Reviewing, Revising, and Finalizing Prehistoric Animals and Dinosaur Ecology

[hamishspence]

Strength

Working out what the "appropriate" Str for a creature is, can be tricky. The closest thing to a guideline seems to be how much a creature can lift without being encumbered.

Given the slimmer build, I think spinosaurs can get away with having a lower Str for their size, than tyrannosaurs.

Remember that at 8 tons it's only half the minimum normal weight for a Gargantuan creature.

On sharks- like crocs, a 20 ft shark is not all that heavy- closer to 1 ton than 2. Possibly the Huge Shark statblock could be adjusted to make the Large shark, as with the crocodiles, at the beginning of the thread.

I see 20 ft as perfect for a Large shark (10 ft space, 5 ft reach, 5 ft tail reach) 35 ft as ideal for a Huge shark (15 ft space, 10 ft reach, 10 ft tail reach)

Carcharocles species, excepting the much larger Carcharocles megalodon, could be Huge. Megalodon, being much chunkier than a great white (the weight estimates for a 70 ft megalodon are around 100 tons) could be from Gargantuan to Colossal.

a 70 ft Colossal megalodon could be 30 ft space, 20 ft reach, 20 ft tail reach.

 

[hamishspence]

The "Length = Space + Reach fore and aft" method, applied to whales:

Estimates for rorqual whales- at the large end of each whale's size range:

Blue Whale: 30 ft head slam, 40 ft Space, 40 ft tail slam
Fin Whale: 30 ft head slam, 30 ft Space, 30 ft tail slam
Pygmy Blue Whale: 20 ft head slam, 30 ft Space, 30 ft tail slam
Sei Whale: 20 ft head slam, 20 ft Space, 20 ft tail slam
Bryde's Whale: 15 ft head slam, 20 ft Space, 15 ft tail slam
Humpback Whale: 15 ft head slam, 20 ft Space, 15 ft tail slam
Eden's Whale: 10 ft head slam, 15 ft Space, 15 ft tail slam
Minke Whale: 10 ft head slam, 15 ft Space, 10 ft tail slam

The other baleen whales:

Bowhead: 20 ft head slam, 30 ft Space, 20 ft tail slam
Right Whale (all regions): 20 ft head slam, 20 ft Space, 20 ft tail slam
Gray Whale: 15 ft head slam, 20 ft Space, 15 ft tail slam
Pygmy Right Whale: 5 ft head slam, 10 ft Space, 5 ft tail slam

At the bottom end, weight stops being important. It doesn't really matter that a whale weighs 3 tonnes- what matters is how long it is, and 16-20 ft long is not really long enough fot a Pygmy Right Whale to be huge.

 

[Cleon]

On sharks- like crocs, a 20 ft shark is not all that heavy- closer to 1 ton than 2. Possibly the Huge Shark statblock could be adjusted to make the Large shark, as with the crocodiles, at the beginning of the thread.

Not really. Crocodiles are a good deal slimmer than many species of big sharks. Things like threshers (Alopiidae) are possibly as light or lighter by length, because of their elongated tails, but a tiger shark or great white is several times the weight of a crocodile of the same length. E.g. a 13 foot Great White could weigh 2000 pounds or so, a crocodile that heavy would likely be approaching 18 feet long.

20 feet long is extremely big for a great white, being about the upper range of its size, and I believe a fish that size would weigh 4000 pounds or more, although from the little reading I've done there seem to be so few records of great whites that big it's hard to tell for sure.

Anyhow, adjusting the sizes of the Large and Huge sharks a bit like I did for the Crocs is probably what I'd do. We could call them a Medium / Big / Large shark, and then have a "Giant Shark" for the Huge variety.

I see 20 ft as perfect for a Large shark (10 ft space, 5 ft reach, 5 ft tail reach) 35 ft as ideal for a Huge shark (15 ft space, 10 ft reach, 10 ft tail reach)

Those seem too high. A 500 pound shark is probably only around 10-12 feet long, A run of the mill great white (2000-2500 pound?) is ~13-15 feet. I'd probably compress the SRD stats to make the Medium shark a "Big Medium" and the SRD Huge shark "Very Large" and possibly tweak the Hit Dice a bit, something like:

Big Shark (200lb, 6-8') - 3HD, Str 13
Large Shark (500lb, 10-12') - 5HD, Str 17
Very Large Shark (1500lb, 14-16') - 7HD, Str 21
Huge Shark (4000lb, 20-24') - 10HD, Str 25

They could also do with having a better Con than the SRD gives them - it's significantly behind the standard advancement rate, and I have read a good many anecdotes about some sharks being hard to kill.

