Talk:Tailed frog

Latest comment: 5 months ago by Uncreative54 in topic Use of term primitive

Use of term primitive

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I am confused about the use of the term primitive in this article. The family is called primitve because it is the sister group to all other frogs, but it is not clear that the actual characteristics described as primitive are in fact shared with the common ancestor. In particular, it seems unlikely that the particular antibacterial secretions of this family were primitive and lost in all other frogs - it seems more likely that this is a derived characteristic. The source presents these chemicals as derived characteristics that have undergone evolution within this family.

It seems that because the family has been denoted primitive that all of its charactistics have been assumed primitive. I think it is questionable to describe a family as primitive because it is a sister group to a wider group (are the chelicerata primitive within the arthropods, for example?). I don't know if the number of vertebrae is a primitive characteristic as is claimed in the article - this would be interesting, but the assertion is made without any reference. Anropa (talk) 18:41, 24 September 2023 (UTC)Reply

Necro-ing this, but doing a brief survey of the ncbi for secondary loss of traits, floating ribs and vertebrae count do appear to have been present in fossil frogs and secondarily lost in modern, extant frogs.
The secretions are definitely not a trait primitive to modern frogs and I'm confident enough tgat I will edit that to read that it is unique to Ascaphus.
As for lacking the ability to vocalize, I havent searched enough to find whether or not the Ascaphus limitations are the primitive state, so I will separate that out. Uncreative54 (talk) 02:51, 24 June 2024 (UTC)Reply
Just to update for posterity, the presence of the middle ear via the existence of the columnella is the ancestral state. We understand it as a plesiomorphy due to the presence of the columnella in fossil anurans. So, though they are basla sister taxa, Ascaphus lacking the middle ear and the ability to vocalize is a secondary loss. Uncreative54 (talk) 03:03, 24 June 2024 (UTC)Reply