Battle of the Birds

I grew up in an area on the shoulder of a forested mountain, beside a series of lakes which are speckled with modern crannogs, replacements of ancient originals which are long gone. The shores and islets are rich in birdlife, as much as frog, fish and furry critters. A couple of years ago, the local paper ran a story of a hoodlum alpha male swan who was attacking small dogs, attempting a bit of Zeus and Leda-type action on other wildlife and unwary children, and apparently assassinating his love rivals. They shipped him off to someplace else, but his flailing wings and killer instinct caused quite a stir at the time. So much for the delicacy and grace of Swan Lake, eh?  Birds are tough cookies.

Waterfowl are a particular love of mine, which is probably why I find myself writing about odd birds (okay, that, and I’m an odd bird meself). I’ve paparrazi’d birds around the world on my peregrinations. I fell rather in love with the snowy white ibis picking through the riverside fields of the southern Nile: those long beaks extracting sustenance from the waters. More humans than me have been charmed by their otherworldliness – the ibis made its enchanting way into mythology as the avatar of the Egyptian god of wisdom Thoth, who chose avian form when he popped onto earth to observe human behaviour. Thoth was a proper sort of deity – no smiting or entrapment of poor mortals. Instead, Thoth was bookish, smart, all about the readin’, writin’ and ‘rithmatic; the Egyptian pantheon’s non-violent nerd.

thoth

The ibis-headed Egyptian god Thoth: much preferred books than boxing matches ( image from Pinterest, goddessgifts.com)

Now, maybe they made ibises different in the Pleistocene, but there wasn’t much of bookish, scholarly Thoth about Xenicibis xympithecus, our utterly peculiar and amazing Twilight Beast. Roughly the size of a chicken, this extinct Jamaican ibis was unusual on two scores – it was one of only two known flightless ibis (the other one was in Hawaii…islands always have odd beasties), but it is the only bird known to have packed a punch, quite literally. For Xenicibis xympithecus had a unique wing structure which meant its wings were able to be used like a fist or a club.

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From Encyclopaedia Britannica, the chicken sized slugger itself, Xenicibis xympithecus

The first fossils of this strange fisted ibis were found in the 1919- 1920 excavations of the Long Mile Cave complex in Jamaica, but it was only in 1976, when the bones were re-examined, that suspicions were raised about just how very unusual this flightless bird actually was. Other examples of the critter started popping up in Jamaican and American antiquarian collections, such as those found at Swansea Cave, also in Jamaica. Moral of this story, and many others is that those mouldy old collections from Colonial times beg for fresh eyes and new techniques; after all, just look at the bear patella discovered loitering in the National Museum of Ireland last year!

There had been a bit of a theory put forward in 1982 that the punchy little bird had also been present in Cuba , but the flightlessness aspect put paid to that. Xenicibis xympithecu was a Jamaican creature through and through, evolved to fit in with island life. Islands do funny things to species; Darwin thought of insular evolutions as being living, breathing products of evolutionary ‘laboratories’, with creatures adjusting to fit perfectly into their environmental niches. He didn’t perhaps realise just how swiftly that process can move – recent research has shown that island species can undergo accelerated evolutionary changes sometimes within decades, but certainly within several thousand years , a blink of an eye in the sequences of life on earth.

When more fossil evidence was added to the strange case of X. xympithecus  during the 1970s and 80s, a better understanding of the bird was created. All birds, flightless or not, have ‘arm’ bones just like our arms, comprising of radius and ulna, except of course much lighter to allow usually for flight. Those bones lead to the carpometacarpus, basically the equivalent of the human fist. The structure around and behind these bones was formed to allow the bird to literally swing a hefty punch with its wing. Instead of being rudimentary little pretend wings, with lightweight bones, this ibis was sturdy, strong and heavier boned.

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Image from Longrich and Olsen 2011 showing the unique lower ‘wing’  ( labelled (h) ) of the Jamaican ibis

Some of their fossil bones actually have visible breaks in them, so it would appear these club-like wings were being used to thump something… but what? Could it be like the over-amorous killer swan of the Belfast hills who had to be deported to a sanctuary for delinquent ducks? Could the baseball-bat arms of X. xympithecus be used to slug out the best mate – survival of the species turned into Fight Club? It’s not unlikely, or at least were used as defence of some sort, but it may be more about territory than mating, as there really does not appear to be any sexual dimorphism in the bird bones. The Solitaire bird (also flightless, and also very extinct) of Rodrigues Island in the Indian Ocean had developed a bony knob structure on its wings, which it used to hammer its love rivals and win not just the lady pigeons but the best nesting areas. Extant ibises have been observed holding each other’s beaks and flapping their wings at each other furiously when enraged and either protecting territory or their young, so the amazing Xenicibis was very likely to use those mitts as well.

Depending on which version you believe, the birds died out between 10,000 and 2200 years ago. Its demise may have been caused by an environmental tilt in favour of one of the island’s predators, such as the yellow boa snake, or the extinct little monkey species Xenothrix mcgregori, as its bones were also found in situ at Long Mile Cave at the same excavation as our battling ibis. Nature is fragile –all it takes is a wobble in climate, a lurch of environmental change, and non-adaptive species vanish forever. Jamaica, like the entire Caribbean, has experienced climate shifts linked to changing tides and air currents as well as sea level changes throughout the Pleistocene and Quaternary periods. It also may not be surprising to know that Jamaica was only settled 2500 years ago by the Arawak peoples, who were migrating across the Antilles at that time.  Draw your own conclusions if you choose the more recent terminal date for Xenicibis.

