Messel: An Ancient Greenhouse Ecosystem

I love fossils. How can you not? The preserved remains of organisms no longer here. A glimpse into life so far back in time we can’t even begin to contemplate its vastness. Evidence that this was a real creature. Alive. Moving. Breathing. They really are incredible. What is even more incredible is that it’s extremely rare to become a fossil. An animal needs just the right conditions: to be quickly buried so no scavengers to pull apart their bodies, and fine sediment lacking oxygen so there are no worms or other critters in the mud to munch away at them.

That’s only the beginning. Once buried the body has to survive the intense pressure as tonnes and tonnes of sediment falls on top. After the body is replaced by minerals it’s not over. There’s the rocks being moved: pushed deep down, or thrust above land. The remains could easily be destroyed. With all this movement rocks will often heat up and melt, removing any evidence that life was preserved. If, eventually, the rock is finally exposed for a lucky fossil hunter to find it, there’s the risk that the rain or sun could destroy it first. There is an awful lot of luck involved whether or not an organism is fossilised. An awful lot.

Some scientists suggest that 99.9% of all organisms that have lived on Earth in the last 3 billion years have not fossilised. That’s an enormous number of animals and plants that have lived at some time in the past. What we see in museums is just a tiny fraction of life that was once here.

The beautiful fossil of Sinosauropteryx from China. A small dinosaur from the Cretaceous, the preservation is exceptional! The fine feathers covering the body have been preserved. (Image Public Domain)

There are some fossil sites that give extraordinary views into the past. The Burgess Shale in Canada and Quingjiang site in China, preserve dozens of animals that swam in the seas when large life really began 540 million years ago. Rancho La Brea, in California provides a snapshot of the Late Pleistocene life in and around Hollywood. China is discovering beautifully preserved dinosaurs, lots with their feathers still showing. There is one fossil site that I remember seeing brought alive by David Attenborough’s Lost World series: the Messel Pits in Germany.

I was delighted to receive a new book all about Messel to review. When I tore open the padded brown envelope, I carefully pulled out the book, and flicked through the pages. I actually gasped. It was beautiful.

Messel: An Ancient Greenhouse Ecosystem.

Edited by Krister Smith, Stephan Schaal and Jörg Harbersetzer, Messel: An Ancient Greenhouse Ecosystem is dedicated to the Messel Pits. These editors are all specialists who have worked for decades at the Senckenberg Research Institute and Natural History Museum in Frankfurt. The chapters are all written by experts from across the world, who are all leaders in their field in their certain topics. It was a little disappointing to see that only 5 collaborators out of 28 were women. A better balance would have been nice to see.

It’s split into easy chapters, about the site, the ecosystem, and the animals they have found. The title of the book, Messel: An Ancient Greenhouse Ecosystem, gives it away that it’s not really a book written for the general public. The text needs a lot of background knowledge, sentences are pretty long, and it’s not that welcoming to the non-expert. It’s not a popular science book. It’s not a quick-reference guide. And actually, that’s okay. Because it is a beautiful book. The non-expert can still learn a lot from it.

The Messel Pits are a pretty spectacular site. Near the little village of Messel in Germany, oil shale deposits have been mined since the 18th century. The first fossils were found in the late 1800s, and since then thousands have been excavated. Messel Fossil Pit became a UNESCO World Heritage site in 1995. And with very good reason. The fossils here are exceptional. They are so well preserved, the soft parts can be seen. Hair can be seen. Even the wings of flies can be seen.

The stunning fossil of Masillamys, an extinct, early rodent. (Image Public Domain)

Around 48 million years ago, collapsed volcanic craters formed deep lakes in the Messel area. Over around a million years the lakes filled up with sediments. These sediments are packed with incredibly preserved fossils. So well preserved because the sediment was very fine, and the bottom of the lake was deep enough that there was no oxygen, so there were not many animals living there to eat up any dead animals that fell down there. There are not just fossils of freshwater animals like fish and turtles, but lots of land animals too, from insects to monkeys. With so many land and water animals being found in the sediments, it looks like the collapsed volcanoes were still a little active, and their rumbling insides released gas (like carbon dioxide and hydrogen sulphide), which suffocated the animals.

I love how the book chapters take you through the different groups of animals and plants that have been found. Not only are the photos of the fossils some of the sexiest photos you will ever see, but they show you how incredibly rich life was here 48 million years ago. The insects are spectacular. With images and detail, we discover giant ants, weird flies, and stunning jewel beetles. The reptiles are unreal, with exquisite detail of their skeletons. And the mammals are just spectacular, clearly showing the outline of the fur. Even if you just got the book for the photos of these remarkable creatures, it would be more than worth it.

A beautiful jewel beetle from the Messel Pits. (Image Torsten Wappler, Hessisches Landesmuseum Darmstadt Public Domain)

The book isn’t a coffee table book full of beautiful photos. It brings together all the research from the study of the incredible finds. The history, the delicate, painstaking preparation of the fossils, the most up to date discoveries are all included in this book. X-rays, 3D scans, reconstructions all help to place these extinct creatures on the tree of life.

All the amazing fossils that have been found here show us what life was like here 48 million years ago. It was an incredibly rich ecosystem. In the forests alongside the lakes, there were early horses, giant ants, crocodiles, snakes, bats, monkeys and so many more species. It was an environment as rich as a tropical rainforest is today. This unique site lets us look in unbelievable detail at what life was like here 48 million years ago. This book gives so much detail about life here, you can’t help but be transported back in time.

Written by Jan Freedman (@JanFreedman)

Smith, K. T., Schaal, S. F. K., & Hebersetzer, J. Eds. 2018. Messel: An ancient Greenhouse ecosystem. Senkenberg. [Book]

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Branching out!! A review of The First Foresters: explore the Neolithic in Scotland’s Native Woodlands by Kim Biddulph and Matt Ritchie.

