Image:header-trans
Image:header-trans

Dinosaurs Starving in the Early Jurassic

Early on I ran across a site listing Six "Flood" arguments that Creationists supposedly can't answer. One of the arguments that struck me as rather novel was the problem of too many animals. It used a rather fascinating quotation mentioning an estimate for the approximate number of fossilized animals in the Karoo Formation.

The evolutionist, Robert J. Schadewald, did a fascinating simple calculation using the estimate to determine a vast number of animals per acre that must have been living at the time of the Flood. So I thought why not try using the same estimate to work out the number of animals during, say, the Early Jurassic? If the evolutionists could use this quote, why couldn't we?

The Early Jurassic was chosen because during the course of the calculation I had found some dinosaurs larger than a cow in the Karoo Formation:

Karoo dinosaur
Ledumahadi
Early Jurassic: 200-195 Ma*
Weight: 12 tonnes
Length: 9 m

Image:Ledumahadi
* Million years ago.

And another:

Karoo dinosaur
Dracovenator
Early Jurassic: 201-199 Ma
Weight: 400 kg
Length: 7 m

Image:Dracovenator

Note: the approximate height for the dracovenator from the pic would be about 3.7 m. By these dimensions it would be about 5½ times the size of a cow. And if we allow the width to be double also, it could easily be 10 times the size of a cow!

This was in fact, extremely critical, because the evolutionists had been publishing for years that there were no animal fossils in the Karoo Formation larger than a cow. For years they had been lambasting Christians with Schadewald's number-of-animals calculation, and the document it contained had the simple statement:

"Robert E. Sloan, a paleontologist at the University of Minnesota, has studied the Karroo Formation. He told me that the animals fossilized there range from the size of a small lizard to the size of a cow, with the average animal perhaps the size of a fox."

Image:Cow
Image:Cow
Image:Cow

The approximate dimensions and weight for a dairy cow are 1.8 m high, 2.6 m long and 907 kg weight.

So as you can see from the dinosaurs I found above, this quotation is completely wrong on the size of the animals. Further many evolutionists and some universities have been supportive of this quotation by publishing it against Creationists.

Anyway this was a good start. So I began with the same estimate they used:

the Karroo Formation in Africa, which is estimated to contain the remains of 800 billion vertebrate animals

Schadewald's calculation was a bit dodgy, so mine could be too. I used the really rough approximation of 1 in a million for an estimate of living animals:

It is often stated in the paleontological literature that the chance an animal will become fossilized is "one in a million." This number is meant to be taken figuratively, the point being that the odds of surviving the rigors of deep time are extremely remote.
https://www.scientificamerican.com/article/what-are-the-odds-of-a-de/

This then gave approximately 8 x 1017 living animals for the Karoo region.

So we're going to need teams of paleontologists driving massive trucks through the Jurassic winter feeding bales of food to the hungry sauropods in their 270 acre grazing areas.

But there is no fixed point in time here as the fossils cover a period of 120M years:

The Karoo Supergroup is the most widespread stratigraphic unit in Africa south of the Kalahari Desert. The supergroup consists of a sequence of units, mostly of nonmarine origin, deposited between the Late Carboniferous and Early Jurassic, a period of about 120 million years.
https://en.wikipedia.org/wiki/Karoo_Supergroup

The simple solution to this dilemma would be to take a generational slice in time. Considering that some dinosaur lifetimes were quite long [Apatosaurus and Diplodocus dinosaurs up to 70 or 80 years] and really small animals very short lifetimes[1] I decided to use a rough approximation of 20 going on the T-Rex age of maturity:

These studies, done in conjunction with paleontologists at AMNH, document that that Tyrannosaurus, which attained a weight of more than 10,000 pounds as an adult, reached sexual maturity at about 20 years of age and lived for up to 28 years.
https://www.amnh.org/explore/videos/dinosaurs-and-fossils/how-fast-did-dinosaurs-grow-and-how-long-did-they-live

This gives 6M generations for the Karoo fossils and we obtain an approximate generational slice of

1.3 x 1011 animals for the Karoo region. Next it was a simple step to divide this by the approximate area of the Karoo:

Encompassing almost 500,000 square kilometres, the Karoo stretches across a vast swathe of South Africa and it mantles the Provinces of the Western Cape, Northern Cape, Eastern Cape and the south western sections of the Free State.
https://www.karoo-southafrica.com/

This translates to approximately 1.235 x 108 acres, and we finally obtain approximately 1000 animals per acre through the Karoo. And we could take this as a reasonable estimate for the whole habitable region of Pangea.

