Arete Posted March 6, 2014 Posted March 6, 2014 But...there is value in preserving species or their germplasm. I never said that there wasn't - in particular, implicit in maintaining the evolutionary potential of an ecosystem is maintaining maximal genetic diversity in that system. The issue arises in that there is limited funds available for conservation efforts. If you take a systems view of conservation, then for e.g. maintaining Siberian tiger populations in captivity so they do not become extinct has a cost from a limited pool available, with negligible benefit for the diversity and thus evolutionary robustness of a system. This is exacerbated exponentially for the costs involved in the revival of extinct species - in terms of conservation, rather than curiosity - what are you getting for your dollar? What ecological system are you restoring function to if the organism is never intended for wild release? How much biodiversity is each dollar buying you? The value answer immediately steers away from a species centric vision of conservation to a regional focus. An example of such a focus is the use of IBRA bio-region categories to plan a national reserve system in Australia. http://www.environment.gov.au/topics/land/national-reserve-system/science-maps-and-data/australias-bioregions-ibra#ibra Endangered species, endemic species, species richness and a large variety of other parameters are evaluated to prioritize land acquisition for an integrated reserve system. The aim being the maximize the amount of ecological and genetic diversity protected for the investment available for conservation. In contrast, the species-centrist approach to conservation generally makes qualitative and often subjective approach to selecting species of high conservation priority to invest in. While this is great for the particular organisms which are the target of such an approach, I personally question what the long term aims and goals are - I completely see the emotional aspect of it, subjective me sees the extinction of say, the Western Black Rhino as a tragedy and wishes we did more to prevent it, but pragmatic me understands that the loss of top level complexity is symptomatic of broader problems within an ecological system, and that saving charismatic species without investing heavily in protecting the entire system doesn't really achieve any long term conservation goal. As an aside, using the conservation of charismatic species to generate public interest and investment in conservation priorities is a different but related issue. There's no way you'd be able to sell biological conservation without the poster species... so you need a species-centric element to at least explain and fund conservation programs, sure. 2
chadn737 Posted March 6, 2014 Posted March 6, 2014 I never said that there wasn't - in particular, implicit in maintaining the evolutionary potential of an ecosystem is maintaining maximal genetic diversity in that system. The issue arises in that there is limited funds available for conservation efforts. If you take a systems view of conservation, then for e.g. maintaining Siberian tiger populations in captivity so they do not become extinct has a cost from a limited pool available, with negligible benefit for the diversity and thus evolutionary robustness of a system. This is exacerbated exponentially for the costs involved in the revival of extinct species - in terms of conservation, rather than curiosity - what are you getting for your dollar? What ecological system are you restoring function to if the organism is never intended for wild release? How much biodiversity is each dollar buying you? The value answer immediately steers away from a species centric vision of conservation to a regional focus. An example of such a focus is the use of IBRA bio-region categories to plan a national reserve system in Australia. http://www.environment.gov.au/topics/land/national-reserve-system/science-maps-and-data/australias-bioregions-ibra#ibra Endangered species, endemic species, species richness and a large variety of other parameters are evaluated to prioritize land acquisition for an integrated reserve system. The aim being the maximize the amount of ecological and genetic diversity protected for the investment available for conservation. In contrast, the species-centrist approach to conservation generally makes qualitative and often subjective approach to selecting species of high conservation priority to invest in. While this is great for the particular organisms which are the target of such an approach, I personally question what the long term aims and goals are - I completely see the emotional aspect of it, subjective me sees the extinction of say, the Western Black Rhino as a tragedy and wishes we did more to prevent it, but pragmatic me understands that the loss of top level complexity is symptomatic of broader problems within an ecological system, and that saving charismatic species without investing heavily in protecting the entire system doesn't really achieve any long term conservation goal. As an aside, using the conservation of charismatic species to generate public interest and investment in conservation priorities is a different but related issue. There's no way you'd be able to sell biological conservation without the poster species... so you need a species-centric element to at least explain and fund conservation programs, sure. There was a lot more context to what I said. The preservation of germplasm does not necessarily entail the preservation of a species in the wild. For example, with plants, it is possible to store seeds for decades or longer. It is possible to preserve sperm and eggs for long periods of time. While a species may go extinct in the wild, preservation of the germplasm could allow future restoration efforts. I'm not even really talking about big showy animals like black rhinos either. As I said before, I think more about plants than I do animals, and the preservation of plant biodiversity is of great interest to me. Not just because of intrinsic value, but also extrinsic as well. Such genetic diversity could be of great value in agriculture or drug development. I understand the limitation of funds, but I don't think this is such a black or white situation. Especially as you pointed out, that you need the poster species to sell conservation efforts.
