Reviewing, Revising, and Finalizing Prehistoric Animals and Dinosaur Ecology

[Cleon]

3.5 statblocks do (sometimes) allow for Colossal creatures with a Space larger than 30 ft.

the 3.5 revision to Epic Handbook, gives the devastation vermin, and the biggest Abomination, a 50 ft space.

Oh blast, I'd forgotten about the Devastation Vermin, and they're SRD so there's nothing to stop us using them as a precedent.

also- the larger specimens of Diplodocus (Diplodocus hallorum, AKA Seismosaurus), may have weighed a bit more than 16 tons.

True enough, but I was statting up a Diplodocid of nondescript size (e.g. a 80-90 foot long, 10-15 ton Diplodocus carnegiei), not a particularly large one which would be Gargantuan or maybe even Colossal.

By the way, I've decided to increase the bite reach of my 3E Diplodocid stats. Its definitely longer-necked than a standard sauropod.

Which reminds me, I've forgotten to include really long necked sauropods like Mamenchisaurus.

All well and good- but they list Diplodocus as being revised downward from 5500 kg to 4000 kg.

Since when did anyone think it was 5500 kg?

That does seem way too low. They do appear to be getting carried away with the air-sacs. I know some of the Diplodocids had extensive weight-saving adaptations, but if they're talking about a 70+ foot long individual that doesn't sound right.

There's a similar situation with recent weight estimates for large Pterosaurs, some of the weight estimates for a large Pterosaur like Quetzalcoatlus are so low you wonder how the poor beast would be able to land or walk without collapsing like a deck of cards. I've been using the higher weight estimatesuggested in Witton & Naish's paper A Reappraisal of Azhdarchid Morphology and Paleoecology. They seem credible, and a more robust interpretation is better suited for a "D&D version" of a big Pterosaur.

Anyhow, I'd better go and add the revisions to my Sauropod post. I haven't started on the bipedal Prosauropoda yet.

 

[hamishspence]

Dinosaurs

Diplodocus and Apatosaurus are quite short necked (20-22 ft) compared to some of the others- a 20 ft reach (if on a 20 ft base) is plenty- for them. Barosaurus, etc can have longer reach.

(the highest figure I've seen for Mammenchisaurus is for a recent exhibit- with a length of 115 ft and a neck length of about 50 ft- longer, by a narrow margin, even than Supersaurus. )

(one source of the 115 ft length):

http://dinogoss.blogspot.com/2009/07/my-sauropod-is-bigger.html

I wondered if the 5.5 tonne estimate was due to the newspaper getting it wrong- since Naish, Wedel, etc, who were the ones stressing the air sacs of sauropods- were also the ones giving the 10-12 ton estimate.

I was thinking of the 80-90 ft diplodocid as big enough to justify a 20 ft base.

Placed on one of those- its feet- roughly 15 ft or so apart from front of forefooot to front of hind foot- and its back height- around 15 ft high- is fairly comparable to one of the Gargantuan dragon models.

If Gargantuan was to begin with Diplodocus carnegii - move through Barosaurus, Apatosaurus, Diplodous hallorum, Mamenchisaurus, Supersaurus, etc, then that should cover a pretty fair range-

from the 70 ft Apatosaurus, to the 112 ft Supersaurus and 115 ft Mamenchisaurus.

And with the 160-190 ft Amphicoelias fragillimus, filling the Colossal slot.

(If it existed, that is )

Plus- there are sauropods in the 50 ft long, 8-10 ton weight range (ideal for Huge) and a few, so small, they might, even as adults, be Large.

on Herrerasaurus- it's place is still being debated- its not clear if it's a theropod, or if it evolved prior to the split- but the most recent opinions tend toward it being not a theropod.

 

[hamishspence]

how many kinds of sauropod?

We have Generic Sauropod (probably the camerasaurs, largest prosauropods, non-armoured titanosaurs, and the chunkier diplodocids such as Apatosaurus. These can run from Large at adult stage, to high-end Gargantuan (and, if Bruhathkyosaurus exists, colossal as well)

We have Tall brachiosaur-type Sauropods- which range from the only Large Europasaurus, to the Huge Euhelopus (actually a titanosaur, but looks exactly like a mini-brachiosaurus) to the Gargantuan Brachiosaurus altithorax and Giraffatitan brancai, to the borderline Colossal (at least by height) Sauroposeidon.

We have the whip-tailed sauropods- some with very long necks, like Supersaurus, some with short necks and even long spines on them (Dicraeosaurus)

and we have the armoured sauropods- like Saltasaurus.