And we were thinking about our Ledumahadi and Dracovenator dinosaurs so we considered this slice as an approximate density of animals at some generation in the Early Jurassic.

Our dinosaur's grazing space?
Unfortunately our hungry dinosaur is going to be sharing this area with 1,482,999 other animals, many of which could be as large as itself!

So now we come to the question, will we have enough grazing area for our hungry Ledumahadi dinosaur? And it's a really good question to ask. Just how much grazing area would a hungry herbivorous dinosaur of this size need?

1000 animals per acre! Will we have enough grazing area for our hungry 9 m 12 tonne Ledumahadi dinosaur?

Image:Ledumahadi

We should be easily able to work out an estimate using the grazing area required for animals in the Karoo today.

The Karoo is a semi desert natural region of South Africa.
Today, sheep thrive on the xerophytes, though each sheep requires about 4 ha of grazing to sustain itself.
https://en.wikipedia.org/wiki/Karoo

Stop your car anywhere in the Karoo, away from the main highways, and you will immediately be assailed by the immense silence and peace of this extraordinary place. In the silence you may notice the movement of a herd of Springbok, the croak of a Korhaan or the ever present merino or dorper sheep with their distinctive black heads.
https://www.karoo-southafrica.com/

Dorper sheep weight:
74kg for males, 44kg for females.
http://agtr.ilri.cgiar.org/dorper

Merino Sheep
The Merino Sheep Ewes should weigh from 100 to 120 pounds (54.4 kg) and produce a fleece or 14 to 18 pounds (6.4 to 8.2 kg). The sheep rams average weight is from 160 to 180 pounds (72.6 to 81.6 kg) at maturity and produce fleece of upwards of 25 pounds (11.3 kg).
http://knowledgebase.lookseek.com/Merino-Sheep.html

So we will use 80 kg as a Karoo sheep approximation, requiring about 4 ha of grazing to sustain itself.

Using these estimates our 9 m 12 tonne Ledumahadi Early Jurassic Karoo dinosaur will require approximately 600 hectares of grazing, or approximately 1483 acres. Unfortunately our dinosaur is going to be sharing this area with approximately 1,482,999 other animals, many of which could be as large as itself!

And just what does this mean for our poor hungry dinosaur?
It means our 9 m 12 tonne Ledumahadi Early Jurassic Karoo dinosaur is going to STARVE!!


Postscript

What about the dino documentary where it gives 270 acres grazing area for a 50 ton dinosaur? [a large brontosaurus looking sauropod]

This translates approximately to 109 ha for a 45.4 tonne dinosaur.

This is way low from our estimate of 600 ha for our 12 tonne Ledumahadi Early Jurassic Karoo dinosaur.

So what's going on here?
Some interesting points. My guess was an estimate. They have used one too going from a 1000 lb cow to a 50 ton dinosaur. You're going to get a guess.

The cow was stated as needing 10 acres or approximately 4 hectares. 1000 lb is approximately 454 kg. From there a straight ratio gives approximately 400 ha grazing space required.

For our 12 tonne Ledumahadi dinosaur this would translate to approximately 106 ha grazing space. And if we use their estimate of 270 acres this would be lower still.

106 ha [or lower] or 600 ha it doesn't matter. Our hungry 9 m 12 tonne Ledumahadi Early Jurassic Karoo dinosaur will still starve.

So this estimate adjustment will make little difference to our study.

But there are two big problems with their estimate. And one they have made on the documentary.

"Jed was telling me, that a thousand pound cow if you were going to pasture it, about 10 acres..."

And that is very different to an animal in the wild, like our dinosaurs.

Back to the documentary...

1 cow needs about half a bale a day in the wintertime:
"You know, it takes about half a bale a day for a cow, is what we kind of figure in the wintertime."

That's pasturing the cow. So if we are going to accept their estimate of 270 acres for a 50 ton sauropod dinosaur then this dinosaur is being pastured.

