My pleasure; please let me know what you learn.

Please let me know if you need any further information. Good luck, enjoy and please keep me posted.

Best regards, Frank Indiviglio.

Thanks, I see what you are asking. Changes in our understanding of salamander evolution occur very frequently these days due to advances in genetic research and new fossil evidence. Most taxonomists consider the Asiatic salamanders in the family Hynobidae to be among the most primitive, or at least, closest to the ancestral form. The family Plethonontidae is considered to be the most “advanced” because many have reduced their dependence on water for breeding; Red-backed salamanders, for example, lay eggs on land, guard them, and the eggs hatch into tiny salamanders, skipping the larval stage altogether. This may allow them to colonize entirely new habitats, as happened when reptiles evolved hard-shelled eggs.

But “primitive” and “advanced” are relative. Sirens are considered primitive by many taxonomists (some place them in a different order from salamanders than altogether) yet they have gills, lungs and can breathe through their skin as well; they can also aestivate for months during droughts; therefore they can survive where others cannot. The “advanced” Plethodontids breathe entirely through their skin, and lack both lungs and gills; they are therefore limited to damp habitats on land (oxygen will only pass through wet skin) –so in that sense are less advanced than the Sirens.

Primitive as taxonomists use it mainly means (as I understand it) “first evolved”…but we really do not have enough evidence at this time to be sure of where each family fits.

I touch on some of this in my book Newts and Salamanders, but things change daily so please continue to write in with questions or with new information you have found. Deullman and Traub’s Biology of the Amphibians goes into evolution in detail, but again much will have changed since it was written.
Please let me know if you need any further information. Good luck, enjoy and please keep me posted.

Best regards, Frank Indiviglio.

Thanks and regards.

My pleasure; glad you enjoyed.

Your question is a very interesting one that still vexes biologists. It’s not within my area of expertise, but from all I’ve read there is strong evidence that a fish or fish-like creature did evolve into the first amphibian. This is most easy to see, at least to my eye, in the lungfishes, especially the Australian Lungfish. However, there is better evidence that another group of fishes actually gave rise to the amphibians.

You might also enjoy these articles on Early Amphibians/Missing Links and Early Terrestrial Amphibians.

Please let me know if you need any further information and please keep the interesting notes coming. Good luck, enjoy and please keep me posted.

Best regards, Frank Indiviglio.

Thanks for the most interesting questions.

In salamanders, the Vomeronasal organ is mainly used to detect chemicals or chemical molecules in the substrate. It is most highly developed in terrestrial salamanders, such as the Red Backed Salamander and other Plethodontids. In fact, Red Backs and some others have small grooves (naso-labial grooves) that are used to transport chemical ques from the earth to the vomeronasal organ (which is located within the snout). They also have a head tapping behavior that seems to help in the uptake of these molecules. Females check scat piles left by males in this manner, and are able to determine the male’s fitness/health. The vomeronasal organ is reduced in size and importance in paedomorpic, fully aquatic species such as Hellbenders and Amphiumas. It is intermediate in size, at least in those species studied, in salamanders that split their time between land and water, such as the California and Marbled Newts.

The Olfactory system/”sense of smell” is used to detect airborne scents. It seems more highly developed in terrestrial species. However, it is also housed in the snout, and differentiating between its role and that of the vomeronasal system can be difficult (and not so many people seem to try!). I know from experience that fully aquatic species such as the Siren and semi aquatic newts can definitely detect non-living food via scent – as their vomeronasal systems are not well-developed, perhaps they rely upon olfaction? Please see this article for more on the distinction between the 2 systems.

The lateral line system is a series of pits along the sides of the body that contain sensory cells/organs, similar to that evolved by fishes. It is highly developed in aquatic species such as Hellbenders, Mudpuppies, Sirens, Japanese Giant Salamanders, Amphiumas and Mexican Axolotls (in some, such as Axolotls, the line is easy to see). It is likely present in aquatic larvae as well. Aquatic frogs, such as Surinam Toads, African Clawed Frogs and Lake Titicaca Frogs also possess a lateral line system.

Please let me know if you need any further information. Good luck, enjoy and please keep me posted.

Best regards, Frank Indiviglio.

I’ve set you a direct email as well; thanks for your interest and kind words. I look forward to helping out in any way I can.

Besrt regards, Frank

My partner and I have recently started up a business in South Africa of collecting and breeding tarantulas, in particular the more endangered specimens. We are also wanting to send 10 percent of our hatchlings back to originating countries and help with the conservation and re-establishment of endangered species of tarantula back into the wild.
Due to your extensive knowledge and willingness to help with advice we would really greatly appreciate a correspondent with whom we can communicate via e-mail, facebook, skype or blackberry messenger about our various experiences, findings, tarantula updates etc and also perhaps get your advice.
Would it be possible to communicate with you directly?

Would greatly appreciate it and thanks very much in advance for your assistance and correspondence.

Yours sincerely
Storm