A 35 foot long lamniform shark (presumably a Carcharodon/Carcharocles megadon) should weigh something of the order of 32,000 pounds - that's more Gargantuan than Huge!

Carcharocles species, excepting the much larger Carcharocles megalodon, could be Huge. Megalodon, being much chunkier than a great white (the weight estimates for a 70 ft megalodon are around 100 tons) could be from Gargantuan to Colossal.

a 70 ft Colossal megalodon could be 30 ft space, 20 ft reach, 20 ft tail reach.

I don't think there's any reason to think C. megalodon was "much chunkier" than a great white. There is little fossil evidence apart from teeth and jaws, so there's little solid proof of what form the body takes. Great whites have very robust builds for lamniform sharks, so there's a fair likelihood that megalodon had a somewhat slimmer, more average body, shape than Carcharodon carcharias - although being much bigger it obviously would be heavier.

The 70 foot length estimate sounds a bit optimistic to me (let along the 100 foot+ claims that are floating about). 50 feet is probably a more reliable guess for a megalodon's length.

 

[hamishspence]

Megalodon

They found vertabrae as well as teeth and jaws, and the teeth discovered are big.

While early estimates got the jaws wrong, thus oversizing it considerably, later ones, based on the largest teeth discovered, do make it pretty hefty.

http://en.wikipedia.org/wiki/Megalodon

Megalodon had smaller cousins around 30 ft long or so. These were the ones I was thinking of for Huge.

http://en.wikipedia.org/wiki/Carcharocles_angustidens

On great whites- the lengths given here:

http://en.wikipedia.org/wiki/Great_white

are 13-17 ft long for an average to large adult, and 1500-2400 lb.

A 13 ft long Great white should be around 1500 lb, and a 17 ft one 2400 lb. Not all that hefty.

Compare with an orca:

http://en.wikipedia.org/wiki/Orca

16 ft Orca- 3 tons. 32 ft orca- 11 tons.

This would seem to suggest that (given that orcas are chunkier than great whites) a really big Great White, a la Jaws 2, would not, in fact, be gargantuan- if an orca the same size, is both much heavier, and well short of the Gargantuan weight minimum.

Flawed as Wikipedia can be, a bit of cross-referencing does show that the 100 ton estimates for Megalodon aren't especially "overweight" so to speak.

 

[hamishspence]

Source for chunky megalodon

Reconstructing Megalodon

Having done a few checks, 100 tons does look a bit overweight- other estimates look more like 60 tons for the 70ft version.

Still- the general consensus does seem to be that it was chunkier than its smaller cousin.

Also, after a lot of online digging, the high figures for great whites seem to be:

20 ft, 4200 pounds.
21 ft, 4800 pounds.

I'm not sure where people are getting 5000+ pound figures from- maybe ones which have been caught after heavy feeding?

http://www.swordfishingcentral.com/great-white-shark-facts.html

I notice that Wikipedia figures sometimes look like they've been edited, such as "Estimates of up to 2 tons, but a maximum measured weight of 2.2 tons" Which is rather oddly phrased.

The above site had a more logically phrased example: "Estimates of up to 2 tons, but a maximum measured weight of 1.75 tons"

Also- the length to weight ratios seem to vary a lot (regional differences?) The largest well authenticated one I've found details of, was the Alf Dean 1959 specimen- 16' 10", 2664 lb. Yet specimens of comparable length in other places are claimed to be 4000 lb or more.

Comparing the Alf Dean Specimen to Yai, the heaviest crocodile in captivity, puts Yai as longer, but not by much- Yai was fairly close in weight in 1989 (1114 kg or 2465 lb) when the Guinness Book of Records accepted the record, but was 19' 8".

 

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On comparing Great Whites to megalodons

Great whites seem to vary a lot in proportions.

