Among fossils: How very old things remind us of our youth

The earth is 4.54 billion years old. That’s a big number to wrap your head around. Spending time among very old things helps, but even then it’s easy to forget that not only the fossils themselves are ancient; so is the rock they came out of, the planet circling a sun that has been around a long time.

Since my childhood, dinosaurs have arrested my imagination like nothing else in science, and what better place to witness the majesty of these ancient animals than the Houston Museum of Natural Science, displaying some of the oldest things on Earth? When I walk through the Morian Hall of Paleontology, I see the bones of creatures that lived millions of years ago, preserved naturally by the processes of geology, like mummies, but embalmed by mud, pressure, and minerals. These aren’t bones, really. They’re rocks, no different from petrified wood or the crystals in the Cullen Hall of Gems and Minerals. They were once creatures of flesh and bone, but the organic molecules and chemicals that made up their bodies, if they didn’t decay, were replaced atom by atom while the rest of life on Earth developed.


Lane, the most complete fossil specimen of Triceratops in the world. 65 million years old.

Mine is a problem of scope, I think. It’s a strange feeling to understand that Lane the Triceratops, the most complete specimen of this dinosaur, was under our feet during the fall of the Roman Empire, was still buried in the time of King Tutanhkamen, and remained undiscovered while Shakespeare wrote his sonnets. This animal died, and life went on as it always does. Its life among presumably millions of others like it was common. Undistinguished. But that specimen is no longer a Triceratops; it’s a skeleton made of rock. Not even a skeleton, but an impression of it. A three-dimensional photograph dug out of the album that is the many-layered dirt of our planet. This animal has become a symbol of history. Now that is rare.


Icthyosaurus mother. At least 146 million years old.

It’s remarkable, this action of preservation that the Earth is capable of. And it’s remarkable that we have developed the science to identify and understand these stones. We had to consider both the life cycle of rock and the taxonomy of life before we could begin to speculate what these samples could mean. But really, so what? They’re just rocks.

It’s the feeling of humility they deliver that makes them fascinating. It’s like walking through modern Rome after living in developing Houston, surrounded by buildings a thousand years old that stood before the United States was even imagined. We’ve been walking around these seven continents for millenia, in the dark about what was under our feet until the birth of paleontology in 1666, when Nicholas Steno identified “tongue stones,” known then only as triangular rocks, as fossilized shark teeth. Dinosaurs were around whether we knew they existed or not. They are as old as the rock we walk on.

Icthyosaur Baby

Impressions of Icthyosaurus pups in the rib cage of this rare specimen suggest this animal died in childbirth.

Now consider this. In 2011, biologists identified 20,000 new species, a large number of them beetles, and most of them invertabrates. That was in a single year. Now take that diversity and multiply it by the age of the Earth. I’m not going to do the math, but that’s the number of species paleontologists have yet to discover. That’s the amount of life we potentially have yet to search for in the rock.

After early hominids, fossils of the first humans date back 1.8 million years, along with mammoths, mastodons, and saber-toothed cats that appear in the rock alongside them. Triceratops lived in the late Cretaceous, discovered in rock at least 65 million years old. Icthyosaurus swam the oceans and gave birth to her young between 245 and 146 million years ago, in the Jurassic and the Triassic. (Their era lasted 100 million years. Again, we’ve been around for 1.8.) Trilobites in our collection have been preserved for between 540 and 360 million years, and the stromatolites, layered rocks formed by ancient bacteria, date back to 3.4 billion years. Not million. Billion. They appeared in the Archaeozoic Eon, about a billion years after Earth solidified out of molten space-rock.


One of the best preserved and most intricate trilobites in the world. At least 360 million years old.

What will the occupants of this planet find after the next million years? We’ve been around for a while, but not nearly as long as these fossils. What will paleontologists of the future, if they still exist, find in another 65 million years? 146? 540? 3.4 billion? The Earth will still be here by then; humanity is another story. Will we still cling to the crags in a different form, the maps unrecognizeable to the once-dominant species of 2015 CE, if they could see them? Will we have preserved our history as well as the rocks have preserved the dinosaurs?


Stromatolite formed by layers of ancient bacteria preserved in rock. At least 3.4 billion years old.

