Of all the scientific improbabilities in the Star Trek universe, of all the scenarios we see, this one is by far the most mind-numbingly horrendous in my opinion. OK, so my willing suspension of disbelief goes far enough to cover that Tom breaks Warp 10. It goes further to accept that his medical condition or the lack of sufficient protection (or both) lead to dire consequences. What I can't accept is the Doctor's explanation that Tom (and later the Captain) are *evolving*, only to turn into hairless aquatic mammals that give birth over a span of only 3 days. And the Doctor can (and does) reverse it! Yay, Doctor!
Don't waste your time on this one.
Don't waste your time on this one.