Do you remember your first time? The first time you realised the millennia which had existed before you, I should say!  Maybe it was standing on a hill and looking onto a landscape below scattered with raths and mounds, or perhaps a family trip to some rugged moorland, where silent grey stones maintained their tolerant silence no matter how many times you climbed on them. Or perhaps it was a random flint arrowhead or fossil found, in river or at seashore, holding time in the palm of your hand. Do you remember that fleeting moment when you felt the weight of the ages which came before you, as soft as a feather on impact, but leaving your imagination racing,  when you realised that  people far beyond your grandparent’s time had lived, loved, worked, died, believed things we knew nothing of and lived a very different life. And yet… were they so different?

That is a moment many of us have no coming back from, and it’s important. The wonder of the child spills into a lifetime of curiosity in palaeontology, palaeoecology and archaeology. This is why it is important, in this post-truth time of rewritten false pasts, to establish clear and critical thinking in a way children can deal with, while also appreciating and marvelling at the past. So, I call exhibit A , which demonstrates a clever and lively way forward, providing a strong emphasis on the skill of storytelling, of being out of doors, respect for nature and the forest, plus connecting with our ancient past. I present to this blogging jury The First Foresters: Explore the Neolithic in Scotland’s native woodlands by Kim Biddulph and Matt Ritchie.

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The First Foresters, released April 2019, by Kim Biddulph and Matt Richie

Quite simply, nobody does archaeology and environmental awareness and promotion better than Scotland, and this project is a joint venture between Archaeology Scotland, Outdoor and Woodland Learning and Forestry and Land Scotland. Kim Biddulph is no stranger of course to the Beast Team, having had us on her podcast talk about all sorts of things, but mostly Jean Auel books!  You can listen to that one right here but she’s also active in many educational facets of British archaeology.

Matt Ritchie was responsible for the highly imaginative and creative commissioning of this book. He is an archaeologist and National Environment Advisor for Forestry and Land Scotland. His ‘ordinary’ (does that word apply to archaeology? I’d argue no!) work involves the protection, conservation and presentation of the historic environment in Scotland’s national forests. There was also extra input from Dr Gavin McGregor and Ingrid Shearer of Northlight Heritage. The lavish illustrations  are by Alan Braby and Alice Watterson, photography by John MacPherson, and a set of very human characters created Alex Leonard and Kim Biddulph. The linocut artwork is by Liz Myhill, while the maps and plans were drawn by Headland Archaeology. The ubiquitous National Museums Scotland contributed images of stone axes.

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Meet the Neolithic family! The clan created by Alex and Kim to tell the story of the first farmers of Scotland.

The text is primarily for use with Level 2 children (that’s ages 7 to 11 for other parts of the world) under the Scottish Government’s Curriculum for Excellence education manifesto. That being said, a tweak here and there could be applied to the material and probably engage awkward Freshers to have some getting-to-know-you fun in a seminar.

The 1500 years of the Neolithic, from around 4000 BC to 2500 BC, is one of the most important historical phases in European human history, as it is the period when the Twilight Beasts of these islands truly did fade into legend. New ways of living came lapping onto the land, as steadily as a rising tide.  Humans became settled in one place, adopted agriculture, destroyed forests to claim farming land, and animals became domesticated. This period redefined the Mesolithic relationship with creatures and the environment.

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One of my own photos of the Neolithic stones of Kilmartin Glen, a timeless place where sheep still graze, just not the same breeds! For a bit more on Neolithic sheep types, try here

This little book contains a potent emphasis on environmental awareness, incorporated with attention to structures and material culture, such as timber circles and cursus monuments of the Neolithic, as well as polished stone axe heads, before challenging the participant to enter into a Neolithic mind-set – and asks is that even possible in the modern world? That’s surprisingly deep question that most adult experimental archaeologists will sigh, shrug and smile wryly at. Not a bad idea to make kids realise that we cannot ever step in the same river twice! My personal favourite activity is the construction of a wooden circle in class. I remain slightly relieved that my own daughter is not an age where this would have caught the imagination too far, and I’d have woken up surrounded by a ritual mound of books and shoes… though you never do know! It’s an activity I could see being incredibly useful , with a  few more analytical tweaks, to the average First Year undergraduate archaeology student.

The section dealing with the Neolithic mind allows an exploration of what is believed, and why, and how cultures and ideas change. It explores in an easy to understand manner how Neolithic land use brought rules connected to the cycles of growth, tethering humans as much as animals to domestication, and how forests represented primeval, uncontrollable forces. This may well be very different from the earlier hunter-gatherers of the Mesolithic, who followed more fluid rhythms of nature set by the movement of creatures. The text also acknowledges, humans being the contrary being they are, that there were also groups who didn’t quite conform to either 100% Neolithic or Mesolithic trends!

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One of the wonderful illustrations by Alan Braby, coloured by Ian Kirkwood, of a defleshing platform. During the Neolithic, bones were likely picked at open air sites ( The Giants Ring at Ballynahatty, outside Belfast, is one such site), then the clean bones were interred in cairns, elsewhere. Look at the little ‘Westray Wife’ figure in the midst of all this!

The book also presents a very welcome realistic expectation and explanation of what archaeologists actually do, which of course can make young’ns consider it as a genuine career choice. There’s a strong emphasis on the skill of storytelling, of being out of doors, respecting nature and the forests, and directly experiencing the heartbeat of nature, faint though it may be in the modern world, drowned out by bleep and purr of smartphone and Chromebook.