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Long Mile Cave, Jamaica. image from cockpitcountry.com

So, there you have them – the amazing, strange and sadly extinct ibises with hurley-sticks for arms, who probably fought for territory and lurve with the same gusto. Some ibises round the Nile perhaps remember Thoth and his scholarly demeanour, as they glide on cloud-white wings among the hibiscus and palms of southern Egypt. But some, perhaps, remember when they were warriors. Birds, after all, have little dollops of dinosaur deep within their genes, and I like to think they remember that past, in a similar way to Mr Prosser in Hitch-Hikers’ Guide to the Galaxy , who remembered his bloodline to Genghis Khan at inopportune moments! We will never know if humans ever did witness the battles of the ibises amidst tropical rain forests, or seaside coves. But I’ll bet one thing – if they did, it must’ve been  quite a sight to behold the battle of the birds!.

Written by Rena Maguire (@JustRena)

Further reading:

Donovan, S.K. and Paul, C.R., 2011. ‘A diverse terrestrial fauna in the Pleistocene of Jamaica: the treasures of the Red Hills Road Cave’. Geology Today. 27.5  pp.173-180. [Full Article]

Donovan, S.K., Baalbergen, E., Ouwendijk, M., Paul, C.R. and van denHoek Ostende, L.W., 2013. ‘Review and prospectus of the Late Pleistocene fauna of the Red Hills Road Cave, Jamaica’. Cave and Karst Science. 40.  pp.79-86. [Full article]

Longrich, N.R. and Olson, S.L., 2011. ‘The bizarre wing of the Jamaican flightless ibis Xenicibis xympithecus: a unique vertebrate adaptation’. Proceedings of the Royal Society of London B: Biological Sciences. [Full article]

McFarlane, D. A., Lundberg, J., and Fincham, A. G. 2002. ‘A late Quaternary paleoecological record from caves of southern Jamaica, West Indies’. Journal of Cave and Karst Studies 64.2. pp 117-125. [Full article]

Millien, V., 2006. ‘Morphological evolution is accelerated among island mammals’. PLoS biology. 4.10. [Full article]

Morgan, G.S., 1993. ‘Quaternary land vertebrates of Jamaica’. Geological Society of America Memoirs. 182.  pp.417-442. [Abstract only]

Olson, S. L. and D. W. Steadman. 1977. ‘A new genus of flightless ibis (Threskiornithidae) and other fossil birds from cave deposits in Jamaica’. Proceedings of the Biological Society of Washington  90. pp 447–457.

Olson, S. L. and D. W. Steadman. 1979. ‘The humerus of Xenicibis, the extinct flightless ibis of Jamaica’. Proceedings of the Biological Society of Washington. 92 pp 23–27.

Olson, S. L. and A. Wetmore. 1976. Preliminary diagnoses of two extraordinary new genera of birds from Pleistocene deposits in the Hawaiian Islands. Proceedings of the Biological Society of Washington. 89. pp 247–258.

Scudder, S., 1991. ‘Early Arawak subsistence strategies on the south coast of Jamaica’. Proceedings of the Thirteenth International Congress for Caribbean Archaeology, Reports of the Archaeological-Anthropological Institute of the Netherlands Antilles .9.  pp. 297-315

Steel, L and Hume,J . 2013. ‘Fight club: a unique weapon in the wing of the solitaire, Pezophaps solitaria (Aves: Columbidae), an extinct flightless bird from Rodrigues, Mascarene Islands’. Biological Journal of the Linnean Society 110.1. pp 32–44. [Full article]

Suarez, W.  2001. ‘Deletion of the flightless ibis Xenicibis from the fossil record of Cuba. Caribbean Journal of Science. 37.1/2  pp.109-109. [Full article]

Posted in Ibis | Tagged , , , , , , , , , , | 3 Comments

Horned Armadillos and Rafting Monkeys

Walking back along the sandy path I could feel the refreshing cool air on my bare shoulders. The sun was starting to make its way down the horizon, turning the sky to fire. Rustling in the branches in the overhanging trees makes me stop. A little tuff-eared marmoset monkey sits confidently watching me. Then I spot another. More rustling and another appears. This well trodden sand path is the only way to one of the most beautiful beaches on Ilha Grande. These monkeys know it. Apple cores, biscuit remains and other food debris are evidence of countless tourists feeding these cute looking miniature monkeys. Suddenly, they scarper: as fast as they came, they vanish. A deep low growl rumbles in the trees behind. I knew there were jaguars in Brazil, but I hadn’t heard that jaguars had made it to the island. I wasn’t going to wait around to find out.

A gorgeous little Brazillian Common marmoset monkey. (

A gorgeous little Brazilian Common marmoset monkey. (Photo by Carmen Busko. Public Domain)

Brazil, and South America in general, has truly incredible wildlife. From Darwin’s Rhea to the wonderfully fun tapirs, this is a haven of wonderful creatures. It has an incredibly rich and unique fauna which has lived there over the last 65 million years. Why was it so special? What the heck is litoptern or a sabre toothed metatherian? To answer these questions, and more about the ancient mammals of South America, I was lucky enough to be offered a chance to review Horned Armadillos and Rafting Monkeys.

Such a concise, detailed book could only have been written by Darin Croft, at Case Western Reserve University. An expert in fossil mammals from South America, this is Croft’s magnum opus on his life’s passion. He wanted to put this book together to show off the incredible and weird animals that used to live there, most of which, he notes, people have never heard of.

South America is unique. Until about 3 million years ago, it was alone, drifting. After the break up of the mega-continent, Gondwana, the South American landmass split off from Antarctica. And here, for around 30 million years, it floated. Animals were pretty much isolated from the rest of the world, and evolved into their own unique forms. Croft takes the reader to meet these distinctive beasts from the very beginning of the Paleocene all the way up to the Quaternary.

