Pterosaur

The first non-insect animals to evolve powered flight, these absolutely terrifying winged reptiles could be found in all three periods of the Mesozoic era, lasting roughly between 228 - 66 million years ago. Pterosaurs were carnivores that came in all sizes, the largest of which is shown below:

Scared now.

 With one group of Pterosaur having 4-inch long needle-like teeth, and a wingspan of over 10 meters, these reptiles used their arms to polevault themselves into the air, and they were the #1 divas in the sky during the dinosaur era. A misconception is that the pterosaur was a dinosaur, but the reality is that dinosaurs and pterosaurs were cousins who shared an ancestor, the Archosaurs. The evolutionary split on the archosaurs timeline sees one branch evolving into dinosaurs, pterosaurs and later birds, and another branch evolving into crocodiles. And it's because of this that we can say crocodiles and alligators are the closest living relatives to birds today! Recent family portrait:

Gigantopithecus

 Setting the dial on our geological time travelling machine to a relatively recent period now, as we head back only 150,000 years ago to the Pleistocene epoch. In the dwindling bamboo forests of South Asia we might find our extinct homo-genus cousins, Homo Erectus (the oldest living of the homo- species) treading very carefully. That's because Homo Erectus had to share these forests with Giganthopithecus Blacki, the largest ape ever known. At nearly 10 feet tall, these bamboo-eating apes were King Kong before King Kong was even a thing.

My interest in Giganthopithecus was fuelled when I saw an artistic interpretation of what one of these apes might have looked like, and I was struck by the immediate resemblance to my ex-partner. Regardless, much of what we know about this 540 kg 'bigfoot' comes from teeth and jaws found in Vietnam, and the dental studies show that they lived on a diet of seeds, fruit and bamboo. What led to their extinction is likely to be a combination of climate change and a low reproductive rate, although there is also a strong possibility that Homo Erectus aggravated their demise, as shown in this aforementioned illustration:

Meganeura/Arthropleura

The Carboniferous period (358-298 million years ago) is one of my favourite periods of geological history, simply because my imagination runs wild with what it would be like to get to spend 24 hours in a world with giant amphibians as the dominant land animal and king-sized versions of insects we know today buzzing around -
                          

    Presuming somebody found a way to fulfill my dream send me back 300 million years for a day jolly, I'd actually only have to last 22.4 hours in a Carboniferous forest, as the Earth's rotation was faster back then. There'd also be the added problem of ensuring that I didn't immediately die from change in atmosphere as the oxygen level was much higher. The high oxygen level in the carboniferous forests (35% compared to 21% today) meant that insects such as dragonflies, cockroaches and millipedes grew much larger than their ancestral equivalents we know today. For example:

The Meganeura is one of the largest insects of all time, with a wingspan of nearly 26 inches (remind me to insert a picture of myself holding two 12-inch rules side by side here later for dramatic scientific effect)

Of course, should I manage to bat away the Meganeura and not wet myself in bug horror, I'd need to keep an eye on the forest floor too, in case I trip over an Arthropleura, the largest arthropod of all time. Scientists estimate that these arthropods could reach sizes of 6 foot 6 inches:

Here's a great clip from David Attenborough's "First Life" which shows an Arthopleura in action:

....A dramatic change in climate marked the end of the Carboniferous period and the reign of these TERROR INSECTS (as I'm now nicknaming them) came to an end. The following Permian period started with an ice age, and the continents all locked together to form PANGEA, one giant mass of landlocked land.And it's in the Permian period that we meet the ancestors of the very first dinosaurs, but more on those bad boys later...

Phorusrhacidae (or 'Terror Birds')

In the wake of the mass extinction 65 million years ago that left all of the non-avian dinosaurs for dead, the Cenozoic period saw the first and only time in Earth's history that BIRDS were the #1 predators on the planet. And no bird was more terrifying than Phorusrhacidae (or Terror Bird, if like me you can't pronounce that mess of consonants either) ---->

With the largest fossil found measuring one of these bad boys at 9.8 feet tall, and beaks at an estimated 18 inches long, scientists have also reached the terrifying consensus that the Terror Bird was carnivorous, and an extremely fast and nimble runner. They inhabited South America and preferred ambush tactics to hunt their prey.

They disappear from the fossil records 1.8 million years ago, and their demise is thought to be the result of climate change in the Andes' Mountain Range, which meant that the forests became open savannahs with less places to sneak around, rendering the Terror Bird's ambush tactics less effective. Just to add to their problems, 3 million years ago the 'Great American Interchange' - the moment where the landbridge betweeen North and South America finally joined - meant that species previously separated by separate land masses were now free to mingle, and predators like Smilodon (see below) challenged the Phorusrhacidae, in what is one of countless examples in the Animal Kingdom of a Whitney/Mariah situation emerging. 

Second Supereon

In our geological timescale, the Precambrian supereon (from 4.6 billion to 541 million years ago) set the stage to prepare our favourite players from the Animilia Kingdom to shine bright like the weird, wonderful and motile multi-cellular organisms that they are. In the Hadean eon, we are searching right at the back of grandpa's broom cupboard, and finding the earliest evidence of anything and everything. We say hello the formation of Earth itself, welcome the formation of our moon, and start to get serious about photosynthesis.

   But it is not until the as-yet-unnamed second supereon that we start to see the huge diversification of animal life, a process that started to really take wind during the Cambrian Explosion 541 million years ago.  During the Cambrian radiation , the spotlight shone on protists, a group of microorganisms made up of, amongst others, protozoa ('proto' - first, 'zoa' - animals), which were able to transform complex food particles into energy.

   The early protozoa were probably plant-eating organisms to begin with, but as food resources got scarce, the herbivore policy was forced to change and the process of hunting other microbes for food started - thus causing an early version of what we know as a food chain. This in turn caused evolutionary pressure to favour mutuations which enhanced defensive, sensory and mobility mechanisms. The protozoa also evolved protective strategies by way of organising themselves into large colonies, which was beneficial for protection from predators, and this led to the organisation of larger and more complex groups that would later evolve into metazoa - multicellular animals - ie, eventually you, me and the cat next door.

 And so, following possibly the shortest summary of the first 4 billion years of Earth ever, this blog PANGEA will look at some of the most unusual and interesting examples of metazoa that have graced our curious little planet. 99.99999% of all species that have lived here are now extinct - either through competitors, changing environment or evolutionary change - and this is a celebration of some of the weirdest and best.