Lavish illustrations are museum adventures waiting to happen, encouraging observation of objects on display – the little carved wooden idols, the pots and the stone axes. They are on the right side of imaginative and full of verve in their use of bright primary colours, reminiscent of a colouring book.

All in all, this book is a delight to introduce young folks to the environment, archaeology and how we interact with the past – and it with us. If you have young ones, use the book on walks and trips. They, and possibly you, may never look at the landscapes and forests of wherever you are without asking lots of questions and thoughts.

And do you want to know the best bit of it all? You can download it free of charge, gratis, for nowt, right here!

https://forestryandland.gov.scot/images/learn/archaeologyandheritage/The-First-Foresters.pdf

What are ye waiting for? Go get out of doors, and look for the Neolithic!

 

Other places to check apart from the links provided? 

https://www.scottishheritagehub.com/

https://www.historicenvironment.scot/

Home

https://www.digitscotland.com/

https://archaeologyscotland.org.uk/learning/

 

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Remarkable creatures

Armadillos are pretty cool animals. They’re pretty weird too. They kind of look like odd small pigs, with crazy sharp claws. What’s more, they are covered in a pretty tough armour topped in even tougher scutes. The scutes alone are pretty spectacular. Think of a carrot cake topped with cream, only the carrot cake is solid bone, and the cream is horn: a unique adaptation in the animal world. This protection covers their back, on the top of their heads like a helmet, and even overlapping rings covering their tail. What is quite amazing, is that unlike their ancient relative, those giant glyptodonts, who are covered in a huge solid shell of scutes, the protection covering the backs of armadillos is in bands. And this means that their bodies are much more flexible. If threatened, these bizarre looking creatures will suddenly curl up into a ball: a perfect, solid, impenetrable ball. They are almost invincible (apart from cars, humans, and climate change). The armour is so strong that recently a man tried to shoot an armadillo, and the bullet ricocheted off it and hit him! (Karma).

The nine-banded armadillo in Florida. These remarkable animals are covered head to tail in super-strong armour. (Image Public Domain)

Regular readers wouldn’t be surprised to hear that until fairly recently there were some darn big armadillos. And this is their story.

The unseen, never slowing, forces below our feet, those tectonic plates that all oceans and land float upon, are powerful enough to rip continents in half. And this is what happened around 140 million years ago. South America and Africa were once joined together until the tectonic plate it sat on split into two. (Have a look at a map and you will see that South America and Africa fit together perfectly like a jigsaw. In fact it was this jigsaw that helped lead to the theory of plate tectonics, or continental drift, by Alfred Wegener in 1912, and was proved true by seismic and magnetic observations in the 50s.)

Back to our story. Here was one massive island, cut off from the rest of the world for a very, very long time. The animals that were trapped adapted and changed in isolation: in a constantly changing environment, they competed against each other in a brutal daily race for survival.

Of all the myriad of forms that evolved in South America, the armadillos are one of my favourites. With 21 species around today it is a relatively large family, including the more familiar nine-banded armadillo, the adorable pink fairy armadillo, and the slightly terrifyingly named screaming hairy armadillo. Perhaps surprisingly, the closest living relative of our adorable, shelled friends are the ever-lovable sloths, both belonging to the group Xenarthra. Diverging around 65 million years ago, the armadillos went on their own evolutionary path, and the sloths slowly went their own way.

The slightly odd, but utterly adorable screaming hairy armadillo. (Image Arnaud Boucher)

Early armadillos faced many pressures from predators and environmental changes. To adapt and survive, some populations branched off, evolving into new beasts. Around 47 million years ago, some early armadillos took advantage of eating tougher vegetation, and getting bigger, evolving into a new family of large creatures, the Pampatheriidae. Evolution isn’t simple. Nor is it neat. There is no ladder of progression only a crazily bushy tree of new species branching off while old species either carry on living for millions of years or succumb to the pressures around them. There is nothing preordained. Just luck. The right trait at the right time. The environment is in control. And if animals cannot adapt, they die.

With several genera (containing over a dozen species), the Pampatheriidae were a pretty big family. One genera in particular had some of the largest armadillos: Holmesina. There were six species, H. floridanus, H. occidentalis, H. major, H. paulacoutoi, H. rondoniensis, and the largest of them all H. septentrionalis. Their teeth show that unlike today’s armadillos, who gorge on insects, Holmesina ate tough plants. Eating hard plants would have worn down teeth very quickly and would be a problem for us if we were to change our diet. But these extraordinary giants had a pretty neat adaptation: ever-growing teeth, like a rodent. There was no fear of them wearing down.

One of the largest of the pampatheriidae, Holmesina septentrionalis, compared to a 6 foot tall human.

Modern armadillos have big strong claws which they use for digging up grubs and making burrows. The burrows are their homes, providing a little cosiness from the external weather, and safety from predators for the youngsters. Holmesina too had large claws. They may have used these to dig burrows. There have been some exceptionally large burrows discovered on rocks in South America. Burrows dug into rock! These have been attributed to giant sloths and glyptodonts by matching the tunnel size and the claw marks left in the walls. Holmesina may have preferred softer soil. Or it could be that we haven’t found their burrows in rock. Yet.

The beautiful foot of Holmesina septentrionalis in the collections at Florida Museum. (Photo kindly reproduced with permission by Rachel Narducci)

After million years of isolation, something happened that would have a huge impact on all life on that huge isolated land. Massive underwater volcanic eruptions created a land that connected North America to South America. The Isthmus of Panama is a true land bridge. For the first time in over 137 million years, species were able to move between the two continents. Sabre tooth cats, Gomphotheres, horses, and many more moved into South America from North America. And species moved from South America northwards too, including terror birds, toxodon, giant sloths, glyptodonts, and our giant armadillo, Holmesina. With this new movement of species, there was extra pressures on the endemic animals, with new predators hunting prey that had no defences. Holmesina, it appears, did fairly well. Numerous fossils have been found in Texas and Florida, as well as it still thriving in South America. They were the most widely distributed pampatheres.

