Zidartha
New member
I’ve put together a collection of some of the findings from Blackburn College over the last few years together with my musings on the subject.
In 2009 Blackburn College established the Floater Phenotype SICB - 2009 meeting - Abstract Details
For the hobbyist, one particular finding may be of interest. It is usually assumed that poor husbandry is the cause of a floating axolotl. Once poor water, environment, and diet have been ruled out as the cause of a floating axolotl’s stress, one may conclude it belongs to this phenotype. Many hobbyists will add to the animal’s stress by fridging or re-homing in very shallow water. This research also concluded that the ‘Floater’ had a better survival rate in deeper water: “In still, shallow water (5cm), recovery was slow and irregular; 8 of 29 (28%) BC-Floaters recovered by nine months. In 25cm deep water (with turbulence generated by a hanging power filter) 42 of 44 (93%) six month-old BC-Floaters reverted to a normal body posture within 10 days.” So perhaps leaving well enough alone, may be the way to go.
In 2011 they presented their research on the Blackburn College Floater axolotl, which they established as a breed of salamander which possess a genetic mutation that causes them to float on their backs. -- http://blackburn.edu/documents/BiologyTrip_web.pdf Thus the common floater that many hobbyist have come to be acquainted with may actually be a genetic mutation rather than due to poor husbandry.
Blackburn College has continued to research the floating phenomena. The original question was whether or not these animals are holding their breath because they are choosing to do so or because they can't use their lungs to breathe in and out.
An early test demonstrates the later:
“The axolotls take a deep breath (which makes them buoyant enough that the float on their back) and then they hold their breath… and keep holding it… and keep holding it… sometimes for up to a YEAR! (In the mean time, they’re using their gills to get oxygen.) The research is to see if these axolotls (now called the "Blackburn College Floaters") are choosing to stay floating on their backs for so long, or if they are unable to exhale.
To test this, they put some of the floating axolotls in special water that had very low levels of oxygen dissolved in it. Without oxygen in the water, the axolotls can't use their gills, and would have to depend on their lungs. But the floaters didn't exhale to get a new breath; instead they just got agitated (as if they were suffocating) until they were placed back in normal water.” -- A Breath of Fresh Air?
So it would seem that the Floating axolotls simply can not use their lungs owing to their genetic mutation.
This mutation seems to have little or no advantage to the individual axolotl; however, one must keep in mind that an axolotl female can lay up to 1000 eggs at a time. My hypothesis: Perhaps this mutation creates ‘sacrificial lambs’ early in the juvenile development cycle. These Floaters would be ‘sacrificial lambs’ so to speak as they would be easily picked off by birds, fish, and other such predators, which would help protect the rest of the colony at large. Imagine your little Floater sitting in the middle of Lake Xochimilco. There would be little chance for survival – and that’s the point. It would be evolutionary utilitarianism at its best.
Any thoughts?
k.
In 2009 Blackburn College established the Floater Phenotype SICB - 2009 meeting - Abstract Details
For the hobbyist, one particular finding may be of interest. It is usually assumed that poor husbandry is the cause of a floating axolotl. Once poor water, environment, and diet have been ruled out as the cause of a floating axolotl’s stress, one may conclude it belongs to this phenotype. Many hobbyists will add to the animal’s stress by fridging or re-homing in very shallow water. This research also concluded that the ‘Floater’ had a better survival rate in deeper water: “In still, shallow water (5cm), recovery was slow and irregular; 8 of 29 (28%) BC-Floaters recovered by nine months. In 25cm deep water (with turbulence generated by a hanging power filter) 42 of 44 (93%) six month-old BC-Floaters reverted to a normal body posture within 10 days.” So perhaps leaving well enough alone, may be the way to go.
In 2011 they presented their research on the Blackburn College Floater axolotl, which they established as a breed of salamander which possess a genetic mutation that causes them to float on their backs. -- http://blackburn.edu/documents/BiologyTrip_web.pdf Thus the common floater that many hobbyist have come to be acquainted with may actually be a genetic mutation rather than due to poor husbandry.
Blackburn College has continued to research the floating phenomena. The original question was whether or not these animals are holding their breath because they are choosing to do so or because they can't use their lungs to breathe in and out.
An early test demonstrates the later:
“The axolotls take a deep breath (which makes them buoyant enough that the float on their back) and then they hold their breath… and keep holding it… and keep holding it… sometimes for up to a YEAR! (In the mean time, they’re using their gills to get oxygen.) The research is to see if these axolotls (now called the "Blackburn College Floaters") are choosing to stay floating on their backs for so long, or if they are unable to exhale.
To test this, they put some of the floating axolotls in special water that had very low levels of oxygen dissolved in it. Without oxygen in the water, the axolotls can't use their gills, and would have to depend on their lungs. But the floaters didn't exhale to get a new breath; instead they just got agitated (as if they were suffocating) until they were placed back in normal water.” -- A Breath of Fresh Air?
So it would seem that the Floating axolotls simply can not use their lungs owing to their genetic mutation.
This mutation seems to have little or no advantage to the individual axolotl; however, one must keep in mind that an axolotl female can lay up to 1000 eggs at a time. My hypothesis: Perhaps this mutation creates ‘sacrificial lambs’ early in the juvenile development cycle. These Floaters would be ‘sacrificial lambs’ so to speak as they would be easily picked off by birds, fish, and other such predators, which would help protect the rest of the colony at large. Imagine your little Floater sitting in the middle of Lake Xochimilco. There would be little chance for survival – and that’s the point. It would be evolutionary utilitarianism at its best.
Any thoughts?
k.