In another 3.4 billion years, the sun will be nearing the end of its life, having expanded into a red giant and swallowed Mercury and Venus. According to many estimations, by the time the sun is 7.59 billion years old, it will engulf the Earth. We are living in our planet’s middle age. It took half the Earth’s life for humanity to arise and build its cities. For the United States to claim its sovereignty.


Lucy, Australopithecus afarensis, the most complete skeleton of this hominid in the world. 3.18 million years old.

The Earth is old, dude! We never pay this age any mind until we identify something to date it against. Here we have Triceratops, say, a creature that lived in the time when this rock was young, just a pile of sediment on the floor of the ocean or a river. Paleontologists owe a lot to the power of speculation and theory. We may never know for sure what life was like in the era of these ancient creatures. But if we have anything in common with the dinosaurs, ancient mollusks and archaebacteria, it’s that we all grew on this same rock.

In a way, we’re just as old as they are. Our bodies are made up of the same elements that have always been here in some form or another, buried under the crust in a molten mantle, or exposed to the light of the sun that has fueled life on Earth for as far back as the imagination will stretch. As Carl Sagan said, “We are all made of star stuff.”

Lucy’s Great Mystery: Part 3

In Part One we learned the frightening facts: Lucy was surrounded by formidable felines. She was too slow to run away and she didn’t have weapons to repel 150 pound leopards or 500 pound  homothere saber-tooths.

In Part Two we discussed even more of the fearsome predators surrounding Lucy, and began to discuss how futile fighting back would be.

How Could Our Lucy Survive a Legion of Cats and Hyenas?

How did she defend herself?

Here are some suggestions:

She made sharp-edged knives out of broken antelope bones and buffalo horns
Lucy model - faceThis was a popular theory in the 1950’s.  In South African caves, Lucy’s relatives are found with hundreds of broken antelope bones, horse bones, and broken horns form all sorts of hoofed creatures. Conclusion: Australopithecus didn’t make stone tools – they made bone-tools.

Supposedly Lucy and her clan smashed antelope legs and used the sharp-edged ends the way a hockey fan would use a broken beer bottle in a bar-fight. “Poke, whack, stab!”

Broken bones can be nasty weapons, it’s true, but….

Hyenas broke the bones
Careful analysis of the way the bones were broken proved that Australopithecus didn’t do the breaking. Teeth marks on the bones and the style of breakage matched what we see today around a hyena lair. All of those cave bones had been smashed by the big teeth of hyenas and maybe big lion-sized cats. The predators smashed Australopithecus bones too.

Maybe – Lucy Smelled Bad – Or Tasted Bad

Striped Skunk
Creative Commons License photo credit: Charles & Clint

Seriously – this is a theory we must consider. A few animals stink so thoroughly that predators won’t attack. Skunks are a good example. Even mountain lions are repelled by one spray from the stink glands of a Texas skunk.

And meat can stink or be poisonous. Toxins in the Fugu fish are deadly – if you go to a restaurant and gulp down the wrong part of your Fugu, you’ll die. So…..maybe Darwinian processes gave Lucy toxic flesh.

But primates don’t evolve super-stink
Today we just don’t find any lemurs, bushbabies, monkeys or apes with toxic meat or stinky glands.  In fact, most stinky mammals are predators – skunks, ferrets, and stink-badgers. So, although it’s theoretically possible, we should not be too enthusiastic about Lucy evolving chemical defenses.

Let’s Review Lucy’s Potential

ChimpUs-frontSkeletonLabelLet’s review what Lucy could do – we have nearly all the bones from the skeleton if we supplement Lucy and other Ethiopian finds with close relatives dug from South Africa. Follow along by scrutinizing our Lucy-chimp-us body diagram.

No Grabber Toe
Lucy’s big toe was like ours – it didn’t face away from the other toes the way a chimp big toe does. So Lucy couldn’t grab a branch and climb like a chimp.

Knees Together
Chimps can’t stand perfectly upright, because their knees slant down and out. But Lucy could stand in a modern posture – her joints were shaped so the right and left thighs came down and towards each other. She’d walk and run like us modern humans too – knees close together.