The huge, massive, and somewhat remarkable creature, Holmesina septentrionalis. (Image Public Domain)

Their extinction is an enigma. Fossils hint that the last Holmesina were around until just 11,000 years ago. This coincides with other large scale extinctions of megafauna across North America. Humans have been implicated as the cause for many of these glorious giants vanishing. And there are some signs that humans definitely interacted with them, including spear points found in embedded in bones, and cut marks on bones. But Holmesina? There are currently no fossils found showing that humans interacted with them. No roasted giant armadillo on the menu. No manipulated Holmesina shells for homes or body armour (which would have been fascinating to see). If modern armadillos are anything to go by, they would have been pretty difficult to kill, although the youngsters may have been easier prey.

So what happened to them? It is difficult to say for sure. They were pretty specialist creatures, and the more specialised an animal is the more vulnerable it is to rapid changes in the environment. We know that the climate was undergoing global scale changes, with the glaciers covering most of the northern hemisphere shrinking back and new types of vegetation replacing the old. It is more than likely that these changes had a big effect on our giant armadillo.

The Pleistocene was full of amazing creatures. Some so weird that they would have been baffling to see today, like the massively bizarre Toxodon, or the weird trunked horse-like Macrauchenia. But others strangely familiar, like the enormous Columbian Mammoth, or the giant armadillo. To have seen a giant armadillo would have been a magnificent sight. And to witness one roll into a ball? Well that would put a smile on anyone’s face.

Written by Jan Freedman (@JanFreedman)

Thank you to Rachel Narducci, at the Florida Museum of Natural History for her feedback on an early draft of this post. (Follow Rachel on Twitter for some cool research with pampatheres: @renarducci)

Further reading:

Billet, G., et al. (2011). ‘Oldest cingulated skulls provide congruence between morphological and molecular scenarios of armadillo evolution.’ Proceedings of the Royal Society. 278 (1719). p. 2791. [Full article]

Delsuc, F., et al. (2016). The phylogenetic affinities of the extinct glyptodonts.’ Current Biology. 26(4). pp.155-156. [Full article]

Flavio G., et al. (2015). ‘A peculiar New Pampatheridae (Mammalia: Xenartha: Cingulata) from the Pleistocene of Argentina and Comments on Papatheriidae Diversity.’ PLoS ONE. 10 (6). Eo128296. [Full article]

Gaudioso, G., M., et al. (2016). ‘Paleofauna del Pleistoceno de Termas de Rio Hondo, Santiago del Estero, Argentina.’ Ameghiniana. 53(6). p.54.

Mead, J. I., et al. (2007). ‘Late Pleistocene (Rancholabrean) glyptodont and pampathere (Xenarthra, Cingulate) from Sonora, Mexico.’ Revista Mexicana de Ciencias Geologicas. 24(3). pp.439-449. [Full article]

Slater, G., et al. (2016). ‘Evolutionary relationships among extinct and extant sloths: the evidence of mitogenomes and retroviruses.’ Genome Biology and Evolution. 8(3). pp. 607-621. [Full article]

Woodburne, M. O. (2010). ‘The great American biotic interchange: dispersals, tectonics, climate, sea level and holding pens.’ Journal of Mammalian Evolution. 17(4). pp.245-264. [Full article]

Vizcaino, S. F., et al. (1998) ‘Skull shape, masticatory apparatus and diet of Vassallia and Holmesina (Mammalia: Xenartha: Pampatheriidae): When anatomy constrains Density.’ Journal of Mammalian Evolution. 5 (4). pp.291-322. [Full article]

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Smilodon: The Iconic Sabertooth

Smilodon: The Iconic Sabertooth

I recently bought this book (with my own money, this is an impartial review: I can’t be bought, man!). “Smilodon” is somewhat of a companion volume to another recent-ish release, namely “The Other Saber-tooths: Scimitar-tooth Cats of the Western Hemisphere”. Both volumes come from Johns Hopkins University Press. Whereas “The Other Saber-tooths” deals with the less well known Homotherini tribe of the machairodont subfamily, “Smilodon” jumps into the gap containing the extinct superstar Smilodon, and the tribe Smilodontini.

First things first; this is a technical book. It is not really intended for the interested lay-reader but organised as essentially a collection of totally independent papers bound together for use by specialists in the field. It follows from the International Sabertooth Workshop that took place in 2008. It assumes a reasonable amount of familiarity with extinct cats, their anatomy, and their fossils.

The volume is pretty wide-ranging and contains a host of sabretooth experts. The editors are Lars Werdelin, Chris Shaw, and Greg McDonald who all have decades of experience in Pleistocene matters.

There is an introductory chapter on the convoluted history of how a carnassial tooth from Texas came to be the Holotype for Smilodon fatalis, and the role material collected by the great Danish naturalist Peter Lund had in erecting the species Smilodon populator. Anyone who has investigated the taxonomy of a wide ranging fossil species will know that they are usually complicated by numerous binomials having been given to what are essentially the same taxon. Smilodon is definitely one of these with at various times and places the genera Trucifelis, Machaerodus, Munifelis, Hyaena, and Felis used for different bones and teeth. One interesting tidbit, unknown to me is that Lund’s original use of Smilo-(sabre) and odon-(tooth) actually referred to the crooked shape of the incisors and not the enormous canines, which were incompletely known at the time. This chapter is beautifully illustrated with exquisite lithographs culled from various nineteenth century sources, finer than any photograph.