But are these the only ones? Should there be a "club-tailed sauropod" group- exemplified by Shunosaurus?

Or a "spine-necked" group- including the aforementioned Dicraeosaurus.

I think Mamenchisaurus also has a very small relative- also with a neck nearly as long as the body and tail. These could be the "long-necked" group, separate from the whip-tails.

EDIT: I've checked- Omeisaurus is one example of a smaller longneck- up 50 ft long- 4 tons in weight- but with a neck up to 30 ft long. Big.

Erketu- with its 24 ft neck, may also fit- despite not being closely related:

http://www.newcritters.com/2006/03/21/erketu-ellisoni-the-looooooong-necked-sauropod/

A possible listing of major groups- a bit like with the theropods:

Generic Sauropod (mostly titanosaur)
Tall-shouldered Sauropod (mostly brachiosaur)
Armoured Sauropod (titanosaur)
Spine-necked Sauropod (Dicraeosaurus and a few others)
Long-necked Sauropod (Mamenchisaurus and a few others)
Whip-tailed Sauropod (mostly diplodocoid)
Club-tailed sauropod (Shunosaurus and a few others)

 

[Cleon]

Oh blast it, the Large Ankylosaurs attack bonuses are all wrong - I forgot to change them after copy-and-pasting the basic Huge Ankylosaurus. And I didn't put in the correct age for Gargoyleosaurus.

Better fix it.

EDIT: Okay, fixed those mistakes - and a bunch of other errors I hadn't noticed before.

More cheerfully, I've finished writing up Gastonia, so added it to the post.

 

[hamishspence]

Thyreophorans compared to sauropods

It is sort of funny- that we've just been statting out spiked, armoured- and club-tailed thyreophorans-

and it turns out- that there are spiked, armoured, and club-tailed sauropods.

EDIT: the ankylosaur and stegosaur stats look good. Lots of special abilities to represent how heavily protected they were.

Scelidosaurus could probably be represented by taking a Large one, and trimming back most of the powers- since its armour was less, and its spikes were very short.

When you mentioned prosauropods, it might work more simply to divide the group into:

"Bipedal sauropodomorphs" which are mostly prosauropods, and at least one very early sauropod- Anchisaurus- which was bipedal-

and "Quadrupedal sauropodomorphs" which include the largest prosauropods- the ones which look very like smallish sauropods. Most of these would fit in "generic sauropod".

Bipedal ones (as adults) can probably run from Small (Thecodontosaurus) to Large (Plateosaurus) and the minimum size for a baby specimen is probably Diminuitive (Mussaurus- 6 inches to base of tail, 15 inches long overall)

It is possible Thecodontosaurus had smaller babies- but we probably do not need Fine dinosaurs.

 

[Cleon]

Diplodocus and Apatosaurus are quite short necked (20-22 ft) compared to some of the others- a 20 ft reach (if on a 20 ft base) is plenty- for them. Barosaurus, etc can have longer reach.

My current D&D stats give a 30 ft neck reach and a 45 ft tail reach for an average 90 foot long (Huge) Diplodocus, and a 20 foot neck-reach and 40 foot tail-reach for an 80 foot long (Gargantuan) Apatosaurus.

Those seem in the right ballpark for me.

(the highest figure I've seen for Mammenchisaurus is for a recent exhibit- with a length of 115 ft and a neck length of about 50 ft- longer, by a narrow margin, even than Supersaurus. )

Yes, I've seen 14 metre (49 foot) quote in quite a few popular dino-sources. It sounds more scientific in SI units.

And with the 160-190 ft Amphicoelias fragillimus, filling the Colossal slot.

(If it existed, that is )

I'd include stats for a Colossal Sauropod even if we knew for a fact they never reached that size. They're proverbially big creatures, and the AD&D universe seems to be far more forgiving about the biomechanics of oversized animals.

on Herrerasaurus- it's place is still being debated- its not clear if it's a theropod, or if it evolved prior to the split- but the most recent opinions tend toward it being not a theropod.

I was inquiring more as to what stats we should give it than its taxonomical relationships, I know they're at that uncertain age when the Ornithischians split up.

Basically, would Herrerasaurs use a Medium or Large "Classic Carnosaur" or "Gracile Carnosaur" stats, or would they require a set of "Primitive Carnosaur" stats. They're pretty close in build to a "Gracile Carnosaur" (e.g. a Dilophosaurus) so I'd be tempted to just use those stats. I guess there's an argument for creating a "Primitive Carnosaur" with a slightly lower speed and/or a tad less effective bite or claw attacks, since its feet, claws and jaws are relatively unspecialized, although my current preference would be to create a "Primitive Carnosaur" stats by giving them a somewhat less effective feat selection (e.g. drop Weapon Focus (bite) for Toughness, cutting their racial bonuses and giving them Skill-boosting feats instead).

