perpetual obsession of humans classifying things into pretty lines and boxes. I understand the concern of "tainting" a resident and uncommon species. However, in most cases a bigger gene pool, evolutionarily speaking, is beneficial in the long run... and we must keep in mind any type of speciation takes a long time given an adequate population size (barring any type of bottleneck).
                                One group with lots of genetic leakage are the North American canids: gray wolf, coyote, red wolf, and eastern wolf. Recent evidence from Brigette vonHoldt's research group at Princeton University suggests that red wolves and eastern wolves are hybrids between gray wolves and coyotes. Is it all one species, including domestic dogs?

                                John

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