Holotype teeth of Smilodon fatalis, from Hardin County, Texas. Figured by Joseph Leidy. Public Domain

Canine of Smilodon populator, part of the type series described by Peter Lund and in the Copenhagen museum. Image © the author

Skull of Smilodon populator from the Lund collection in the Copenhagen museum. Image © the author

Chapter 3 focuses on the little known tar pit of Talara, Peru. Many, if not most folk interested in ice age animals will have heard of the famous Rancho la Brea tarpit in downtown Los Angeles, with its millions of bones and thousands of sabretooths and dire wolves. Less well known is that there are other tarpits in Venezuela and Peru that have similar collections of extinct monsters. Talara, in Peru has given nearly two thousand Smilodon bones, from at least twenty-four individuals, for study. It’s a very important site, not just for the raw number of bones but because the western Andes seem to be the southernmost extension of the range of North American S. fatalis, specifically distinct from the larger S. populator that is found east of the Andes. Detailed study of the Talara material in this chapter gives insight into sexual dimorphism, ontogeny, and sociality. It is, after all, the second greatest concentration of sabretooth bones known.

Chapter 4 deals with an amazing site, and one very close to my heart. Cueva del Milodón is Chile’s southern Patagonia is just incredible. The very first bone samples I ever analysed as a brand new PhD student were from this site, a site that has given us giant sloth skin, hair, bone, nails and dung, along with bones of sabretooths, giant shortfaced bears, giant jaguars, pumas, llamas, macrauchenia, deep-nosed horses, warrah-wolves, and other species. Right at the tip of South America, the climate is such that the preservation levels in the cave have perfectly captured a snapshot of a lost world of Pleistocene megafauna. The bones of Smilodon populator get a proper write-up and description. Most interestingly, tabulation of the data seems to show that Smilodon obeyed Bergmann’s rule i.e. individuals at higher latitudes were in general larger than those at lower latitudes.

My friend Alex at Cueva del Milodón in Chile. Image © the author

The inside of the cave. (Image from Wikimedia Commons by Dan Lundberg)

Selection of Smilodon populator bones from Mylodon Cave. Image © the author

Some of the nails, skin, and dung from the cave. (Image from Wikimedia Commons by Ghedoghedo)

Chapter 7 uses the infamous “Robocat”, an invention of my friend and colleague Todd Wheeler. For those who don’t know, “Robocat” is a hydraulic trackhoe, modified with a scale steel model of Smilodon skull and mandible attached to a rig that approximates the movement of the lower neck and other muscles. Using a spare bison carcass, “Robocat” continues the fine tradition of experimental palaeontology in trying to figure out how the heck sabretooth cats used their enormous teeth. The bison gets spectacularly mangled in the process. Interestingly the classic canine shear-bite first proposed by Bill Akersten in the 80s may not be feasible but based on the “Robocat” experiments a different bite model may be needed. There is also an interesting discussion on fossil Smilodon canines from older animals that seem to have suffered gum disease and allowed the tongue to rasp away a groove in the dentine. A subtle but evocative sign of soft tissue in this extinct cat.

Chapter 10 uses stable isotopes to look at what the species of Smilodon were eating and where they were hunting. It basically confirms earlier work showing that browsers were the main prey, things like ground sloths and macrauchenia. Hunting grounds were also open forest areas, which makes sense for a large ambush predator.

Chapter 12 is a fascinating overview of palaeopathology in Smilodon from that immense collection of Rancho la Brea. Bones showing massive infection, pathological fusion of vertebra and other examples of disease are discussed and put in the context of behaviour in Smilodon.

Other chapters deal with morphological phylogenetics in sabretooths, Smilodon fossils from South Carolina, computational biomechanics of the Smilodon skull, tooth development of Smilodon, postcranial morphology, and skull evolution.

Overall, this is a handsome and well put together book. The illustrations that accompany each chapter are good. There is a wealth of information about Smilodon, and much that is new and interesting. There are colour plates showing a range of reconstructions of Smilodon through the ages, from pioneers like Charles R Knight, to modern masters of palaeoart like Mark Hallett and Mauricio Anton. Curiously, these are not referred to in the text at all and simply serve as a series of canvases illustrating the eponymous subject of the book.

Given that the work is a collection of papers by different groups there is the inevitable repetition of some key Smilodon facts in almost every chapters’ introductory paragraphs. Nonetheless, it is no mean feat to pull together such a breadth of scholarship on a single subject into a coherent whole. In that sense “Smilodon: the iconic sabretooth” succeeds.

My only negative comments are that it does not succeed as well as its companion volume “The Other Saber-Tooths: Scimitar-tooth cats of the Western Hemisphere”. For my money, “Other Saber-Tooths” is a more pleasing volume, with richer illustrations and better integration of chapters overall. Still, I will leave with this final endorsement:

Both books are absolutely deserving of a place on the bookshelf of any fossil felid aficionado.

Written by Ross Barnett (@DeepFriedDNA)

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Globe trotter

Horses are one of Europe’s last big mammals. They shouldn’t really be here: they should have vanished a long time ago with most of the other large mammals from the Pleistocene.

Europe once had herds of gigantic, hairy mammoths; solitary, shaggy woolly rhinoceros; deer with antlers wider than I am tall; and so many more. Unfortunately they are gone. Missing from our landscape. A combination of climatic changes and human hunting resulted in these unique creatures disappearing from our beautiful world forever. With the shifts to a warmer climate from around 30,000 years ago, the environment that supported these beasts changed. Many populations diminished, as habitats shrunk. With dwindled numbers, the additional stress of humans was too much for most animals to bounce back from. The killer blow was not just for an individual but for the entire species.

