“Theory” of Evolution? ... It’s only a barely plausible Hypothesis. Within a species there has been some observed adaptation but never has one species been observed to transform into a new species.
What we're seeing behind this particular curtain that's being pulled back is how credentialed academics have been able to promulgate falsehoods throughout the system and get their wrong-headed "theories" taught for decades if not centuries in schools of all levels, long after contrary evidence gets purposely subverted by these same academicians.
There are many such fiefdoms that are amazingly and successfully resistant to the assimilation of new, factual information.
What we think we know is in large part wrong and a big reason is that so-called scientists (and others, e.g., archaeologists, art historians, etc.) are able to hold sway to marginalize very credible reports, often by well-trained observers.
A very good book on topics that elucidate such problems is, "Everything You Know is Still Wrong," by Lloyd Pye.
There are at least 7 or 8 examples of populations which have become different species.
Why so few? Because few scientists are interested in the question.