How did the Armatae Bestia evolve studded plates?

Meet the following specimen of Armatae Bestia. I'd describe it, but a picture is worth a thousand words, so I'll just put one here instead (Feel free to drag it into browser window to get a much bigger picture).

As you can see, the beast has a heavily armored body. The Armatae Bestia are herbivores, and they live in sparse forests in herds, letting their armor protect them.

I've hit a slight hiccup though. When I modeled the species, I wanted it to look bad ass, and I had intended for these creatures to be hunted by those of my world in order to use the armor for shielding/weaponry. I put "studs" into the armor plates. See closeups 1 and 2 (blue circles in closeup 2 show the studs I'm talking about.

Closeup 1:

Closeup 2: (Note: Not all the studs are circled, I only circled some.)

I'm having trouble explaining how they evolved to have studs in their armor. Typically, armor is smooth in order to deflect things; Scales and shells come to mind. But I REALLY like the way the studs look, even though this thing essentially has "shells" growing on it.

What would cause a cow sized beast to evolve studs in their armor plates?

Additional notes:

• If a specific predator type of damage from a predator caused this, please detail the kind of damage the predator inflicted - there is no need to actually invent the predator, proper logic to explain why the studs would help against the predator's attack is enough.

• If weather or climate conditions could have caused this, please explain what how and why.

Slightly modified pictures for those who have trouble seeing the darker original colors.

posted about 9 years ago

Aify‭

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