Horses had the same challenges as other large mammals. The grasslands shrunk, limiting their food. And humans really enjoyed horse meat: a myriad of archaeological sites across Europe are full of horse bones with cut marks on them. And there are many sites in North America showing butchery (yes, horses were at home in North America until just 10,000 years ago!). Yet they are still in Europe today. It seems that the very thing that finished off most of the other mega-fauna was key to the survival of horses: humans. Our species saw that they could be used: not for meat, but to help carry things, and even ride. Archaeological evidence is most convincing at Botai, in Kazakhstan, where around 5500 years ago, horses were being used as milk animals (as opposed used for just meat) as well as  being used as transport by humans. Jars which contained mares milk still hold traces of the milk lipids,  and there is evidence of  cheek-pieces in use, showing the animals were bridled to go the directions the humans wanted. The  speed and quicker breeding cycle of the horse, compared to some of the larger mammals, certainly helped them survive, but by being ‘useful’ to humans ensured they are still here today. They are the last line of an amazing group.

The gorgeous Przewalski horse, a rare and endangered wild horse. (Image Claudia Feh. Public Domain)

The first animal that can be called a horse was on Earth around 52 million years ago in North America. Poetically named the ‘dawn horse’, Eohippus was about the size of a sheep dog, living in luscious tropical rainforests. With four hooved toes, it was pretty nippy in the forests, browsing on leaves and fruits. Despite its size, Eohippus travelled across the northern hemisphere: from North America into Europe, and was around for around 9 million years.

Climatic changes during the Eocene saw the tropical rainforests of North America being replaced by grasslands. Grass is such a familiar part of our lives, we take it for granted. It is one of the most widespread of all plants, and has evolved into an unfathomable range of over 12,000 different species across the globe, colonising every continent. With this tough, fast spreading plant, some herbivores adapted to taking advantage of it as a very easy source of food. Early horses moved out of their tropical rainforest homes to take advantage of the rich grasslands. But grasses are tough. Many contain silica phytoliths, which is tough and wear down teeth pretty quickly. These hooved little animals adapted to the more abrasive food by evolving higher crowned teeth: they were stronger and longer wearing down slower. With more open environments, species began to lose toes making them faster to escape predators. Dozens of species were around from about 36 million years ago all surviving, adapting, changing along with the constant pressures around them.

Through time horse species saw a reduction in toes, a flatter skull and thicker teeth. (Image H. Zell. Public Domain)

One genus was extremely successful. Evolving around 22 million years ago in the Miocene, Hipparion have been galloping across the planet until just around 780,000 years ago. This is an extremely long time. Especially when you consider our Genus, Homo, has only been around for a little over 2 million years, whereas Hipparion had been on Earth for 22 million years.

If you saw Hipparion today, you might think it was a modern horse, albeit a slightly smaller one. It would have looked like a modern horse in almost every respect, apart from a tiny difference. Hipparion had two small toes, not touching the ground, just above each hoof. These are vestiges of this animals past. Hints that the ancestors of Hipparion once walked on more than one hoof. With a need for speed, one hoof is much faster for such a large animal then three toes, so through time the toes shrunk.

Hipparion, almost the same as a horse you love and know. But it wasn’t. (Image Twilight Beasts)

There were several species of Hipparion across the northern hemisphere. From North America, they galloped into Europe, Asia, and even down into Africa. Sadly they were a lonely twig on the tree of life, leaving no descendants. Some species of Hipparion shared the land with our own ancestors. Incredible footprints preserved in 3.6 million year old volcanic ash at Laetoli in Africa show Australopithicus afarensis walked close by to a number of Hipparion. Homo erectus in Europe and Asia may well have come across this speedy herbivore. No bones have been found yet to show that hominins hunted or ate these horses. There were probably much easier, slower, prey to be had.

Unlike the other Late Pleistocene extinctions, humans were not to blame for their disappearance. The climate may well have been a big impact. With cooling temperatures grasses spread, and with expanding rich land new species of grazers, like mammoths and modern horses. This would have been new competition, pressure on resources, and lots of new predators. All these different factors would have had a huge impact on populations of Hipparion, slowly pushing them to the edge of extinction.

Extinction happens. Animals are in a constant struggle for survival. Faster predators. Changing climate. Better competitors. Sometimes when you play survival, you win or you die. There is no middle ground.

Written by Jan Freedman (@JanFreedman)

Further reading:

Buck, C. E. & Bard, E. (2007). ‘A calendar chronology for Pleistocene mammoth and horse extinction in North America based on Bayesian radiocarbon calibration.’ Quaternary Science Reviews. 26 (17–18). pp.2031–2035. [Full article]

Carroll. R., L. (1988). Vertebrate Palaeontology and Evolution. W. H. Freeman and Company, New York. pp. 1-698. [Book]

MacFadden, B. J. (1976). “Cladistic analysis of primitive equids with notes on other perissodactyls”. Syst. Zool. 25 (1). 1–14. [Full article]

MacFadden, B. J. (1984). ‘Systematics and phylogeny of Hipparion, Neohipparion, Nannipus, and Cormohipparion (Mammalia, Equidae) from the Miocene and Pliocene of the New World.’ Bulletin of the American Museum of Natural History. 179. pp.1-195. [Abstract only]

MacFadden, B. J. (1998). Equidae. In Janis, C.M, Scott, K. M., & Jacobs, L., L. (eds.), Evolution of Tertiary Mammals of North America. pp. 537-559. [Book]

MacFadden, B. J. (2005). “Fossil Horses–Evidence for Evolution”. Science. 307 (5716). pp.1728–1730. [Abstract only]

Orlando, L. et al. (2013). ‘Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse’. Nature. 499 (7456): pp.74–8. [Full article]

Solow, A., Roberts, D., & Robbirt, K. (2006). Haynes, C. V. ed. ‘On the Pleistocene extinctions of Alaskan mammoths and horses.’Proceedings of the National Academy of Sciences of the United States of America (19 ed.). Proceedings of the National Academy of Sciences of the United States of America. 103 (19): 7351–3. [Full article]

Weinstock, J., et al. (2005). ‘Evolution, systematics and phylogeography of Pleistocene horses in the New World: a molecular perspective. PLoS Biology. 3 (8): e241. doi:10.1371/journal.pbio.0030241.