The two major landmasses Laurasia in the north, and Gondwana in the South, around 200 years ago. (Image from here.)

The two major landmasses Laurasia in the north, and Gondwana in the South, around 200 million years ago. (Image Public Domain.)

Honestly, I wasn’t too sure when I first flicked through and saw the layout. First impression was that it looked like another textbook. As we all know, first impressions can be deceiving. As I began to read it, the layout made sense. It worked for the story Croft was crafting: the mammals that lived in South America over time.

Each chapter focuses on one palaeontology site looking at some of the key fossils found there. Each site is a unique piece used to create a detailed picture of the diverse animals in the past. From Bolivia to Argentina, we travel across the continent where digging the dirt allows us to read the pages in geological time. Something struck me as I read: by talking about the context the fossils were found in we go right back to the very roots of how we know what we know, and how there is still so much to learn. I liked this a lot! Looking at fossil sites (with some wonderful photos) reminds us that discoveries, either by serendipity or well planned, funded palaeontology digs, are the result of a lot of hard work. This is where the unglamorous real work begins out in remote places with determined, dedicated teams of people meticulously looking through the sediment for fossils. Often they return empty handed, or at best, with a few fragmentary fossils; tantalising hints of what could be.

Each site is well introduced with their place in the story of South America. It is clearly written for a general audience and although jam packed full of facts, Croft is gentle on the jargon. If you are wanting a personal touch, a little something to bring the author alive, you won’t find it past the prologue. But that actually doesn’t matter too much. You will find yourself lost in the incredible creatures filling the pages of this book. From giant carnivorous armadillos to tiny weird horse-like litopterns, this is a feast for the palaeo-naturalist.

A horned armadillo (Peltephilus ferox) carefully scouts around the entrance to its burrow before embarking on a search for food. Illustration by Velizar Simeonovski and provided courtesy of Darin Croft and Indiana University Press.

A horned armadillo (Peltephilus ferox) carefully scouts around the entrance to its burrow before embarking on a search for food. (Illustration by Velizar Simeonovski and provided courtesy of Darin Croft and Indiana University Press.)

Key species found at each site are listed, with some nice information about what it was and what the environment was like. Lovely artwork by Velizar Simeonovski means there is a visual connection with the extinct beasts and not just an unreadable Latin name on the page. For me the real gem of this book is the photographs of the fossils of each creature written about. Like the fossil sites mentioned above, this brings it all back to how we know what we know, and the hard work of the palaeontologists.

There are dozens of incredible creatures highlighted in this book. Our giant swimming sloth makes an appearance, as do several other Twilight Beasts. With nearly 30 million years of isolation, South America really was a unique ecosystem. Armadillos and sloths evolved there, and it is later in the Pliocene and Pleistocene where we see their giant forms. There was a very familiar looking sabre toothed relative of the marsupials, Thylacosmilus atrox which superficially looked like a cat, but was not even slightly related (the sabre toothed metatherian I mentioned earlier).

Later towards the end of the Pliocene, around 3 million years ago, North America and South America are joined by the Isthmus of Panama. South America was alone no more. This connection had an enormous impact on the ecosystems: lots of animals from both continents were able to migrate to new ecosystems in what is known as the Great American Biotic Interchange (GABI).

Those South American animals that migrate north were not as successful as the northern species that moved south. The giant sloths and glyptodonts only made it into lower north America because the environment was much drier than they were used to. The newcomers to the south, however, thrived in the tropical environments. Tapirs, animals almost symbolic of the Amazon, originated in North America. Rabbits, pikas, bears, weasels, and deer (including the smallest deer species, the gorgeous Pudu) are all animals that made their way south, and adapted so well they are well and truly at home. The only northern Order which didnt survive until today were the Proboscidea, the Gompotheres that made it south became extinct around 10,000 years ago.

The Great American Interchange showing the creatures that moved to explore new lands.

The Great American Biotic Interchange showing the creatures that moved to explore new lands. The green animals were South American beasts that travelled north. The blue animals are North American beasts that moved south. (Image Public Domain)

It may be my geeky side coming out, but I enjoyed it. It has a lot of information, which can be pretty heavy going at times, but I know I will be going back to this book again and again. It also answered my ponderings about cats and monkeys. Cats too made it into South America after the Great American Biotic Interchange. Monkeys arrived in South America way before the cats arrived: between 37-40 million years ago, some African monkeys came adrift in the Atlantic ocean and landed in South America (this probably happened several times, with many rafting monkeys not surviving).

Hop into a time machine, and land around South America between 65 million years ago and today, and this book would be your guide.

Written by: Jan Freedman (@JanFreedman)

Further Reading:

Croft, D. A. (2017). ‘Horned armadillos and Rafting Monkeys: The fascinating fossil mammals of South America.’ Indiana University Press. [Book]

Read more about the wonderful Gomphotheres here.

Love the Giant Armadillo, find out more here.

Charles Darwin’s lost giant ground sloth – here.

More about the enormous giant ground sloth, Megatherium – here.

Did you know giant ground sloths dug burrows? Here you are.

The worlds smallest deer – here.

Posted in Giant Ground Sloth, Gompothere, Ground Sloth, Macrauchenia, Pudu, Thalassocnus | 2 Comments

Open your eyes and see beauty

“Open your eyes and see what you can with them before they close forever.”  Anthony Doerr, 2015.

She is beautiful: She is quite possibly the most beautiful thing in the room. I have travelled to America to see her, and she does not disappoint for the one day I get. I stand there looking at her from afar. She is subtle. She is slight. She does nothing to stand out. She is there but almost isn’t. She just is.