 

[Cleon]

Generic Sauropod (mostly titanosaur)
Tall-shouldered Sauropod (mostly brachiosaur)
Armoured Sauropod (titanosaur)
Spine-necked Sauropod (Dicraeosaurus and a few others)
Long-necked Sauropod (Mamenchisaurus and a few others)
Whip-tailed Sauropod (mostly diplodocoid)
Club-tailed sauropod (Shunosaurus and a few others)

As far as my stats are concerned whiptails are a standard feature of most of the sauropods.

I thought about including spine-backed sauropods, but most sauropod spines were fairly small and would probably not do much as far as the animal's D&D stat go, so I decided to consider them to be for display or species recognition of a standard generic Sauropod, or just part of the armour of an Armoured sauropod in the case of the most exaggeratedly spiny genera like Augustina.

A similar line of thought made me decide not to have separate stats for a club-tailed sauropod. Many sauropods had some sort of reinforced tail tip, usually a bony rod for "whip-tailed" sauropods. I suspected a Shunosaurus's rather small tail club would be functionally the same, so would be covered by the current tail-slap damage.

Although while we are on the subject of sauropod tail-slaps, I was tempted to give most sauropods some kind of stunning blow attack with their tail.

 

[Cleon]

When you mentioned prosauropods, it might work more simply to divide the group into:

"Bipedal sauropodomorphs" which are mostly prosauropods, and at least one very early sauropod- Anchisaurus- which was bipedal-

and "Quadrupedal sauropodomorphs" which include the largest prosauropods- the ones which look very like smallish sauropods. Most of these would fit in "generic sauropod".

Erm, that's what I'm in the process of doing. I've already covered the quadrupedal generic prosauropods, but haven't started statting the bipedal ones.

 

[hamishspence]

herrarasaurus

It is comparable in weight and length (around 350 kg and 20 ft long) to the larger gracile theropods such as Gojirasaurus- at up to 350 kg it is more lightly built than Dilophosaurus but more heavily built than the slim ceratosaur Elaphrosaurus.

Though- it could be a "less specialized" group of its own- maybe with Eoraptor representing Small size, and Staurikosaurus Medium size.

On sauropods:

the "tail three times as long as Space" formula is an interesting one- but if the dinosaur is going on a base a bit wider than the space defined by its four feet, it may be excessive.

Apatosaurus doesn't really have a larger body than Diplodocus, after all, just a thicker-boned one.

Maybe the two could be split up more by Hit Dice and Strength- rather than Size.

EDIT:
I've had a look at the skeletal drawings- given the relatively short neck (compared to Barosaurus or Supersaurus) and given the closeness in size of Diplodocus carnegii to Diplodocus hallorum- (90 ft, compated to 98 ft) a possible option could be:

Neck length- same as space
Tail length- three times the space

Diplodocus- 20ft neck reach, 20 ft space, 60 ft tail reach- 100 ft long.

Smaller diplodocid- 15 ft neck reach, 15 ft space, 45 ft tail reach- 75 ft long.

Barosaurus, Supersaurus- etc could go in with the proportionally long-necked ones like Mamenchisaurus- and have a different set of proportions.

Something along the lines of: tail being equal to twice Space, neck being equal to Space.

This gives 120 ft for a sauropod with a 30 ft Space, and 80 ft for a sauropod with a 20 ft space.

an 80 ft Barosaurus and a 120 ft Supersaurus or Mamenchisaurus don't stretch credibility too much.

Amphicoelias altus- another diplodocid- the smaller and much more complete cousin of Amphicoelias fragillimus- falls at around 82 feet long.

 

[hamishspence]

Space/Reach advancing slower than dimensions

Of course, if Wizards had not made the Space/Reach categories for a creature advance slower than the dimensions, we might not have these problems:

If Space/Reach had doubled every time, the way Height/Length does, after Large, it would have looked something like this:

Large: Space 10 ft, Reach 5-10 ft
Huge: Space 20 ft, Reach 10-20 ft
Gargantuan: Space 40 ft, Reach 20-40 ft
Colossal: Space 80 ft, Reach 40-80 ft

Which would have allowed most of the big theropods, right up to Spinosaurus, to fit into Huge size, as well as Diplodocus:

And most of the biggest sauropods, to fit into Gargantuan size- right up to Argentinosaurus.