Posted in Horse | Tagged , , , , , | 3 Comments

The most (and least) read posts of 2018!

A year goes far too quickly. But a lot has happened. Rena is now Dr Rena after successfully completing her PhD. Ross has finished his book (The Missing Lynx) which is coming out in Summer 2019 (very exciting!). And Jan is beavering away at his museum. We also have some Twilight Beasts T-shirts, cups and other bits that you can buy!

With the end of a year comes the time when people pull together their ‘top ten’ greatest moments. We like to pull out the top 5 blog posts of the year. But we also like to highlight the bottom 5. In our eyes all of the posts are amazing, and why not share 10 great ones again? Browse through these 10 posts and immerse yourself in these incredible creatures of the recent past!

 Least read blog posts of 2018:

  1. How do you weigh a Dodo? This is a question I have always pondered. Now you can find out! Plus it has lots of lovely dodo pictures.

A fierce, slim looking dodo by Carolius Clusius. (Image Public Domain)

 

2. Baby’s got quack: We like the witty titles. This one is about an enormous Japanese duck.

3. The ancients of the forests: Some trees in New Zealand are a geed few thousand years old. They are incredibly important to the ecosystems.

4. Getting inside the bones: Take a look at what scientists re doing to help identify bones in museums.

5. Side by side with Homo: Discover one of our weirdest relatives. The chunky, robust Paranthropus.

The robust skull of Paranthropus boisei (Image Bjørn Christian Tørrissen, Public Domain)

 

The most read blog posts of 2018:

  1. A striped wonder: One of the saddest tales of extinction. The beautiful Thylacine. Gone forever.

A male and female Thylacine in Washington D.C. National Zoo. (Image E.J. Keller. Public Domain)

2. Under the boot of man: Another horrific extinction. This time, the Great Auk. The last egg of a great auk was crushed by a hunters boot.

3. Going underground: There were once giant ground sloths on Earth. And they dug ENORMOUS tunnels!

4. From Russia with love: Not only does this blog post have an exceedingly clever title, it is all about the most beautiful woolly mammoth so far discovered.

5. The End of the Ice Age: This is the first time a book review has made it into the top 5. And it’s a fantastic book, so well deserved!

 

From the three of us at Twilight Beasts, we wish you a very healthy, happy, and fun 2019! We look forward to sharing lots more beasts with you!

Rena (@JustRena), Ross (@DeepFriedDNA) and Jan (@JanFreedman).

Follow us on Twitter  (@Twilightbeasts)  and Instagram (@TwilightBeasts)

Posted in Celebrate! | Tagged , , , , , , , , , | 2 Comments

You only live twice

Australia is a continent full of weird wonders. From kangaroos to koalas, the animals here are unlike anywhere else on the planet. Australia is a landmass that has drifted slowly northwards, alone, across the empty Indian Ocean for over 30 million years. After it ripped apart from Antarctica, it carried with it a small cargo of mammals that evolved and adapted to life on this huge drifting land. Unlike most other parts of the world, marsupials here thrived. These hairy, milk producing mammals differ from you or I as their young are born very early and develop in a pouch. (We are placental mammals, like cows, whales and mice, where our babies develop fully inside the mother). In other parts of the world, placental mammals outcompeted marsupial mammals: they produced more young at a quicker rate. A hundred species of marsupials cling on in South America, Central America and in the very south of North America. But with over 330 species in Australia, it is here that is the home of the marsupial. Before the arrival of Europeans, there were very few endemic placental mammals (some bats, bush rats and hopping mice): all inconspicuous under the feet of the successful marsupials.

The iconic marsupial, the kangaroo. Notice the youngster in the pouch, which can develop and grow there for (Image Public Domain)

Isolated for so long, without the competition of placental mammals, marsupials evolved into some of the most wondrous, strange animals to have walked our planet. Enormous wombats the size of a car, giant kangaroos, and deadly hunters like the marsupial lion owned the land. What an incredible sight they must have been for those first people to explore the land 50,000 years ago!

There were even weirder creatures too. Like our beast, Palorchestes, which may well have been one of the strangest of the Australian megafauna.

For over 70 years this was thought to be something it wasn’t: a creature with a fake identity. This fairly large mistake was due to the problems palaeontologists face when there are new finds. It’s not an easy task. Sometimes we get pretty complete skeletons which makes it a lot easier to compare to other living and extinct animals. Most of the time the bones are small, broken, or crushed. There are thousands of unknown animals lying in drawers in museums: parts of them that have survived erosion, scavenging, or trampling, waiting patiently for their identity to be revealed. They have waited millennia, a few more years won’t hurt them.

The well-known, egocentric Victorian scientist Richard Owen described this beast based on one fragmentary jaw. The teeth looked similar to those of a kangaroo, so he named it Palorchestes – the ‘ancient leaper’. He gave this extinct animal a name, but it would be decades until this creature’s true identity would be revealed.

