Comments on: To Salvage One Endangered Fish Species, Scientists Consider Breeding It with Another http://blogs.discovermagazine.com/80beats/2012/11/21/to-salvage-one-endangered-fish-species-scientists-consider-breeding-it-with-another/ Mon, 22 Apr 2013 21:34:00 +0000 hourly 1 http://wordpress.org/?v=3.4.2 By: Matt Pedersen http://blogs.discovermagazine.com/80beats/2012/11/21/to-salvage-one-endangered-fish-species-scientists-consider-breeding-it-with-another/#comment-34766 Matt Pedersen Fri, 23 Nov 2012 05:35:16 +0000 http://blogs.discovermagazine.com/80beats/?p=41534#comment-34766 From a genetic viability standpoint I can completely understand the concern; the population size is potentially too small for long-term viability. However, the examples provided regarding other "hybrids" to "save a species" are not valid parallels. The Florida "hybridizing" was actually the introduction of genetics from the Texas subspecies to the Florida population; we might argue that before European settlement, these populations may have been connected? Even if they weren't, they are still taxonomic the same species - Puma concolor.- http://content.usatoday.com/communities/sciencefair/post/2010/09/new-blood-perks-up-florida-panther-population/1#.UK8Gloc0V8E By the same token, the White Rhino "hybridization" was again, at the time, believed to occur between two subspecies populations of what was at that time considered the same species. - http://www.rhinoconservation.org/2010/06/07/northern-white-rhino-breeding-plan-to-begin-with-hybrids/ In this case, the taxonomy so far is quite clear - The two species in question ARE just that, considered unique species. I'll leave the taxonomy to the scientists who determine these things, but it is fair to say that if a new species is introduced, and does successfully hybridize, this does in fact wipe out the Desert Hole Pupfish from a species perspective. You can't "undo" a hybrid. So really, the question is being framed as "do we have SOME sort of pupfish vs. no pupfish at all"...but no, we are not "saving a species", we are creating something new instead. From a genetic viability standpoint I can completely understand the concern; the population size is potentially too small for long-term viability. However, the examples provided regarding other “hybrids” to “save a species” are not valid parallels.

The Florida “hybridizing” was actually the introduction of genetics from the Texas subspecies to the Florida population; we might argue that before European settlement, these populations may have been connected? Even if they weren’t, they are still taxonomic the same species – Puma concolor.- http://content.usatoday.com/communities/sciencefair/post/2010/09/new-blood-perks-up-florida-panther-population/1#.UK8Gloc0V8E

By the same token, the White Rhino “hybridization” was again, at the time, believed to occur between two subspecies populations of what was at that time considered the same species. – http://www.rhinoconservation.org/2010/06/07/northern-white-rhino-breeding-plan-to-begin-with-hybrids/

In this case, the taxonomy so far is quite clear – The two species in question ARE just that, considered unique species. I’ll leave the taxonomy to the scientists who determine these things, but it is fair to say that if a new species is introduced, and does successfully hybridize, this does in fact wipe out the Desert Hole Pupfish from a species perspective. You can’t “undo” a hybrid. So really, the question is being framed as “do we have SOME sort of pupfish vs. no pupfish at all”…but no, we are not “saving a species”, we are creating something new instead.

]]> By: Mike http://blogs.discovermagazine.com/80beats/2012/11/21/to-salvage-one-endangered-fish-species-scientists-consider-breeding-it-with-another/#comment-34765 Mike Wed, 21 Nov 2012 18:57:59 +0000 http://blogs.discovermagazine.com/80beats/?p=41534#comment-34765 The threat to the Devil's Hole pupfish is that the groundwater level is dropping due to overextraction of water for agriculture. How would replacing the species with a hybrid change that? Also the Devil's Hole pupfish isn't "critically endangered", it's listed at the lower threat-level "vulnerable", so hybridizing is not necessary to 'save' the fish. In short, this project isn't necessary and doesn't solve the problem. The threat to the Devil’s Hole pupfish is that the groundwater level is dropping due to overextraction of water for agriculture. How would replacing the species with a hybrid change that?

Also the Devil’s Hole pupfish isn’t “critically endangered”, it’s listed at the lower threat-level “vulnerable”, so hybridizing is not necessary to ‘save’ the fish.

In short, this project isn’t necessary and doesn’t solve the problem.

]]> By: floodmouse http://blogs.discovermagazine.com/80beats/2012/11/21/to-salvage-one-endangered-fish-species-scientists-consider-breeding-it-with-another/#comment-34764 floodmouse Wed, 21 Nov 2012 15:25:39 +0000 http://blogs.discovermagazine.com/80beats/?p=41534#comment-34764 Hybrids are generally more vigorous than pedigree animals. Captive breeding programs are a form of artificial selection, which is not always a bad thing, but it sounds like the pupfish have their own ideas about the best way to make babies. I say give the endangered animals their own choice out of the possible available mates, and let nature do its stuff. Hybrids are generally more vigorous than pedigree animals. Captive breeding programs are a form of artificial selection, which is not always a bad thing, but it sounds like the pupfish have their own ideas about the best way to make babies. I say give the endangered animals their own choice out of the possible available mates, and let nature do its stuff.

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