I watch as several people walk right past her: their eyes on something else. A quick glance to their left and they would see her. I will them to look left; with all my grey matter, I will them. I almost shout out ‘look at her!’ but then one person does turn: they look but they don’t see.

Often the most beautiful things are right in front of us, and we don’t see them. Maybe we don’t see because we are not looking for it. Or maybe we don’t see the beauty in front of us because our minds are often removed from it: the need to look for bigger things, the safety of seeing familiar things. Our heads are so often full of other, more mundane thoughts that we cannot focus. Ironically, to clear your head and notice the detail of what is really in front of you relaxes you more: other thoughts are gone, worries no longer there, your brain is taking in the colours, the patterns, the detail. And it feels wonderful.

I stood in that room, watching people walk by, and was quietly sad because less than a handful stopped to look at her. I would go and see her every day if that room wasn’t around 4000 miles away from where I sit now.

And her. Just standing there. Just looking so beautiful. I still remember all the detail: those big eyes, the curve of her body, the smoothness of her skin. She was the most beautiful creature I had ever seen.

I was so lucky to see her. Even so, she wasn’t really there. I missed her. By a mere 11,000 years.

The enormous Columbian Mammoth on display at La Brea, pulls the visitors away from other displays. Author for scale. (Image, authors own.)

The enormous Columbian Mammoth on display at La Brea, pulls the visitors away from other displays. Author for scale. (Image, authors own.)

La Brea Tar Pits Museum, in Los Angeles, is the last place you’d expect to see her. But then again, this is an incredibly rich site; home to over 650 different species of Late Pleistocene fauna. You are greeted by a cleverly lit, fully mounted skeleton of a Giant Ground Sloth, (Glossotherium harlani) that looks alive although it is just bones. The lights are low, giving a quiet, subdued ambience. As you walk into the first main room, to the left of there are displays flat against the wall, which at a glance look like some bones of some small creatures, lots of 1970s font, and a model of some deer. To the right, in the centre of the room, is where the big specimens are: the specimens people want to see, the sexy specimens, the specimens people gasp at: the Mastodon, the enormous camel (Camelops), the goliath Columbian Mammoth. Following this trail of breadcrumbs leads you straight out into the next room, of giant birds and Dire Wolves. Break away from the trail, however, and there are wonderful displays against the wall: teeth from the Imperial Mammoth, bones from the ancient Bison, and her, the beautiful dwarf pronghorn, Capromeryx minor.

A display you could just walk past. But take a moment to stop. And appreciate how amazing this creature was. (Photo by Jan Freedman)

A display you could just walk past. But take a moment to stop. And appreciate how amazing this creature was. (Photo by Jan Freedman)

I see how easy it is to walk past her. She just looks like a small deer. Nothing special. Nothing compared to the enormity of the Columbian Mammoth, or the terror of the sabre-tooth cat. That is of course, if you don’t look. Open your eyes and you will see not a little deer, but something much rarer. Something much more beautiful.

The dwarf pronghorn belongs to an almost vanished group, the Antilocapridae, where the only surviving species is the Pronghorn Antelope in North America. Superficially looking like antelopes, they were not. They are actually more closely related to the ancient group of Giraffes (another beautiful group which once held a huge array of magnificent species, but is now down to just a couple today). Just as in Giraffes, the horns on pronghorns are bone growths out of their head – unlike deer where the antlers are not true bone.

There were once over a dozen different pronghorn species leaping across the North American wilderness, with their long, elegant legs. One species would have been at home more in the forests than the open plains: our Dwarf Pronghorn. And she was a small species, the smallest species of pronghorn: perhaps reaching up to my hips at just 60cm tall at the shoulders.

The Dwarf Pronghorn was the smallest pronghorn species. (Image by Jan Freedman)

The Dwarf Pronghorn was the smallest pronghorn species. (Image by Jan Freedman)

Capromeryx minor was a relative late comer to the Pleistocene scene. Although the Genus Capromeryx evolved around 5 million years ago, our little friend arrives just 300,000 years ago. Fossil finds show the distribution was fairly restricted to southern North America, perhaps an indication of their preferred habitat: more wooded than open, like the tiny pudú. In almost 300,000 years, they got smaller and smaller.

When you look at the skeleton of this animal, you can see how stunning it is. Long, slender legs hint at quick bursts of speed in an attempt to escape from predators. (I like to imagine them leaping away instead of running.) They had very tough teeth, indicating eating tougher plants than just grasses alone. Like all pronghorns Capromeryx minor had horns on their head, four in total: two slightly larger ones at the back, and two smaller ones at the front. Because they are extinct, we know so little about their lives: It may be that the horns used by males for fighting each other, because the males were larger.

These gorgeous little animals almost made it through to today, with the last known fossils dating to around 11,000 years ago, at the end of the last major glaciation. We don’t know why they vanished. At the same time many other of the familiar beasts of the very Late Pleistocene were disappearing. Climate was warming, glaciers were melting, and humans were hunting. It is unlikely that humans hunted the dwarf pronghorn to extinction. But there could have been an indirect impact. Ecosystems are complex, subtle, but reliant interactions of food, temperature, water, animals and plants. At the end of the Pleistocene many of the large fauna were removed from the ecosystem, plants retreated and new ones took root, and temperatures changed fast. Our little beast couldn’t leap fast enough to keep up.

Life is incredible. It is so fragile, and yet can appear so robust. All of these animals that are not here today show us what the world was once like. It was, and still is, astonishing. It is not just the big, or the familiar which make our planet beautiful. Stop and look at it all: the fly on the windowsill, the bird in your back garden, the person sitting next to you. Life is beautiful. When you open your eyes, you can really see that beauty.