The 1959 Alf Dean specimen (16.8333 ft, 2664 lb)

appears to be much slimmer than than 1986 California specimen (17.6 ft, 4140 lb):

http://www.elasmo-research.org/education/white_shark/overview.htm

Scaling from the Alf Dean specimen produces a 35 ft shark that would weigh around 11.97 short tons.
But scaling from the 1986 California specimen produces a weight of 16.28 short tons for a 35 ft shark.

And 53.39 short tons for a 52 ft megalodon- which is almost exactly what the heavyweight estimates for a 52 ft megalodon give.

So, one could say, that megalodon is not chunky compared to a white shark- if it is one of the exceedingly chunky California white sharks.

 

[Cleon]

Megalodon had smaller cousins around 30 ft long or so. These were the ones I was thinking of for Huge.

Still seems a bit on the big side for a "basic" Huge shark, so I'll stick to my preference for around 20 feet and 4000 pounds for such a beast.

One problem to bear in mind is that many of the weights quoted for large animals are likely to be estimates. Unless you have a set of industrial-grade scales handy, it's exceedingly difficult to weigh animals as large as great whites or orcas.

A 13 ft long Great white should be around 1500 lb, and a 17 ft one 2400 lb. Not all that hefty.

Compare with an orca:

Killer Whale - Wikipedia, the free encyclopedia

16 ft Orca- 3 tons. 32 ft orca- 11 tons.

Some of those figures seem a little dubious. From my limited reading 3 tons (metric) is a reasonably average weight for a female orca of about 6 metres (20 feet) long, and its quite possible to have 2400 pound white shark 15-16 feet long.

While I certainly think orcas are somewhat stockier than great whites, my suspicion is that there's some overlap in sizes & weights - i.e. some chunky 16 foot Great White probably weigh the same as slim 16 foot orcas.

Similarly a 32 foot 11 ton Orca is not that far off from your projected 35 foot 11.97 (short) ton "Alf Dean" scale Great White. It would appear to me that such a big orca would equate to an individual with a lot of HD Advancement in 3E D&D terms. The SRD orca advances to Gargantuan, so I would not feel many pangs of guilt making a shark of similar size Gargantuan as well.

As for Gargantuan sharks, obviously that's unrealistic for any living species with the exception of whale sharks (and even that would be an "Advanced" specimen in 3E terms, with an average Rhincodon typus being Huge sized and with fewer Hit Dice). I'd probably start Gargantuan sharks somewhere around a nice round 40 feet in length.

Anyhow, I'll probably post a few new dinosaurs soon, so we can start arguing about something else.

 

[hamishspence]

weighing

Sharks caught in fishing contests, even big ones, do, I think, get weighed pretty accurately- possibly a winch built for the purpose?

That said, 4000 pounds (and anything from 17 to 21 ft long) is pretty reasonable for a Huge animal- it just gives it a rather short reach. Which could possibly be made up for, by removing either tail slap or bite (a whale shark wouldn't try and bite, a Great White wouldn't do tail slaps)

The figures usually given for the biggest whale shark caught (free-swimming specimens have been reported as rather bigger) was 41 ft long and estimated 15 tons. A good place to start Gargantuan at.

One thing I have noticed about WoTC creatures- hit dices doesn't correspond all that well to weight. A 12 HD Gargantuan sperm whale-shaped creature, with a length given as 60 ft (Elsewhale, in Planar Handbook), seems decidedly low, given just how heavy a sperm whale actually is.

Compare to an 18 HD T. rex.

Same applies to Str- if Str 35 is normal for a Gargantuan sperm whale, a Huge dinosaur should have a much lower Str. Or a Gargantuan one, if it's weight is fairly close to the Huge dinosaur. Or just boost the Str of the whale, if it is under-strength.

If I was to stat out a 52 ft long, 47 tonne Gargantuan megalodon, I'd give it rather more than MM2's 20 HD. It is one big beast.

And I might consider putting Colossal as the upper limit on its size advancement.

(The 52 ft shark was based on a largest tooth size of 6.61 inches. The largest megalodon tooth ever discovered seems to be around 7.62 inches, or 7 and 5/8 inches).

