Does anyone have an idea on how the "Proto"morph comes about?

Yes, the true "Protomorph" is a pre-existing organism as far as we know. The Neomorphs are a result of evolution within Black Goo infected wildlife. The Black Goo seems to be somewhat of a mimic agent formulated by following and/or tampering with the Protomorph's genetic code. However, we don't really know for sure.

I see.  I hope this movie really dives into origin/creation of these creatures.     Thanks

at the moment who knows...

All we can assume is that ONE MONSTER is created at the hands of David....   most likely using the Black Goo.

The other could well be either a event that comes from after this Experiment that David has been doing...

Or it could be something that has been on Paradise prior, and maybe something David had experimented with?

So before the goo ever came about. These xenomorph like creatures existed on paradise?

It's hard to say. Will we see already mature protomorphs, or will we see the classic life cycle, and THEN David modifies it? Either way, I think the Neomorph pods will already be there by the time the Covenant touches down 

AC will likely give us 
An answer.

My guess is they are 
Creatures found on 
A different planet 
With a different life 
Cycle to the one we 
See in alien.

And that David created
the life cycle.

I think the neomorphs are what happens when black goo meets engineers and propagates the life cycle. I think David released the goo when the inhabitants of Paradise threaten earth, capture Shaw, or kill her. The protomorphs are unleashed as a result.

I believe that Billy Crudup's character will give birth to the Protomorph on board the Covenant. He is lured by David into the egg chamber as we see in the trailer, facehugged and left there. He awakes and somehow makes it back aboard the Covenant ship. 

@David007 yes, but it's clearly Walter in the cave, not David, unless he did a jungle dye job. Except for that you are probably right. Walter might watch any witnesses to the facehugging die and keep his mouth shut when Cap gets back to the ship to facilitate the impending birth of doom.

Along the lines of the protomorph existing before they arrive - the aliens as we know them I think are a creation of the engineers. The engineers have since perished through their golums. The footage we saw of them running in Prometheus verified this. Whether they attempted to recreate these creatures or they were a bi-product of the Weapon of mass destruction that is the black goo is yet to be seen. The tomb we witnessed in Prometheus seems to point to the former, though the relief image in Prometheus now seems actually eerily similar to the adult neo morph designs.

Many questions need to be answered. Most importantly I believe is that if David  created the Zeno morph by blending his "mechanical genes" with the bio goo weapon then why does this exact bio weapon creature exist in an ancient fossilized ship on an entirely different planet in an egg waiting to infect Dallas's crew? - Remember those events occur what, only about 25 years later right? I hope fox and Ridley are doing true world building here. The inherent problem is that while it seems like Fox wants to create an "adult" Star Wars franchise - this universe was never developed to the extent that Lucas or Tolkien took the time to do. They are all working off of a small slasher film (the original Alien). Cameron probably has more Alien universe concept work, but he is deep in Avatar.

I am very excited for the film and greatly enjoyed Prometheus - we'll see!

A lot of good theories.  That was an interesting point about possibly david luring the captain into the facehugger room.  I read about that somewhere and that definitely looks like that's what is going on in the trailer. 

And look like he isolates the Captain (Crudup) to himself and alone. I have to wonder where are the other crew members and it would make sense. The other crew members would not know what happened to him and when Crudu awakes, David can make up and story about what happened. Captian does not know he has been hosted. 

Well plans can evolve over time...

We dont know what Life Cycle or Speed of growth we would be seeing here, i would assume the Eggs are created prior to the Covenant Crew arriving.

I would assume the Spores have been there for a while too, and also prior...

The case is now, which of these two events did David play a role in or did he play a role in both? or neither.

The Question comes down to if David unleashed the Goo on Paradise either on the Engineers, or by accident after a Crash.

Or if a previous event had taken its toll on Paradise, that left the Eggs or Spores or both.

The concept works give us a clue... many think this is Davids work shop.... but where does he get Paper from? and Pen? What about those stands he places the Experiments on?

How does he keep the Experiments in good shape, yet some are now Skeletons..?

Hoe does he create a Xeno to then draw it without getting killed?

How does he take one related Organisms head off?

You see for those with a keen eye, as i mentioned before the Skulls are New Born Babies...

Does this mean David experimented on Baby Humans? Shaw cant birth a Baby without Human Sperm. Or Engineer Babies and what of the Bird ones?

They could be experiments by David but how/where would he get Birds and Babies?  Maybe on Covenant?

Who knows....

My Theory?  They are artistic inspirations...

Used to look at Anatomy of those things to help design Monsters for the movie...

However.... a few of these concepts where Baby-head Like Xenos each a bit different, and so maybe these could have been planned concepts dropped... or indeed may relate to some experiments David had done...

But looking at how the Goo worked, i assume to get something like them would require a early stage Pregnant Female with a at the time Human Fetus.

But a few things we know for sure:

1: the juggernaut on LV-426 has been there a long time. Weyland industries had received the transmission before Prometheus left. The Xenos on that ship have not been modified by David in any way.

2. Paradise is not nor will it ever be  LV-426. LV-426 orbits the same gas giant as LV-223.  It's not an uncharted planet and it definitely wouldn't require hyperspace travel to reach from LV-223.

3. Any differences in the Xenos now could be explained by forced evolution from the Engineers, regular evolution, or just living on a planet with breathable air and life everywhere. Their life cycle hasn't changed in any observable way.

4: therefore the only beastie David could have a hand in unleashing is the Neomorphs.  He most likely did that by spreading black goo around Paradise. If he did that for giggles, everyone on the covenant is in deep trouble. If he did it to try to protect earth or Shaw, there is at least hope that he won't try to screw everyone over in the name of discovery. 

Well he could have a hand in RE-creating the classic Xeno. He could use the purely organic Protomorph as a template 

That's fair, depending on his motives. I want him to be a good guy in this movie, but I have nothing solid to back that up with. I just know he has 0 impact on the organisms on LV-426

A bit far-fetched but would make for an interesting twist: could it be that Cudrup's character actually knows that he is going to be facehugged? He might be alligned with W-Y's interests and might be convinced by David/Walter that this is the only way to bring the xeno into Covenant without the others knowing and that the robots can extract the creature while inside the ship with no damage for him. That would explain Fassbender's passive stance on the picture and also why the movie producers would be willing to place in the trailer/movie something that at first sight looks so much as a repetition of Alien.

As it turns out, there's no way to safely remove the Xenos after implantation.they create a sac that puts tendrils throughout the surrounding organs. Removing the embryo would remove the sack and the host dies anyway. The look on Crudup's face does not communicate anything to me more than "what the f*** is that?" When the egg opens. 

Here is a theory...

the xenomorphs are already there. ( as a result from an engineer with a bio-suit getting facehugged ) they are in the distance and when covenant shows ups it brings them in. The neomorphs are a result from the black goo being exposed to a specific environment. I also think ( as I've stated before in other posts) that the corporation knows more than the story line is leading us to believe.

the covenant crew are just geunea pigs.

i also think there is a bigger threat than us humans as to why the engineers are/were trying to weaponize the black goo ( which is a chemical ) not organic in its first stage ( according to the wetland-yutani website)

Shastacyclone  .   I like that theory, but if the engineers got facehugged, then where did the facehuggers coms from. I mean where did the eggs come from.  Maybe I just don't understand enough about it.  I'm learning everyday lol..