Strong Shins & Thighs
Lucy did have muscular, short shins and thighs. No, she couldn’t sprint as fast as a modern human but she could accelerate fast and turn quickly. And short legs actually are good for climbing.

Modern Hips
Lucy had wide upper hips, like ours, not narrow hips like a chimp’s. Wide hips are good for supporting guts when standing and running upright. And….wide hips could be good for climbing straight up a tree, if arms and legs work together. We see modern people shimmying up coconut palms this way.

Lucy – NOT America’s Next Top Model – Compact Torso
Today’s humans have long waists – especially in the Hollywood starlets and runway models. Not our Lucy. As the song goes, Lucy had “..strong thighs and shins… and her torso…even more so.” Lucy had no waist. Her barrel chest was set on top of her wide hips.

That gave her a low center of gravity, a design useful for three-dimensional movement. Lucy was a natural gymnast! She could jump and twist and do somersaults.

Shoulder-Socket Half Chimp
Lucy’s shoulder socket was half-chimp, half human. The joint let her raise her arms further up, above her head, than we can – but not as far as a chimp. Raising your arms high is useful for climbing vertically; hand over hand (the way we were taught in gym class in seventh grade).

Long Arms
Lucy is half-chimp in arm proportions too – her whole arm is longer and stronger compared to her legs than what we see among modern people. And strong arms certainly would assist in climbing.

Curved Fingers
So far, our review of Lucy’s anatomical equipment is a surprise – she’d walk like a modern human on the ground, but she might be able to climb vertically much better than we can. However – if she really was supposed to climb, she’d need long, curved fingers to wrap around branches.

Did she? Were Lucy’s fingers more curved than ours?


Australopithecus did have more curve in the digits. Not as much as in a chimps but still more than in modern humans.

So, after reviewing all of Lucy’s potential, we now can give her advice:

LUCY!  To avoid being eaten…..STAY NEAR A TREE!

She wouldn’t have to climb like a chimp, but she would have to be near enough to a tree so she could shimmy up when the cheetah charged or the hyena pack came galumphing over a hill. She wouldn’t have to scoot over a branch, holding on with her big toe, chimp-style. But she could avoid most meat-eaters by going vertical.

The Old Theory Is WRONG! Lucy Did Not Evolve on the Open Plains.

Back to our original problem: the old theory said Lucy and her kind evolved to move over open, tree-less terrain. We now have new evidence – from fossil herbivores – that the theory is incorrect. If Lucy lived in treeless areas, her bones should be found only with hoofed animals adapted to plains– the wildebeests and gnu, for example. And zebras. We shouldn’t find woodland herbivores like black rhinos and mastodons.

In fact, the antelope and rhinos and hippos and mastodons we dig with Lucy are mostly woodland critters, adapted to move over grassy areas with many bushes and clumps of trees nearby.

Mystery Solved! Lucy Evolved to Stay Near an Escape Tree.

Her family could forage on the ground. And climb up and away. And maybe they did use pointed sticks to jab down at any leopard who tried to follow.

Our ancestor, Lucy, was a success because she made her world three-dimensional.

Lucy’s Great Mystery: Part 2

Big Cats Everywhere:
Fast Cats,  Semi-Saber Cats, Super-Fast Cats. Not to Mention the Super-Hyenas!

In Part One we learned the frightening facts: Lucy was surrounded by formidable felines. She was too slow to run away and she didn’t have weapons to repel 150 pound leopards or 500 pound  homothere saber-tooths.

Actually – we left some facts out. The predator situation was even worse then what we discussed in the last article.  Lucy’s world had even more kinds of meat-eaters to fear:

These speedsters have greyhound-like limbs, very long and tipped with nails, not claws. Cheetahs sacrifice climbing ability for acceleration and velocity on the ground. Living cheetahs are leopard size – 120 lbs average. But in Lucy’s time cheetahs were as big as modern lions.

Semi-Saber Tooths – Dinofelis
These felids had the slinky bodies of leopards with an enlarged upper fang. Their saber teeth weren’t as long or as sharp as a Sword Tooth cat but were far larger than in any modern cat.

