Defenses of dinosaurs without obvious weapons

[Infinity Blade]

What are some defenses some dinosaurs without obvious weapons or the likes (ornithopods, oviraptorosaurs, etc.) could have utilized? Discuss.

Here's an interesting one: someone once described the hands of hadrosaurs as "biological boxing gloves". I do have a problem though, the front limbs seem a bit too slender for that IMO.

Of course, nothing here is 100% proven and is speculation (albeit some may have a bit of reason behind them).

[fish]

Same thing as the less defensive animals of today do when confronted by predators: Living in herds can decrease the chance of an individual getting picked off by an attacker. Fleeing. Fighting with bites, slams, tail slaps etc as a last resort.

[Runic]

Running like the wind.

[Fragillimus335]

The video, White Tip's Journey does a great job of showing raptor/oviraptor interaction!

[Vodmeister]

Amphicoelias didn't really have any weapons, but it dwarfed most dinosaurs around it. For smaller dinosaurs without weapons, "run for your life" seems like the only rational option.

[Deleted]

Depends on the relative sizes of predator and prey. Smaller prey can only flee, prey around the same rough size ballpark of the predator can live in herds for defense, flee, or fight(probably even gang up on the predator).

Larger prey can go herd or fight(if fleeing isn't a practical option, which is often the case for very large prey like large sauropods, so they have no choice but to fight)

When dinosaurs without obvious weapons go for the fight response, it can be kicking(either with rear or front legs), shoving, ramming, tail slamming, probably even biting, pecking(for the beaked ones), etc.

[spinosaurus1]

i imagine ornithomimids being able to defend themselves similarly to cassowaries or ostriches against similar sized opponents.

[creature386]

Defending shouldn't be hard for most of them, especially the runners. They don't need to kill their predators, they just need to make sure they survive. A well placed kick during a chase can already be enough to ruin the predator's attempt of catching it's prey.

[Infinity Blade]

I remembered on Carnivora, kicking and tail swiping can be two ways hadrosaurs physically defended themselves. Some people also believe that their chewing behavior could mean a fairly high bite force, though, there doesn't appear to be anything deadly about the jaws themselves, so I think it's less likely (unless the beak had sharp keratin edges). In the OP, I mentioned someone who thinks of hadrosaur manus to be "biological boxing gloves", though their forelimbs are pretty slender.

Sauropods could possibly use their foot claws on predators shorter than them in height.

[theropod]

Those biological boxing gloves are an interesting hypothesis. I’m not saying it is realistic, I’m not very well informed about the manus of hadrosaurs.

However consider this; that those forelimbs were slender may have allowed them to attain very high striking speeds. Ergo, it wouldn’t be necessary to produce large forces over extended periods of time, as long as the manus can be accellerated sufficiently and hit the opponent with sufficient force.
That may reduce stress on most of the forelimb, but one would have to know whether the hands themselved display adaptions (e.g. particularly compact bones etc.) to withstand the collision forces.

In general; most animals will attempt to flee or hide, especially the small ones. Size and raw strenght offers sufficient protection after a certain body mass is attained. Mid-sized to large herbivores are commonly found in herds. Many dinosaurs were probably r-strategists, producing huge amounts of offspring with a high mortality rate and quick growth.
Funny enough, in many dinosaurs we have exceedingly prominent anatomical adaptions for defense (e.g. horns, thagomizers, blade-like spikes, osteoderm armour, clubs, claws, whiptails...).
Apart from those obvious things, there are of course all those exotic means of deterring predators, for example spitting or containing some poisonous, acidic or disgusting substance, mimicries, and who-knows-what kind of non-preserved elements.

[Infinity Blade]

I can see where he's coming from on the "biological boxing glove". From what I know, hadrosaur manus had fused fingers and it just looked like a "lump of soft tissue" (for lack of a better phrase). That could potentially deliver blunt trauma.

[Runic]

I'd love to see a hadrosaur box a T Rex XD that would be a kodak moment if it won.

[Infinity Blade]

Stygimoloch spinifer isn't exactly something that has unobvious weaponry, but its horns look nasty.







Given its dome doesn't look that big either, I wouldn't be surprised if the horns were the main weapon of this pachycephalosaur. Well, if it can lower its head down that far.

[theropod]

Its likely just a younger ontogenic stage of Pachycephalosaurus, so its adult stage had fairly large domes but small horns.

[creature386]

Even if it was, there could have been animals similar to it at adult stage and there such defense mechanisms would apply to.