Here is the only bit I can remember from cross-human language comparison, not cross-species:
https://en.wikipedia.org/wiki/Speech_tempo (searched: different languages speaking rate) (Edit: information density and speech rate)
So my first question is about types of "spoken languages"?
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from searching, "types of languages" "click languages":
* African languages and linguistic typology - https://www.acsu.buffalo.edu/~jcgood/jcgood-AfricaTypology.p...
* Language Classification: History and Method - https://edisciplinas.usp.br/mod/resource/view.php?id=2225588
Anyone have a speech-to-text and POS-tagger yet for dolphins' language morphology/-ies?
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Deciphering the Dolphin Language - http://neuronresearch.net/dolphin/pdf/Dolphin_language.pdf
An assumption can be made that the CNS of the dolphin employs a frame time similar to humans, nominally 30 milliseconds. As a starting point, it is reasonable to assume that a typical phoneme is three to five times longer than 30 ms based on experience with human languages. A complication arises because of the multiple sources of sound within the dolphin’s nasal passages, recalling that the larynx of the dolphin is not in its throat (the passage along which food is ingested). These multiple acoustic sources suggest the dolphin can achieve an equivalent of the unique “throat singing” of the Inuit and Tuva people of Asia. Throat singing is also known as overtone singing. Wikipedia provides a good description of throat singing. In Dolphin, the equivalent is clearly nasal singing. Nasal singing in dolphin may be even more extensive.
As a starting point, the acoustic range of dolphin sounds (other than its forward focused echolocation sounds) potentially useful in communications (language) extends from about 2000 Hz to at least 80,000 Hz (with whistles extending up to about 40,000 Hz). In seeking to understand Dolphinia or Truncates, it makes no sense to restrict our analyses to frequencies that the human can hear. Nor is it rational to limit the dolphin’s language to either a tonal or a stressed structure.
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Interpreting the acoustic pulse emissions of a wild bottlenose dolphin - http://aquaticmammalsjournal.org/share/AquaticMammalsIssueAr...
The study of acoustic signals and the supposed spoken language of the dolphins - https://www.sciencedirect.com/science/article/pii/S240572231...
I hope some researcher(s) will put out organized videos of dolphins chatting alongside audio spectrograms. Remember the Enigma story, every message had certain words in it and was likely to have certain ones in certain places at certain times from certain senders to certain receivers... Certainly.