Of course, given that we're chucking out the basic rules for Spinosaurus (50 ft long, but quite a bit less than 32 ft long from nose to base of tail, and only 9 tons in weight) maybe we could have a general rule that macropredators can be smaller and lighter, within the same size category, than other creatures?

If a 32 ft Orca is Gargantuan, maybe, for really chunky, fish-shaped creatures, the rule is length to tip of tail?

Similarly, a 16 ft Orca would be Huge.

 

[Cleon]

Sharks caught in fishing contests, even big ones, do, I think, get weighed pretty accurately- possibly a winch built for the purpose?

That said, 4000 pounds (and anything from 17 to 21 ft long) is pretty reasonable for a Huge animal- it just gives it a rather short reach. Which could possibly be made up for, by removing either tail slap or bite (a whale shark wouldn't try and bite, a Great White wouldn't do tail slaps)

The figures usually given for the biggest whale shark caught (free-swimming specimens have been reported as rather bigger) was 41 ft long and estimated 15 tons. A good place to start Gargantuan at.

Quite, that fits in with my proposed rule-of-thumb of a 20 foot Huge shark, 40 foot Gargantuan shark, which assumes it's a fairly thick-bodied shark.

Speaking of thick bodied sharks, that reconstruction of megalodon as a 'monster shark' with an oversized head and jaws you linked to was quite interesting. I'm wondering whether the slimmer estimates I came across wandering around the 'net were based on the "Giant Sandtiger" model, since sandtiger-type lamniform sharks are more slender than great whites, as a rule.

One thing I have noticed about WoTC creatures- hit dices doesn't correspond all that well to weight. A 12 HD Gargantuan sperm whale-shaped creature, with a length given as 60 ft (Elsewhale, in Planar Handbook), seems decidedly low, given just how heavy a sperm whale actually is.

No disagreement there, they're all over the place. Although in the case of the Elsewhale at least it's consistent with the SRD sperm whale (the cachalot), which has the same HD and size.

I suspect that particular problem was caused by the 2nd edition AD&D monster manual's whale entry, which has common whales as Gargantuan creatures with 12-35 HD. If you read the small print it implies the 12 HD variety is a calf as little as 10 feet long, so presumably a "typical" 50-60 foot whale is more in the middle (24 HD?).

If I was to stat out a 52 ft long, 47 tonne Gargantuan megalodon, I'd give it rather more than MM2's 20 HD. It is one big beast.

You could start by using a SRD Dire Shark advanced to Gargantuan size - 33 HD and a 3d8+15 bite. That'd still leaves it with a measly 31 Strength.

And I might consider putting Colossal as the upper limit on its size advancement.

Sure, why not. If we can't have huge, ship-eating sharks in a fantasy game, I don't know what's the world coming to!

If a 32 ft Orca is Gargantuan, maybe, for really chunky, fish-shaped creatures, the rule is length to tip of tail?

Similarly, a 16 ft Orca would be Huge.

Yes, that'd work. Assuming a 20 foot orca is 3-3.5 tons and the 16 foot one has identical proportions it would weigh 3440-4014 lbs (long tons) or 3383-3946 (metric tonnes), which is pretty close to the Large/Huge boundary.

 

[hamishspence]

animal sizes

So,

Orcas can be 16 ft Huge, 32 ft Gargantuan,
Great Whites 14-15 ft Large, 18-20 ft Huge
Megalodons 52 ft Gargantuan, 75 ft Colossal
Sperm whales 35-60 ft Gargantuan, 70-80 ft Colossal?

These seem like good baselines.

(Though, for some reason, the Huge orca is described as 30 ft long in MM 3.5)

Come to think of it- instead of just going with "dire shark" to represent generic Huge and Gargantuan prehistoric sharks, we could pick out some of the more interesting ones. Dragon 318 had stats for Helicoprion, a shark with a whorl-like lower jaw. And there are possibily others.

Such as Cretoxyrhina, sometimes called "the Ginsu Shark", which was present in the late Cretaceous,, and was a bit larger than a Great White. Or Isurus hastalis, the broad-toothed mako, another big shark, believed to be ancestral to the Great White.

And even prehistoric Great Whites themselves, were rather bigger than any present day specimen- the largest present-day great White teeth appear to be around 2.75 inches long, whereas fossil Greath White teeth max out at 3.5 inches.