Written by Jan Freedman (@JanFreedman)

Further Reading:

David, E. (2007). Family Antilocapridae. In D. Prothero, S. Foss (eds). ‘The Evolution of Artiodactyls’. The Johns Hopkins University Press, Baltimore, Maryland. [Book]

Doerr, A. 2015. ‘All the light we cannot see.’ Fourth Estate, London. [Book]

Hernández Fernández, M. & Vbra, E. (2005). ‘A complete estimate of the phylogenetic relationships in Ruminantia: a date species-level supertree of extant ruminants’. Biological Reviews. 80:pp.269-302. [Full article]

Jimenéz-Hidalgo, E., O. Carranza-Castañeda, M. & Montellano-Ballesteros (2004). ‘A Pliocene record of Capromeryx (Mammalia: Antilocapridae) in Mexico’. Journal of Paleontology. 78(6): pp.1179-1186. [Abstract only]

Kurtén, B., & E. Anderson (1980). Pleistocene mammals of North America. Columbia University Press. New York. [Book]

Janis, C. & E. Manning. (1998). Antilocapridae. In: C. Janis, K. Scott, L Jacobs, (eds.), Evolution of Tertiary Mammals of North America, Vol. 1. Terrestrial carnivores, ungulates and ungulate-like mammals, Cambridge University Press, Cambridge, UK. [Book]

Martin, P. S. (2007), Twilight of the Mammoths. University of California Press. [Book]

McMenamin, M.A.S.; et al. (1982). “Amino acid geochemistry of fossil bones from the Rancho La Brea Asphalt Deposit, California”. Quaternary Research18 (2): 174–83. [Abstract only]

Morgan, J., & N. Morgan. (1995). A new species of Capromeryx (Mammalia: Artiodactyla) from the Taunton Local Fauna of Washington, and the correlation with other Blancan faunas of Washington and Idaho. Journal of Vertebrate Palaeontology. 15: pp.160-170. [Abstract only]

Murray, L. (2006). The smaller Artiodactyls: peccaries, oxen, deer, and pronghorns. Jefferson, G. and L. Lindsay (eds) In: Fossil Treasures of the Anza-Borrego Desert: the Last Seven Million Years. Sunbelt Publications, San Diego, California. [Book]

Stock, C., 1930. ‘Rancho La Brea. A record of Pleistocene life in California,’ Science Series. No 37. Natural History Museum of Los Angeles.

Posted in Columbian Mammoth, Dwarf pronghorn | Tagged , , , , , , , , , , , , , , , | 3 Comments

The most (and least) read blog posts of 2016

A huge thank you to all our readers for another wonderful year of Twilight Beasts! For some reason we didn’t receive our annual ‘summary of’ breakdown, so we shall pull it together for you!

Thank you for all your continued support and feedback on our blog post about these wonderful creatures of the past. Living in this virtual world, it is not that easy to show how much we appreciate your support with the blog. We hope that readers do get that from our tweets and our writing.

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So, the eagerly awaited ‘best of’ list is here. Here are the most read (and the least read) beast blog posts of 2016. Show them a little love, and delve in deeper to discover more!

Bottom 5 read blog posts:

  1. Down the rabbit hole. Small islands and giant dormice take centre stage in this post looking at the fragility of species.
  2. The ancients of the forest. Not all our blog posts are about giant mammals. Or lizards. Or insects. This one is about a giant tree from New Zealand!
  3. T’was the night before Christmas. I guess, in the words of Pierce Bronsan, Christmas only comes once a year. But you can find out all about how Reindeers once travelled in their thousands across Europe!
  4. Baby’s got quack. Well, Japan once had a pretty big Duck. And this blog post has a pretty great title too.
  5. A tiny Twilight Beast in a world of giants. The least read post of 2016.: this deserves a click if only for the cuteness. Discover how the smallest deer, the Pudu, survived the last Ice Age.
Intricately carved from fragile mammoth tusk, these two reindeer look as though they are swimming, although this may be due to the lack of depth of a mammoth tusk. (image from the British Museum)

This beautiful object was carved from fragile mammoth tusk. These two reindeer look as though they are swimming, although this may be due to the lack of depth of a mammoth tusk. (Image from the British Museum)

 

Our top 5 read blog posts of 2016:

  1. Going Underground. A spectacular insight in to the lives of Giant Ground Sloths: some species dug enormous burrows!!
  2. The bear from Clare – new evidence for an early human presence in Late Pleistocene Ireland. Early last year a bear knee cap was discovered in the National Museum Ireland, with cut marks on it. Discover how this incredible find pushes back the date for humans in Ireland.
  3. Lost as the Moa is lost! The enormous flightless bird from New Zealand, the Moa, only became extinct around 600 years ago.
  4. On the Origins of our species. Our first guest blog post makes it in the tope 5! Find out where we come from, and how really, despite geography, we are all more closely related than we think.
  5. The hyena that was overshadowed by a Tyrannosaurus rex. Yay! A hyena post made it in the top 5!! This is all about the only hyena species that made it to America, he who saw the canon.
One enormous claw from a Giant Ground Sloth on display at North Carolina Museum of Natural Sciences. This enormous claw could dig through rock. To make tunnels!

One enormous claw from a Giant Ground Sloth on display at North Carolina Museum of Natural Sciences. This enormous claw could dig through rock. To make tunnels! (Image by Jan Freedman)

We hope you enjoyed our blog posts from 2016! We shall be bringing lots more new and exciting beasts to you for 2017.

