If All the Dinos Died on One Terrible Weekend – Where are All the Bodies?

asteroid
Creative Commons License photo credit: goldenrectangle

According to the Impact Theory, a rock from space smashed into the earth, threw up a huge dust cloud, chilled the atmosphere and sent down acid rain.  All the dinosaurs died immediately all over the globe or in a week or so.

So….where are the bodies of the victims?

Probability of Becoming a Fossil: 0%     or    100%

0%
If you die on a high plateau or a grassy meadow or on the average forest floor, far from the influence of river floods, your bones will get chewed, cracked, smashed and digested by scavengers. The remnants will get dried up and will flake away to nothing under the sun. Or, if the ground is wet, worms and grubs and fungi will destroy your osseous remnants.

That happens to most dead bodies, most spots, most of the time. Or…

100%
What if you’re lucky enough to die in a depositional basin, where yearly floods bring in layers of sand, silt and mud, and where lake bottoms accumulate blankets of sediment all the time. A place where huge sand bars develop in streams and rivers….

….then the possibility that some of your bones will get buried and fossilized rises to close to 100%.

Dino Extinction Supposedly Hit While Montana Was Getting Sediment
At the time of the Great Dino Die-Off, no sediment was being laid down in most places in the world. But in Montana’s Cretaceous coal fields, there were many swampy lakes and sluggish rivers, locales where mud and sand was being carried in. This depositional activity seems to have continued right through the end of the Cretaceous and beginning of the next Period, the Tertiary (“Age of Mammals”).

In fact, field geologists have a hard time telling where the Cretaceous mud ends and rhe Tertiary mud begins.

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Creative Commons License photo credit: etee

If the Impact Theory is right, millions of Triceratops carcasses littered the landscape. Tens of millions of duck-bill dino bones also covered the ground. And….there were no big scavengers to crack the bones. The average dino body would last far longer than usual. Some of the impact victims should have had a high probability of being buried in the mud at the Impact Layer, the sand and silt and mud deposited right after the rock from the sky struck.

Total number of dino bones found right at the Impact Layer – 00.00.

That’s  one reason why I am an Impact Skeptic. You have to do some special pleading to explain the lack of dino bones at the impact layer. You could argue that soil acid dissolved the bones. Or that for a hundred years there was no new mud, no new sand, no new silt.

Could be.

Still, I like to begin with a geological peshat (first impression): When I scan the actual facts on the ground, there is no evidence whatever of a sudden massive death of dinosaurian multitudes at the Impact Layer.

I dinosauri a Cremona
Creative Commons License photo credit: Simone Ramella

Evidence for a Long, Slow Disaster
There are clues that indicate the dino ecosystem was deteriorating long before the impact. The diversity among big, multi-ton dinos went way down about 5 to 10 million years before the end. In the Latest Cretaceous (Lancian Age) in most places in Montana, there are only two common big dinos – either Triceratops or the duckbill Edmontosaurus. It was a dino-monoculture.  At 76 million years ago diversity was much higher.

Serial Killer in Deep Time
The biggest reason I’m a skeptic is the victim profile. When the dinos finally went extinct, salamanders, frogs, pond turtles, river gators all survived and thrived. So did most small terrestrial species. That pattern holds for six other mass extinctions – beginning at 285 million ears ago, long before the first dino. And the pattern is obvious in the last extinction at the end of the Ice Age, 11,000 years ago.

Impact Theory Fails to Predict the Correct Victim Profile
Sudden chill and acid rain will wipe out salamander-oids and frog-oids and turtle-oids. And hit big, active animals far less severely.

The wrong animals died.

Read about my dinosaur extinction theory in an early blog post.

Dino Derby: What was T. rex’ top speed?

How Fast was the T-rex?

Tyrannosaurus Rexstirs passions.  Adults get scared when they imagine a live T-rex chasing kids in a theme park. And kids get a thrill when they day-dream of having a T-rex as a pet.

We scientists get passionate too, we sometimes get so excited we yell at each other when we debate a  T-rex’s speed and hunting habits.

One PhD will start with: “T-rex was a slow-footed fumble-bum! And he didn’t kill anything – he just ate carcasses he found already dead!!”

Then a bunch of us will reply: “That’s just nuts!  Tyrannosaurus was faster than any big veggie-saur! And one bite could kill a duck-bill!”

Who’s right?

TOOLS & RULES.

We need tools – mathematical rules to tell us how fast an extinct animal could run and whether a meat-eater could catch his prey.

Lets take the CHEETAH versus LION.

First we need two critters, close relatives, who have very different top speeds. Lions and cheetahs are perfect. They’re both big cats and they have the same basic design in leg joints.

Cheetahs are way faster. Cheetahs hit nearly 70 mph in a sprint. Lions can’t go much faster than 40 mph.

LONG ANKLES.  Check out these two diagrams. Ok – where does the cheetah get its extra velocity?  From its ankles. Much of the high speed comes from longer ankle bones. The ankle length compared to the thigh length is a reliable speed index in close relatives.

That’s an old Rule that Darwin knew back in 1859.

T-REX versus DUCK-BILL

Duck-bills were the most common big veggie-saurs in the time of the T-rex. The question is, could a T-rex catch a duck-bill?

We need to measure ankles compared to thighs in a rex and a duck-bill of the same geological time zone. Duck-bills and T-rexes have basically the same style of hind legs. And the hind legs deliver all or almost all of their  forward thrust (Duck-bills did put their finger tips down on the ground while walking – but there wasn’t much weight on the forelimb.)

Check out diagram # 3. Here’s a T-rex with a thigh (femur) that’s 1200 mm long. And next to the T-rex is an Edmontosaurus, a big duck-bill.

Who has longer ankles?

THE T-REX!

The longest bones in the ankle are the metatarsals. And the rex has much longer metatarsals, compared to the duck-bill.

CONCLUSION:
T-REX COULD CATCH A DUCK-BILL EASILY, IN A SPRINT ON OPEN GROUND.

That’s cool.  But now we have more questions – how fast was a duck-bill and a T-rex, in mph?  And did a T-rex have the killing equipment necessary for bringing down live prey? Stay tuned for the answers to these questions.