A word that means the opposite of "menagerie"

I'm trying to find a couple antonyms of the word "menagerie". Some word that means a group of clones, or a collection of virtually identical things. I haven't been able to find one. Can you help me?

EDIT: this word must fit:

"Mr. Smith had a ______ of birds. They all looked exactly the same."

(Must imply the birds being the same w/o second sentence)

See my comment for Richard Kayser, above.

In the military, the attempt in Basic Training is to eliminate differences between soldiers among the ranks. Individuality is discouraged, except for the exceptional standout, who ends up in a key unit, such as the Green Berets, Navy SEALs, etc.

Everyone else is, by design, made to look just like the next guy. There are many opinions as to why this is, but the fact is, it is this way. Every man gets the same uniform. The haircuts are the same, even the glasses are identical, except for the prescription.

So, maybe an army term based on size would be suitable, with an adjective preceding it to further describe the collection.

For example, some size words: squad, platoon, brigade, army... "Mr. Smith had a squad of birds. They all looked exactly the same." "Mr. Smith had a platoon of birds. They all looked exactly the same." "Mr. Smith had a brigade of birds. They all looked exactly the same." "Mr. Smith had an army of birds. They all looked exactly the same."

Adjectives to describe the collection: unorganized, disciplined, undisciplined, etc. "Mr. Smith had an unorganized squad of birds. They all looked exactly the same." "Mr. Smith had a disciplined squad of birds. They all looked exactly the same." "Mr. Smith had an undisciplined squad of birds. They all looked exactly the same."

Sorry but no such word exists and it would be much more useful for you to completely rephrase the question, than to pursue it as originally posed.

“Menagerie” does always mean a group of creatures but it's by no means always assumed that they’re different creatures.

“Menagerie” does have more to do with the place where they are kept or cared for than the creatures themselves.

Either way, asking for an “opposite” or “antonym” of “menagerie” or any word like it, is rather like asking for an “opposite” or “antonym” of “people” or of “fish”.

My point is that that kind of thinking should be recognised as a dead end, and turned away from.

A word for a group or herd or bunch or flock of birds that all looked exactly the same is such a different thing, it’s very unlikely to be found from that perspective.

Unless I and others have completely misunderstood, the concept is much too broad to be expressed in a simple sentence such as "Mr. Smith had a ______ of birds. They all looked exactly the same" - the more so if the answer “Must imply the birds being the same w/o second sentence.”

Aside from the original question, can you please rephrase “They all looked exactly the same" to express your meaning in different words?