Until then, enjoy the top (and bottom) 5 posts.

We wish all our readers a very happy and healthy 2017. Ross (@DeepFriedDNA), Rena (@JustRena) and Jan (@JanFreedman)

Posted in Brown Bear, Celebrate!, Giant Ground Sloth, Giant Maltese Dormice, Homo sapiens, Hyena, Kauri tree, moa, Pudu, Reindeer | Tagged , , , , , , , , , | 1 Comment

The Lost Sheep

I don’t know about you, but I love the spirit of farmers during lambing season. Coming from a farming background, I know the farmers’ mingled emotions of dread and hope and joy as the wee lambs are born often in the dead of winter. The late nights, camaraderie, the dance of life and death, sometimes played out against mountain snow; this time connects us with the farmers of prehistory. It is, above all, a time of hope when lambs are like tiny fuzzy reminders of springtime ahead and the renewal of life. I’m pretty sure even our pre-Neolithic ancestors gazed in admiration at the tiny, resilient animals frisking amidst the herds which passed through European refugia.

For this Twilight Beast, Megalovis latifrons, the giant sheep, we shall go back a little earlier than usual for this blog. Right to the very beginning, on the boundary of the Pliocene and Pleistocene. It was all happening during the Epivillefranchian period, that junction between the Pliocene and the earliest Pleistocene, about a 2. 6 million years ago. It’s believed there were numerous and regular large tectonic events, setting off a chain reaction of natural changes to the planet. Around this time, some species of hominins had made their way to Eurasia, and were also settling across Europe, though would get driven back by the gradual onset of glaciation through the Pleistocene. In Europe and Asia, there were numerous ‘dispersal’ events, occurring over a relatively short period of time, when whole faunal assemblages were replaced, and new critters arrived from other continents – elephants, horses and the rather charmingly named ‘Wolf  event’ of around 1.7 million years ago. Climate shifts were noticeable from the stable isotope analysis we have gained from ice cores. It was getting cold. Snow would fall, deep, and crisp and even….a dangerous time for sheep, a time when they can get lost.

The giant sheep

The giant sheep Megalovis latifrons, with our Rey for scale. This was an extremely large sheep.

There were only desperate hunter gatherers inhabiting Europe and Eurasia at this time, clinging to existence daily, battling everything the climate or lack of game could throw at them, so no shepherds watched flocks by night, or day– the Neolithic was quite a way yet!  This lack of attendance was probably quite welcome, or at least did not bother the giant sheep, Megalovis latifrons. There are very few fossil assemblages of this creature, although it is believed to have been around the size of a modern musk ox, with large, straight horns facing outwards like a sheep, and with similar dentition as well. There are some very early faunal assemblages from Verchets in Romania, indicating that Megalovis pre-dated the shift into the cold of the Epivillefranchian, and a substantial bone assemblage in Trlica, Montenegro dating right up to the early Pleistocene around 950,000years ago.

 

Horns of subspecies Megalovis balcanicus from CRÉGUT-BONNOURE and DIMITRIJEVIĆ 2006, reference in blog bibliography

Horns of subspecies Megalovis balcanicus (from CRÉGUT-BONNOURE and DIMITRIJEVIĆ 2006, reference in Further Reading)

This was the sort of sheep which could have delivered a bit of a lamb chop if it was provoked. It was a powerful and steady grazer of grassy open lands, but nimble enough to navigate the mountain ridges of Europe and Eurasia. We are not even terribly sure what they looked like, but we know from especially the Trlica assemblages they had pointy premaxillar bones on their jaws, which have been considered indications that they were fussy feeders, grazing on one single type of food, probably leaf-based. As folivorous creatures, chewing down cellulose-heavy leaves, they may have had slower metabolisms than modern sheep or goats. There’s been such a lack of understanding of this rare breed that palaeo folks weren’t exactly sure how to categorise them for quite some time – Sheep? Goat? Antelope? There is still sporadic new work on variations of giddy goats and sheep which may, or may not, be related to Megalovis.  There have been other branches of Megalovis identified, such as Makapania sp, which lived in Africa, although they may have been much more antelope-like than their European cousins.

We now have a pretty good idea that Megalovis was one of 19 species of Ovibovini, much closer to modern musk oxen and gorals than sheep as we understand them. The giant sheep was, to all appearances, a successful Pliocene species, yet by the middle of the Pleistocene, they were all extinct, which probably accounts for why there are no images of them (to date anyway) incorporated into cave art displays. And they must have been quite a sight, herds of extremely large sheep wandering the chilly grasslands of Europe. Until a complete assemblage is discovered, we still need to use guesswork about how they looked – though they probably resembled the extant goral – only larger.

A modern day Goral. (Image by FunkMonk on Wiki)

A modern day Goral. (Image by FunkMonk on Wiki)

So, if humans didn’t get the chance to over hunt Megalovis, what took the great sheep from the gene pool? As we mentioned earlier, the creatures were picky eaters (and feel free to use this cautionary tale on kids not eating their Brussels sprouts this Christmas!!). As vegetation changed with the creeping cold of the Pleistocene, the woolly jumpers just didn’t have enough to eat. Sadly, one of the perils of being a niche feeder is potential extinction should anything endanger the food supply. Gradually, they faded from the landscape, replaced by the less fussy Soergelia elisabethae and Praeovibos priscus. It would be the middle of the Pleistocene before species which we would well recognise today such as the ibex, would become the inheritors of the gap left by Megalovis.

