Question: Adult salamanders Metamorphing?

[454]

Could a mature neotonic, or phaedomorphic salamander metamorph? When salamanders such as a tiger salamaner, or Dicamptodon remain a "gilled adult". Can they just metamorph whenever? Could lowering water, and rising tempatures cause this?

Thanks!

 

[Jennewt]

Yes, a mature paedomorphic salamander can, in some cases, "finish" their metamorphosis later in life. This often happens, for example, when someone obtains wild-caught paedomorphic tiger salamanders. After a few months in captivity (with warmer temperature and other stresses/differences from what they had in the wild), these sals lose their gills and emerge. I don't know of other examples, but I would bet that there are others.

There are some species that are NOT capable of doing this. Necturus, for example, will never lose their gills.

Axolotls are an intermediate case. They usually stay neotenic both in the wild and in captivity, but there is the occasional adult that completes metamorphosis, for whatever reason.

 

[Azhael]

I´ll only add that species like M.alpestris or L.vulgaris can also be neotenic, but can finish the normal development any time.

 

[454]

Thanks you two!

 

[nickjwes]

Just to add to this post, some neotenic salamanders (including the axolotl) actually do not complete the metamorphosis to the "normal" adult stage because they lack the thyroid stimulating hormone which causes them to mature and metamorphose. I have read that in labs tests have been done where iodine could be injected which would stimulate production of this hormone and cause the final metamorphosis to "adulthood". I assume that there could be natural defects in salamanders causing to change as well even if they are neotenic. Also its possible that trace iodine in the water could have caused the change. I'm pretty sure thats accurate to what I read, and I hope that was somewhat helpful if not interesting to know. -Nick