Starting with the big picture question, no, definitely not. There is an interesting unanswerable question of how the human ability to physically produce speech developed. There is a related unanswerable evolutionary question about how humans evolved to enable whatever special mechanisms we have for perceiving speech sounds. There have been numerous stabs at advancing evolutionary conjectures, perhaps Fitch The evolution of language would be a good first read, just bear in mind that he makes stuff up about language the same way that linguists make stuff up about evolution.
Dropping the evolutionary question, the next and more-answerable unanswerable question is "how do humans produce each speech sound?". To partially paraphrase the question, what is the theory of phonetics? Recall that the IPA is a conventional linguists abstraction that tells linguists how they should transcribe particular instances in an actual language, which stands for a very wide range of actual productions.
The IPA charts actually contain partial hypotheses as to that mechanism, in the form of descriptions like "voiced uvular implosive", "voiceless retroflex spirant", "close-mid front rounded nasal vowel" and so on. This partially tells you how we make them, although again only to a certain degree of precision.
The next step would be to assemble all knowledge about muscular contractions, for example "what muscle do you use to raise the tongue?". This question is covered at a basic level in any good intro course in speech and hearing science or phonetics. (Example: how do you breathe? Who cares? Well, breathing is the power source for speech). Of course there is no textbook that takes you from utter ignorance to state-of-the-art knowledge of speech anatomy, so this is a reading program, not an online resource.
Ultimately you might encounter a physiological study that looks at retroflex consonants in Hindi versus Malayalam or pharyngeals in Arabic versus Tigrinya. Typically, though, such studies can only investigate "what do the bits of superficial anatomy do", and not "what contracts, resulting in these movements".
There are some electromyographic studies that address the anatomical endpoint question about particular muscles contracting. Lips are relatively easy, laryngeal muscles are very difficult (kids! don't do this at home!). We mostly know how English speakers produce their sounds at the muscular level.
The quest is not over yet, because there is higher-level brain control over muscular actions. The jaw is an active contributor to production of speech sounds. It can be mechanically blocked: and if it is, other muscles can compensate, and this happens quick enough that there can't be a feedback loop from receptor neurons up the the grammar for a quick recompute then back down to the lips and tongue. There seems to be a plan, and it's not all stored entirely in the brain.
You can voluntarily make your tongue do fairly exact and rapid contractions, in a manner that vastly outstrips the ability of other animals. Obviously, there must have been some sequences of evolutionary changes that resulted in human speech-anatomical voluntary control compared to what chimpanzees can do. But basically, this is in the realm of the "just don't know right now".