We can only imagine how adorable the little lambs of the species must have been, and it is regretful that there are no known images of the creatures, compared to depictions of ibex, bison, mammoths and lions, which grace the walls of caverns across Europe, with their observations on nature and hunting, daubed skilfully by torchlight with charcoals and faith to express beliefs long since forgotten. If anything, our blogs echo the love of these animals from the deep past, our paintings made with pixels and words, communicating the same wonder as ancient peoples at this beautiful, amazing planet we live on.

One recurring theme of our blogs is how all species –ourselves included – are woven together in the warp and weft of climate and environmental change. Sometimes natural changes occur without human intervention, causing extinctions like Megalovis, replacing these creatures with more versatile species which can survive adverse conditions better. But life does go on… the miracle of adaption, rebirth and survival continues, just like modern little lambs at the worst time of the year may as well say ‘come at me bruh’ to wind and rain and snow. This Christmas, Hannukah, Kwanzai, or Yule (or simply winter break) we at Twilight Beasts wish you tenacity,  hope, courage and joy in these changing and often scary times.

And please – don’t be picky eaters – we want to share more amazing creatures with you during 2017!

From the Beast team of Jan, Ross and Rena – we wish ewe a wonderful season!

Written by Rena Maguire (@JustRena)

Further reading:

Bechev, D. and Georgiev, D., Paleobiodiversity of the Vrachanska Planina Mountains in the Villafranchian: a case study of the Varshets (Dolno Ozirovo) Early Pleistocene locality of fossil fauna and flora. [Full article]

Brugal, J.P. and Croitor, R., 2007. Evolution, ecology and biochronology of herbivore associations in Europe during the last 3 million years. Quaternaire. Revue de l’Association française pour l’étude du Quaternaire, 18. 2.  pp.129-152.

Cregut-Bonnoure, E, 2004. European Caprinae ( Ovibovini, Caprini) from the Plio-Pleistocene Boundary: a new interpretation. 18th International Senckenberg Conference Proceedings. [Full article]

Cregut-Bonnoure, E. and Dimitrijevic, V., 2006. Megalovis balcanicus sp. nov. and Soergelia intermedia sp. nov.(Mammalia, Bovidae, Caprinae), new Ovibovini from the Early Pleistocene of Europe. Revue de Paléobiologie. 25.2. p.723.

Gentry, A.W., 2000. An Ovibovine (Mammalia, Bovidae) from the Neogene of Stratzing, Austria. Annalen des Naturhistorischen Museums in Wien. Serie A für Mineralogie und Petrographie, Geologie und Paläontologie, Anthropologie und Prähistorie, pp.189-199. [Full article]

Gentry, A.W., 1970. Revised classification for Makapania broomi Wells and Cooke (Bovidae, Mammalia). Palaeontologia Africana. 13. [Full article]

Kahlke, R.D., García, N., Kostopoulos, D.S., Lacombat, F., Lister, A.M., Mazza, P.P., Spassov, N. and Titov, V.V., 2011. Western Palaearctic palaeoenvironmental conditions during the Early and early Middle Pleistocene inferred from large mammal communities, and implications for hominin dispersal in Europe. Quaternary Science Reviews. 30.11 pp.1368-1395.

Lehmann, U. 1953. Eine Villafranchiano-Fauna von der Erpfinger Hohle (Schwabische Alb). Neues Jahrbuch für Geologie und Paläontologie Monatshefte 10. pp 437-464

Lordkipanidze, D., Jashashvili, T., Vekua, A., Ponce de León, M.S., Zollikofer, C.P.E., Rightmire, G.P., Pontzer, H., Ferring, R., Oms, O., Tappen, M., Bukhsianidze, M., Agusti, J., Kahlke, R., Kiladze, G., Martinez-Navarro, B., Mouskhelishvili, A., Nioradze, and  M., Rook, L., 2007. Postcranial evidence from early Homo from Dmanisi, Georgia. Nature 449, pp 305-310.

Masini, F., Palombo, M.R. and Rozzi, R., 2013. A reappraisal of the early to middle pleistocene Italian bovidae. Quaternary International, 288, pp.45-62.

McClymont, E.L., Sosdian, S.M., Rosell-Melé, A. and Rosenthal, Y., 2013. Pleistocene sea-surface temperature evolution: Early cooling, delayed glacial intensification, and implications for the mid-Pleistocene climate transition. Earth-Science Reviews, 123, pp.173-193. Available at: http://dro.dur.ac.uk/10818/1/10818.pdf

Spassov, N. and Crégut-Bonnoure, É., 1999. First data on the Villafranchian Bovidae of Bulgaria. Comptes Rendus de l’Academie des Sciences Series IIA Earth and Planetary Science7. 328.   pp.493-498.

Turner, A., 1992. Large carnivores and earliest European hominids: changing determinants of resource availability during the Lower and Middle Pleistocene. Journal of Human Evolution22. 2.  pp.109-126.

Posted in Giant Sheep | Tagged , , , , , , | 1 Comment

Stuck in time

It is mid-November, and beads of sweat form on my forehead. Coalescence is inevitable. And it happens quickly; small beads merged into one humongous droplet, and it begins to meander its way down my nose, and there it dangles,  stubbornly defying gravity.

I am in Los Angeles, walking back in time. Although it is taking me a while to get there. Time travel isn’t quick. I walk out of my motel onto Crenshaw Boulevard, and start walking. On my map, the distance from motel to end point looks pretty short. It turns out I have chosen to walk along the longest road ever built by humans. The air is hot and dry. I feel the warm wind from the heat of the cars drafts against me as they drive past. The sidewalks are practically empty. No one, it appears, walks in Los Angeles.

