Prehistoric Predators : The Biggest Carnivores Of The Prehistoric World by Brian Switek

Explore the fascinating world of Prehistoric Predators and uncover the most formidable carnivores that ever roamed the Earth. This thrilling journey takes you face-to-face with the largest and deadliest creatures in history. From the iconic T-Rex and Giganotosaurus to the fearsome Spinosaurus and monstrous Megalodon, get ready to witness these terrifying predators like never before.

Renowned paleoartist Julius Csotonyi brings the ancient world to life with his breathtaking illustrations. Each page is a vivid depiction of these dangerous creatures, capturing their power and ferocity. With the turn of every page, you’ll be transported back in time and immersed in a world dominated by these awe-inspiring predators.

Written by National Geographic contributor Brian Switek, Prehistoric Predators is more than just a visual feast. It is a trove of captivating facts that shed light on the behavior, anatomy, and incredible adaptations of these prehistoric carnivores. You’ll learn about their hunting strategies, size comparisons, and the unique features that made them so successful in their ancient environments.

But it’s not just the content that makes this book a standout. The cover itself is a work of art, designed to replicate dinosaur skin. As you hold this book in your hands, you can feel the texture of the prehistoric world, adding a sensory element to your reading experience.

Prehistoric Predators is a must-have for dinosaur enthusiasts of all ages. Whether you’re a seasoned paleontology fanatic or just starting your journey into the world of ancient creatures, this book will captivate and educate. So, get ready to embark on a thrilling adventure and come face-to-face with the most dangerous carnivores that ruled the Earth!

The Age of Giant Insects: How Oxygen Shaped Earth’s Prehistoric Arthropods

This episode is supported by the Greek courses plus. Even though we often refer to this time in history as the age of mammals, we should probably be calling it the age of insects because, just looking at the numbers, there are way more of them than there are of us humans. Alone, we number more than seven billion at this point, which is a lot. But insects? Try 10 quintillion. We may like to think we’re in charge because we make the rules, and, well, we’re bigger than they are. But insects and other arthropods weren’t always so small. About 315 million years ago, they were not only abundant, they were enormous. To meet the biggest invertebrates to ever crawl across the earth, we have to go back to the Carboniferous period from 298 million to 358 million years ago. That’s when you’d find the likes of Meganeura. It was a griffinfly, a giant relative of today’s dragonflies, that had a wingspan of about 70 centimeters. That’s about the size of a pigeon, more than three times larger than the biggest living dragonfly. Metre by comparison, was Meganeuropsis, another griffinfly that was still some 40 centimeters across, about as big as a robin.

And this greatness in size wasn’t limited to insects. You see, outside arthropods all over the world during this period- like Arthropleura. You know those cute little millipedes you find curled up under rotting logs in the woods? Now imagine one of those about two meters long and a half a meter wide, shuffling like a living carpet over the undergrowth. It was probably the largest arthropod that ever walked on land.

So, what allowed these invertebrates to get so big? The answer is oxygen. Take a deep breath. Right now, the amount of oxygen in the atmosphere is about 21%. But back in the Carboniferous, it was nearly 35%. That’s because the Carboniferous was a time of incredible runaway plant growth. Huge forests full of ferns, mosses, and some of the earliest vascular plants had taken over much of the planet. They sucked in the carbon dioxide and pumped out oxygen in enormous amounts.

You might be thinking, “Earth has a lot of trees now, so what’s the difference?” Well, today, that big log you find in the woods with all those bugs underneath it? That log is being decomposed by bacteria, among other things, that take in oxygen and release CO2. But in the Carboniferous, those wood-eating bacteria didn’t exist yet. So, Earth’s giant primordial forests were taking in lots of carbon dioxide and pumping out lots of oxygen. That’s what plants do. But since the trees weren’t decomposing, the CO2 wasn’t being released back into the atmosphere. The result was an all-time high in the world’s levels of atmospheric oxygen. And that’s what made giant arthropods possible.

So what allowed these invertebrates to get so big? **The answer is oxygen**. Take a deep breath…Right now, the amount of oxygen in the atmosphere is about 21%. But back in the Carboniferous, it was nearly 35%. That’s because the Carboniferous was a time of incredible runaway plant growth…huge forests full of ferns, mosses and some of the earliest vascular plants had taken over much of the planet. They sucked in the carbon dioxide and pumped out oxygen in enormous amounts. You might be thinking – Earth has a lot of trees now, so what’s the difference? Well, today that big log you find in the woods with all those bugs underneath it — that log is being decomposed by bacteria, among other things, that take in oxygen and release CO2. But in the Carboniferous, those wood-eating bacteria didn’t exist yet. So, Earth’s giant primordial forests were taking in lots of carbon dioxide and pumping out lots of oxygen. That’s what plants do. But since the trees weren’t decomposing, the CO2 wasn’t being released back into the atmosphere. The result was an all-time high in the world’s levels of atmospheric oxygen. And that’s what made giant arthropods possible…Because arthropods don’t breathe the way we do…they have a system of external openings called spiracles that lead to a branching network of tubes called trachea that diffuse oxygen through their bodies, and this puts a limit on their body size. Arthropods can only get so big before they can no longer draw enough oxygen from the air. But in the Carboniferous, the abundance of oxygen in the atmosphere made it easier for arthropods to get the O2 they needed, which allowed them to reach record-breaking sizes. In fact, paleontologists have managed to make this happen today in the lab by experimenting with modern insects. By raising dragonflies, beetles, and other insects in controlled oxygen-rich enclosures, scientists at Arizona State found that successive generations of arthropods can grow faster and larger.

But of course, it’s possible to get too much of a good thing. So, some scientists have proposed another theory that arthropods got huge not because they could, but because they had to. Lots of oxygen might have been beneficial for grown-up arthropods, but it also could have posed a threat to their larvae. Young invertebrates can’t control their intake of air like adults can, and too much oxygen can be deadly. So, researchers at Michigan State have suggested that ancient arthropods began producing bigger larvae so they take in less oxygen relative to their body size, and those bigger larvae resulted in bigger adults.

But you know enough about natural history at this point to know that even the biggest creatures don’t stay on top forever. About 275 million years ago, during the Permian period, the world changed yet again. The levels of atmospheric oxygen started to plummet. Why, we’re not sure. Ancient climate shifts might have had something to do with it. But as oxygen levels fell, the interiors of the world’s continents got warmer. The big swamps that acted as natural carbon sinks shrunk. Swamps weren’t pumping out as much oxygen as they used to. And on top of that, decomposers finally appeared and were able to start breaking down all of the dead wood. As these microbes took in oxygen and released carbon dioxide, global levels of O2 dropped even more. And with less oxygen available, it became increasingly hard for the giant arthropods to survive. By about 305 million years ago, the two-meter-long Arthropleura could no longer be found on the forest floor. By 299 million years ago, the last of the Meganeura had flapped its wings. The arthropods that followed never got quite as spine-tinglingly large as their ancestors were.

But of course, everything turned out fine for them. Today, we’re totally outnumbered, both in biomass and in diversity, by insects, arachnids, and other land-based arthropods. But if there ever was a time that was a true age of insects, it was probably the Carboniferous period when arthropods of all kinds were living large.