For a while this animal lived as a kangaroo in the scientific world. More fossils were found of this Australian giant, and in the 1950s it was identified as a new family of marsupials, named Palorchestidae. The giant kangaroo was no more: it was born again as a new type of creature, closely related to the enormous wombats Diprotodon and Zygomaturus (belonging in the Order Diprotrotodontia). This new family includes four different genera, with only 8 species. (Taxonomy can be a bit of a headache at times. We humans are classed in the Order of Primates – along with all apes and monkeys – and we are in the Family Hominidae. There are dozens of different genera of Hominidae, most of which are now extinct. Today the family just has 8 living species including chimps, gorillas, orangutans and humans: we are in the genus Homo.)

The big, weird giant Palorchestes azeal.

This strange, small family of marsupials were extremely longed lived. Evolving in the Miocene around 11 million years ago, they possibly survived until around 40,000 years ago. It appears that there was not much overlap with different species of Palorchestes living at the same time, with the fossils suggesting that species progressively for larger through time: the largest was P. azeal.

(This view of species evolving straight into another species is often misleading. It implies that one evolved straight into another, with just that one species living on the planet. In reality, a population of one species evolved locally adapting to changes, while other populations continued to live for millennia in other parts of Australia before becoming extinct. Reading the rocks from a fossil site may show one species replacing another, whereas in other parts of the continent that extinct species was likely around for longer. The fossil record is incredibly amazing because it allows us to know more about life in the past. But it is also incredibly frustrating because we need more fossils to paint a clearer picture of what was happening.)

This beast was widely distributed across Australia and Tasmania. Fossils are not very common suggesting it was a solitary animal, similar in lifestyle to rhinos and sloths. It was utterly bizarre. Its odd skull with short bones in the nose, hints that it had a short trunk, not too dissimilar to a tapir, giving it a more common name of marsupial tapir. Structures in the lower jaw indicate a long, thick, muscular tongue. With robust front limbs with pretty big claws, and a kangaroo-like tail, our leaping marsupial was no leaper.

This strange anatomy provides clues to the lifestyle of the marsupial tapir. The consensus is that Palorchestes was a solitary, browsing animal, living in open woodlands, using the claws to pull down branches and that thick, long tongue to pluck off leaves. The claws would have been used for defence and may even have been used to dig for roots. I wonder if there was more to it than that. The giant sloths and giant armadillos in North America had huge claws, and lived in similar habitats. There is evidence in South America that some dug massive burrows. The powerful forelimbs and strong claws could have been used in a similar way for Palorchestes, providing shelter from predators and a safe way to bring up their young. As yet no huge palaeo-burrows have been found in Australia, but I like to think that one day they might be.

With so few fossils of Palorchestes, it is unclear exactly when this species became extinct.  To date there have been no fossils found indicating that humans hunted or ate them. The youngest concrete dated specimens are around 100, 000 years ago, which is a good 60,000 years off the main mega-faunal extinctions in Australia. Some fossils have been radiocarbon dated giving much younger dates, but the samples have included lots of contamination or degraded too much for the dates to be reliable.

However, there is tantalising evidence that early inhabitants of Australia may have even seen these animals.

40,000 years ago someone painted some animals on a cave wall. Is this a painting of the marsupial tapir? (Image from Oakes 2003)

There are several cave paintings in Arnhem Land, with one that has been thought to be of the marsupial tapir. This painting dates to around 40,000 years old, long after the last radiocarbon dated specimen. Perhaps this is not Palorchestes. Perhaps it is. Fossils of this creature are quite rare, and we must remember that the last radiocarbon dated individual does not represent the last individual of that species. It would be strange that it disappeared long before the other Australian giants. But then the climate in Australia was becoming dried in the Late Pleistocene, reducing the wet rainforests and woodlands. More sites with more fossils will give us more answers.

This remarkable animal has perplexed us since it was first discovered. It has lived two lives since the late 1800s, and it still have many secrets to reveal.

Written by Jan Freedman (@JanFreedman)

Thanks to Gilbert Price (@The FatWombat) his comments on the post.

Further reading:

Anderson, C. (1933) ‘The fossil mammals of Australia.’ Proceedings of the Linnean Society of New South Wales. 59. pp.ix-xxv.

Archer, M., Hand, S. J., & Godthelp, H. 1994. ‘Riversleigh: The story of Animals in Ancient Rainforests of Inland Australia.’ Reed Books, Chatswood. [Book]

Banks, M. R. Colhoun, E. A., & van den Geer, G. (1976) ‘Late Quaternary Palorchestes azeal (Mammalia, Diprotodontidae) from northwest Tasmania.’ Alcheringa. 1(2). pp.159-166. [Full article]

Black, K., & Mackness, B. (1999) ‘Diversity and relationships of diprotodontoid marsupials.’ Australian Mammalogy. 21. pp.34-45. [Full article]

Long, J., Archer, M., Flannery, T., & Hand, S. J. (2002). ‘Prehistoric Mammals of Australia and New Guinea: One hundred million years of evolution.’ Kensington. University of South Wales. [Book]

Martin, P. & Klein, R. G. (Eds) (1989) Quaternary Extinctions. University of Arizona Press. [Book]

Oakes, T. (2003) Monsters we met. BBC Books. [Book]

Owen, R. (1873) ‘On the fossil mammals of Australia. Part IX. Family Macropodidae: Genus Macropus, Pachysaigon, Leptosaigon, Procoptodon, and Palorchestes.’ Phil Trans Roy Soc. 164. pp.783-803.

Price, G. J., Feng, Y., Zhao, J., & Webb, G. E. (2013) ‘Direct U-Th dating of vertebrate fossils with minimum sampling destruction and application to museum specimens.’ Quaternary Geochronology. 18. pp.1-8. [Abstract only]

 

Posted in Diprotodon, Giant Short-Faced Kangaroo, Marsupial Tapir, Zygomaturus | Tagged , , , , , , , , , , , , | 1 Comment