overtone Posted March 6, 2014 Posted March 6, 2014 Is there any reason to assume those bones have recoverable DNA, there were not preserved by cold but by immersion in hot tar. I seems unlikely to me. They were getting useful DNA sequences from La Brea sabertooths twenty years ago and more - http://www.pnas.org/content/89/20/9769.full.pdf - it seems likely that the dramatic tech advances since then provide at least the possibility of a useful entire genome or adequate reconstruction proxy thereof. Tar provides a dry and anoxic environment. Re-establishing adequate environment for large poster species, which would be necessary for their rewilding, would very likely cover the envirnomental needs of a great many humbler ones. As well as the human beings involved. But in North America we face an unusual circumstance: the environment was in extraordinary flux at the time of first Western contact, having been very recently depopulated of its fire-setting and omnivorously predatory humans which in turn had populated the place coincidently with a major extinction of large animals which had followed hard upon the de-glaciation (oddly enough) of the continent. We may not have a "natural" environment to re-establish - those huge herds of bison, sky-blotting flocks of passenger pigeons (and trumpeter swans, according to Audobon), etc, may have been as artificial in a sense as the current tick-ridden infestation of deer hordes in the elk and bison and moose regions of Minnesota. While we're on the general subject, anyone up for cloning the DNA of some recently extinguished varieties of Homo sapiens? Aboriginal Tasmanians, say, or the people Columbus met on Hispaniola.
Arete Posted March 7, 2014 Posted March 7, 2014 (edited) The preservation of germplasm does not necessarily entail the preservation of a species in the wild. Which is one of my points. If your "conservation effort" doesn't involve the conservation of the ecological and evolutionary mechanisms associated with the organism, it efficacy for the purpose of conservation is questionable. For example, with plants, it is possible to store seeds for decades or longer. It is possible to preserve sperm and eggs for long periods of time. While a species may go extinct in the wild, preservation of the germplasm could allow future restoration efforts. Sure, but the major purpose of seed banks (at least in terms of funding and collection effort) is for food security, rather than conservation. Museum collections, tissue collections, herbariums, etc all can play a role in conservation efforts, sure - I never denied that. However, the major purpose of these facilities is generally not conservation, and if your purpose is conservation, it is an expensive route, with extremely limited returns. Restoring a nonviable species once it has already become extinct is extremely intensive - in the midst of a biodiversity crisis as we are, an ounce of extinction prevention or ecosystem fuction retention is worth a ton of restoration, in terms of money and effort. I'm not even really talking about big showy animals like black rhinos either. As I said before, I think more about plants than I do animals, and the preservation of plant biodiversity is of great interest to me. Not just because of intrinsic value, but also extrinsic as well. The title of the thread explicitly refers to animals. Hence my use of animal examples. Such genetic diversity could be of great value in agriculture or drug development. Sure, but expanding and maintaining a genetic resource is not synonymous with biological conservation. I understand the limitation of funds, but I don't think this is such a black or white situation. Especially as you pointed out, that you need the poster species to sell conservation efforts and I never said it was a black and white issue. Actually my exact words were " I think that species-centric approaches at the expense of systemic approaches are myopic." They were getting useful DNA sequences from La Brea sabertooths twenty years ago and more - http://www.pnas.org/...0/9769.full.pdf - it seems likely that the dramatic tech advances since then provide at least the possibility of a useful entire genome or adequate reconstruction proxy thereof. I wouldn't bet on it yet. The thylacine genome project was a dismal failure http://www.abc.net.au/science/articles/2005/02/15/1302459.htm and theoir samples are in a much better state of preservation than the La Brea sabertooth samples. The only sequence in genbank for Smilodon fatalis is an mtDNA fragment 132bp in length http://www.ncbi.nlm.nih.gov/nuccore/257782 which appears to come from the study you cited - so no additional saber tooth tiger DNA in 20 years. Edited March 7, 2014 by Arete 1
For Prose Posted May 7, 2014 Posted May 7, 2014 Initially, I sided with Nature magazine on the idea of bringing back extinct species as ridiculous. After I put some serious thought into it, I have concluded this might be a hasty judgement. The real implications of how the earth is changing in dramatic ways is quite evident (whether or not this is our fault remains in another thread) but solutions for these problems are few and far inbetween. At some point, as controversial as it sounds, we as a species may be better off reverting back to a former ancestral species (the mechanics of which are highly involved and quite understandably, outside of what is currently possible I believe). Additionally, species that were once better suited for extreme environments as compared to our current trend, may be what is needed for ecological sustainability. I realize that this is all mere speculation, but to quickly dismiss an idea, and idea that may hold the key to preventing the collapse of certain ecosystems in the future, is something we should avoid. Don't let ficticious movies, such as Jurassic Park, sway your thinking in something as monumental as the idea of bringing back extinct animals. This is fallacious reasoning in my eyes.
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