Sword-Tooth Saber Cats – Smilodonts
These are the chunkiest, most heavily muscled saber-tooths.  In Lucy’s time, smilodonts grew to jaguar size, were heavier than a leopard, but had even more massive forearms and paws. Climbing would be excellent but speed on the ground was slower than a lion’s.  The upper fangs were much longer than those in a Dagger-Tooth homothere.

Lucy would have had to deal with Hyenas too……

The feline situation looked bad enough. The hyenas made it much, much worse.

s-cats-hyenColorRSmallLucy’s time saw the maximum diversity among the African  Hyena clan. Today, the most advanced pack hunter is none other than the Spotted Hyena, Crocuta crocuta. This is a matriarchal hunter. The biggest males don’t rule. Mom does. The alpha female is bigger, smarter and scarier than the males and she makes most of the decisions. Her sisters are next in charge. The Spotted Hyena has a close-knit social structure, and the dominant females are needed to keep order. It works to the kids’ advantage. If  Mom-Hyenas dies, her sisters will help raise the orphans. Hyena clans fan out and go after zebra and antelope, even water-buffalo and young rhinos. The Hyenas run and run and run. They’ve got great stamina.

Super-Crusher Hyena
Lucy had to watch out for Pachycrocuta, what I like to call the Super-Crusher-Hyena. This monster was a close kin of today’s Spotted Hyena but weighed almost as much as a lion – 300 pounds. And the Super-Crusher had jaws with even greater bone-smashing power than in the Spotted Hyena.

A clan of Super-Crusher-Hyenas would have instilled fear even in the biggest Saber-Tooth Cat.

In Lucy’s time there was a Hyena menace we don’t have today. It was Chasmaporthetes, the Wolf-Hyena. A Wolf-Hyena, seen from a hundred yards away, would look like big-headed Timber Wolf – long-legged, fast, and graceful. Up close, you’d see the Hyena family design. The paws were more compact than a wolf’s and the jaws had meat-cutting teeth were longer and sharper. And there weren’t any big molars in the rear of the mouth. Wolves and coyotes use those rear molars to crunch berries and fruit and other vegetable food. The Wolf-Hyena was more of a pure carnivore.

The Wolf-Hyenas must have been the nightmare of mid-sized hoofed stock, and primates of all sizes, including our Lucy.

Can’t Bite Back.   What defenses Did Lucy Have?

Creative Commons License photo credit: rdicker

Chimps and baboons can bite back. They have big canine teeth, especially large in the males. A 90 pound baboon or ape is a nasty close-in fighter. Leopards and hyenas can get terrible wounds from ape and monkey teeth.

But not Lucy.  When australopithecines evolved from apes, the canine teeth got small. Lucy had much poorer dental weapons than what her ape ancestors had.

Final Conclusion:

Let’s roll-play again…..,you’re Lucy or her mate. You weigh 60 to 90 pounds. What do you do when a pack of Wolf Hyenas come over the hill? You can’t out-run them. You might be able to fight off just one Wolf-Hyena, but not a pack of a dozen.

Let’s say by some miracle you get away from the Wolf Hyena clan – then a Giant Cheetah comes at you at 55 mph.

Or you’re resting and a Semi-Saber Tooth Cat attacks. Or a smilodont?

You haven’t a chance….

Old Theories Are Missing Something.

BUT….Lucy and her family did get away, again and again and again. They lived long enough to mate and raise kids and evolve.

How did they do it?

What do you think?

Lucy’s Great Mystery: How Could Australopithecus Survive and Evolve Into Us?

Part One:

She Should Have Been Caught and E A T E N !

Lucy evolved into us. Really, really (to quote “Shrek.”)

Her species, Australopithecus afarensis, or something extremely close, changed over three million years to become Homo sapiens – the species that includes you and me.

So we should treat Lucy with respect…….

….but wait.  There’s a problem. It shouldn’t have happened. Lucy and her whole species should have been gobbled up by a legion of voracious, bloodthirsty carnivores! She shouldn’t have had any time to evolve at all.

