Well, they stole from Larry Niven...

Message:

"So many alien cross-breeds...How would the biology work?!?"

It doesn't. Never did. Spock had copper based blood for crying out loud.

But -- and you may remember this Next-gen episode -- there was this species a long time ago which, when it knew it was on the verge of extinction, sent out seed ships with their DNA to all the planets of the galaxy. The reason all the Trek aliens are humans with forehead and nose makeup isn't the practical production reality of needing aliens on a budget which emote better than animatronics and animation, but because we've all got that common ancestor thing going on. Y'know, that peace and brotherhood can't we all get along wokeness which dates back in Trek to the 1960's.

Anyways, Niven did that first -- but, at least in his Known Space universe when the ancient aliens all died in a war, they didn't panspermia-bukkake the galaxy... Nope, all the latter sentients evolved on Slaver farm planets. Yup, the galaxy evolved from homogenous foot algae/yeast.

From the above we can see Ridley Scott's Prometheus was doubly redundant.

Although, unlike Prometheus and Next-Gen, Niven tended to write characters that didn't have to behave like total idiots to move the plot along.

Yours,