So we're going to need teams of paleontologists driving massive trucks through the Jurassic winter feeding bales of food to the hungry sauropods in their 270 acre grazing areas.

That's one problem. The second one is more interesting. They state their 1000 lb cow only needs 10 acres. That's approximately a 454 kg cow and 4 hectares.

But our quote for the Karoo gave:

The Karoo is a semi desert natural region of South Africa.
Today, sheep thrive on the xerophytes, though each sheep requires about 4 ha of grazing to sustain itself.
https://en.wikipedia.org/wiki/Karoo


Using an approximate sheep weight of 80 kg that's a long way from a 454 kg cow and still only 4 hectares!

They can't both need 4 hectares to survive!

Of course the discrepancy is because one is being pastured and the other is not. And the geographical location [a semi desert region] also has an impact.

For a hungry sauropod in the Karoo their estimate is way low. My 600 ha estimate is probably safe, even if it may be a little off.

REFERENCES
1. just because I have written that any dinosaur had a life span.... does not necessarily mean that I believe this or that I believe that any of these dinosaurs actually existed.

Ledumahadi
Temporal range: Hettangian-Sinemurian, 200-195 Ma Ledumahadi (meaning "a giant thunderclap" in Sesotho language) is a genus of lessemsaurid sauropodomorph dinosaur from the Early Jurassic Elliot Formation in Free State Province, South Africa. The type and only species is L. mafube, known from a singular incomplete postcranial specimen. A quadruped, it was one of the first giant sauropodomorphs, reaching a weight of around 12 tonnes (26,000 lb), despite not having evolved columnar limbs like its later huge relatives.

At its time in the Early Jurassic epoch, Ledumahadi is thought to have been the largest land animal that had ever lived. It is estimated to have reached a maximum size of around 12 tonnes (26,000 lb) in weight;
https://en.wikipedia.org/wiki/Ledumahadi

The largest known dinosaur of its kind, Ledumahadi weighed over 13 tons (12 metric tons), and reconstructions estimate that it grew over 30 feet (9 meters) long!
https://carnegiemnh.org/mesozoic-monthly-ledumahadi/

Dracovenator
Temporal range: Early Jurassic, 201-199 Ma
Dracovenator is a genus of dilophosaurid theropod dinosaur that lived approximately 201 to 199 million years ago during the early part of the Jurassic Period in what is now South Africa. Dracovenator was a medium-sized, moderately-built, ground-dwelling, bipedal carnivore, that could grow up to an estimated 7 m (23.0 ft) long. Its type specimen was based on only a partial skull that was recovered.

Dracovenator is estimated to have measured between 5.5 and 6.5 meters (18 and 21 ft) in length. Others estimates suggest that Dracovenator was at most 7 m (23 ft) long and weighed 400 kilograms (882 pounds).

The type material BP/1/5243 for Dracovenator was discovered at the "Upper Drumbo Farm" locality in the upper Elliot Formation which is part of the Stormberg Group in Eastern Cape Province, South Africa.
https://en.wikipedia.org/wiki/Dracovenator

The Elliot Formation is a geological formation and forms part of the Stormberg Group, the uppermost geological group that comprises the greater Karoo Supergroup.
https://en.wikipedia.org/wiki/Elliot_Formation

Average cow dimensions:
https://www.dimensions.com/element/dairy-cows

Pics:

Cow
https://commons.wikimedia.org/wiki/File:201409_cow.svg
Author: DBCLS TV, Sebastian Wallroth
This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication
Public domain

https://commons.wikimedia.org/wiki/File:Ledumahadi_NT.jpg
Attribution: Nobu Tamura
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.

https://commons.wikimedia.org/wiki/File:Dracovenator_regenti.jpg
Attribution: Antonio Rares Mihaila
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.

Dino documentary

Dinosaurs Inside & Out
Series 1 Episode 2 Land of the Giants
New Dominion Pictures.
For discussions about pasturing a cow and dinosaur, see 7:30 & 9:20.


Top of page
Stephen Buckley
E-mail: starvingdinosaurs [at] mail.com
Last revised: 1 Feb 2022.
Construction started about 28 Oct 2020.


Page design/construction Stephen Buckley 2020.