Darwin Makes Sense (usually)

Evolution should be logical – when we have enough data. Textbooks used to say that Lucy evolved from an ancestor who was built like a chimp. But Lucy’s knee and ankle and hip bones were NOT chimp-shaped. The design of Lucy’s joints is very close to what we have – so we know that Lucy walked upright, on just her hind legs, with left and right knees close together.

s-Parade-Blog-ColorFine.  Did leg evolution make Lucy better?  Faster? That’s what we’d expect. But it looks like evolution made Lucy  s l o w e r !  Chimps run very fast and can change direction in an instant. These apes zip around on all fours, running on their knuckles. A modern human has great difficulty catching a running chimp – I know, I used to be a zoo-keeper in charge of three boisterous chimps.

Lucy couldn’t match chimps in speed and maneuverability. Since she walked just on her hind legs, her arms were useless dead weight in running. Plus – she was very short in the legs. Her shins and thighs were far shorter than in modern humans. She was not nearly as fast as we are today.

Why would evolution make Lucy slower?

Lucy – Evolved for Holding Babies on the Open Plains?

The standard theory said that Lucy’s upright posture was fit for moving across savannah, open grassland with scattered trees. She could walk for hours and use her hands to hold her babies or an armful of fruit or a big Pliocene salad or whatever.  Meanwhile, her chimp ancestors stayed in the forest. Sounds good……except we have a huge problem. The savannahs were occupied by a whole host of predators  who would love to eat Lucy and her kind.

In fact, Lucy was evolving during the worst possible time. The australopithecine clan evolved between 5.8 to 1.8 million years ago. This interval produced the scariest variety of big feline meat-eaters the world has ever seen.  Here’s what was out there, ready to catch Lucy and her kin.

s-Kitties-Blog-ColorLLeopards are stealth felines who lived with Lucy. They had short, wide paws, flexible legs and body. That’s a build excellent for climbing rocks, hiding in burrows, ascending trees – and sudden ambush! Body weights went from 50 lbs to 200 lbs.

Lions & Tigers
Lucy’s neighbors included lion-like cats, huge predators up to 500 lbs, with massive paws that could swat down a water buffalo. Legs were longer, straighter than a leopard’s and speed over level ground was higher. Because of the great weight, climbing was less agile than a leopard’s.

Dagger-Tooth Saber Cats – Homotheres
Lucy’s world was jam packed with saber-toothed cats. The biggest were the Dagger-Tooths, who were built like a cross between a cheetah and a leopard, with long legs, excellent for fast running with some climbing. Sizes ranged from up to 500 lbs. The jaws were like a rattlesnake’s. They opened so wide that the upper fangs were exposed and ready for action. The upper fangs were long, wide blades with very sharp, saw-toothed edges. Homotheres slashed and stabbed so deeply they could kill an elephant.

Long, muscular necks let saber-cats swing their head down like a battle-ax.

How could Lucy avoid these deadly cats?

Imagine that you are Lucy. You’re waking along the savannah, carrying a load of  melons. Then, without warning…..WHAM!  A leopard leaps on you, bites your neck, and you are leopard-kibbles. Or….you’re resting on a rock when…..WHAM!  A pride of lions jump you and tears you apart. Or….you’re plucking figs from a fig tree when…a Dagger-Tooth jumps up from the tall grass. You try to run as fast as you can….but in ten seconds…WHAM! Zip-Zap!  The cat slices you into bite-sized pieces.

Lucy Defended Herself With Spears?

An old theory says that Lucy’s kind used spears and rocks for defense. But that notion doesn’t work. We find no stone tools at all with Lucy’s bones, not a spear point or a stone knife.  How about a wooden spear? Chimps today make mini-spears from twigs and impale bugs and little furballs. Sure, Lucy might have picked up a branch and chewed the end to make a point.

But if Lucy poked a  Dagger-Tooth in the butt with her spear, she’d only make him mad.

No, wooden spears aren’t enough to drive away lions and leopard and saber-toothed cats.

Conclusion: Lucy and All Her Kind Should Have Been Massacred by The Big Cats.

We’re left with a big problem. How did Lucy get away?

Please! Help our Lucy!!!!!

Send in your suggestions about how to avoid predators!

Interested in learning more about Lucy? Check out my previous blog posts on Australopithecus afarensis migration.