An hour and fifteen minutes later, I am at the actual end of Crenshaw Boulevard (a street name that will stay with me always). I reach Wilshire Boulevard, one of the main arteries running east west across the city. Here, there is a different feel altogether. Where Crenshaw was lined with motels, fast food restaurants, and small, one story houses, Wilshire has large two story houses fronted by lawns and large drives, and there are tall, glass office buildings home to international businesses. My legs aching, I carry on. I am nearly there. Witshire has more people on the pavements. I pass smartly dressed business men and women darting in and out of doors on their mobiles. Women in Yoga pants appear to effortlessly float past, while the hipster beard makes an appearance more than once. I feel a little out of place, with my dusty, tired sandals, my chequered shirt clinging to my back, and myself looking a little like I have walked across a desert. But I am close. I am not here for the yoga pants. Or the hipster beards. I am here for the sabretooth cats. And the giant sloths.

On Witshire Boulevard, you can take a few paces away from the tall white, shiny, clean buildings, and step back in time. Here, in the middle of the 21st century hustle and bustle, you enter a different era: a time when giant American mastodons stomped. You have reached Rancho La Brea.

On teh busines

On Witshire Boulevard, a giant sabretooth cat welcomes you to the Tar Pits of Los Angeles. (Photo by author)

The Tar Pits at La Brea are world famous. Hundreds of thousands of fossils of Late Pleistocene animals and plants have been recovered at this one site. Animals and plants have become trapped in thick, sticky tar pits, and perished, showing us what life was like from around 50,000 years ago to just a few hundred years ago. What makes this site unique is the vast number of carnivores found here: around 70% of the fossil animals are carnivores. (Simply, an herbivore ended up trapped in the sticky tar, and was feasted upon by carnivores, which then themselves ended up getting stuck too.) It is the large carnivores that have captured the imagination of the media, like the enormous sabretooth cat Smilodon fatalis: which is in fact the state fossil for California. I have come here to find out more.

I meet with the Collections Manager at La Brea Tar Pits and Museum, Aisling Farrell. Her naturally warm welcoming smile and soft Irish accent immediately calms me, and removes any worries I had about being a tiny bit late. She laughs as I explain I walked here: “No one walks in LA!” she exclaims. I guess it is true then.

We walk outside of the George C. Page Museum, towards a fenced off area. Here there are life-sized models of mammoths and an American mastodon dramatically posed as if they were alive 20,000 years ago. I comment on the wonderfully elaborate models. Aisling looks at me, and smiles. “This is an old mine that has filled up with ground water,” she says turning back to look at the mammoth family. “The water table here is really high, so when it rains, this old mine traps a lot of water. It is nice, but it doesn’t show how the animals really got stuck in the tar.” I was about to probe a little more, when an enormous bubble of methane gas loudly came to the surface, and we spoke about the old mines.

One of the first sights a visitor sees,

One of the first sights a visitor sees, a mammoth stuck in ‘tar’ while  two family members watch helplessly.  (Photo by author)

Asphalt has been mined at Rancho La Brea for centuries. Although the site was privately owned in the mid-1800s, locals were allowed to mine asphalt for their own personal use (fuel, buildings, and roads). Bones were noted in the deposits, but they were thought to belong to domesticated animals, and it wasn’t until 1875 that the bones were recognised as fossils. The surveyor, developer, and highly respected citizen, Major Henry Hancock, acquired the land and began commercially mining the asphalt. Palaeontologist, William Denton, from Massachusetts, soon after visited the site and noticed sabretooth cat fossils, along with fossil deer and horse. Even so, it wasn’t until in early 1900 that palaeontologists seriously began studying the bones here.

Today, well over 3.5 million fossils have been recovered from the site. And over 600 species have been identified. This is an incredibly rich site.

With the sun beating down overhead, we walk across the grass. Aisling wants to show me something. We pass a few more small fenced off areas. “There are some spots here where the tar still reaches the surface,” she says, noticing my inquisitive look. “Even today small birds and animals do get stuck here.”

The grass is a vibrant green. A school group is being led by one of the several tour guides at La Brea. A young family is enjoying a picnic. The park is free for anyone to come and enjoy. “The land was left to the city by the Hancock family,” Aisling says as we make our way past a dog walker, with four dogs. “They owned a lot of land in LA. Unusually, they were also very interested in the fossils found here. They could have sold the land, but instead, left it to the people of Los Angeles to preserve the fossil site.”

Hidden amongst the

Hidden amongst the tall buildings, is a small spot of green. The park, left for the people by Hancock. (Photo by author)

We come to a small wooden building. Inside is a large window, overlooking a pile of dirt. Looking closer, it isn’t dirt, it is dried tar. And there are bones in it! Aisling is holding a bunch of keys as she spots the excitement on my face at seeing the bones exposed for the first time in millennia. She unlocks a door to the side, and we step through. We are leaning over the pit, on the other side of the glass. A curious father and daughter watches us from inside the wooden building. This is Pit 91, she explains. Fossils are being carefully excavated by staff and volunteers, and visitors to the park can watch them in action. The main deposit is not huge, just about three meters by two meters in the centre. The bones, darkened by the asphalt are easy to spot.

It might not look like much, but Pit 91 is revealing

It might not look like much, but Pit 91 is revealing new fossils during each excavation season. (Photo by author)

The commitment to the Page Museum to show the public the work that goes on here is inspirational. Large panels are scattered across the park, clearly and visually letting the visitors learn about the heritage of the site and the creatures that were once home here. In this park visitors are able to watch real palaeontologists excavate bones of extinct animals in front of them. I wondered how many children (and parents) watch these excavations and want to change their path to become a scientist.

Every single individual bone is carefully excavated and recorded. Today the information with each individual specimen is much more detailed than it was 100 years ago. Even the sediment is sampled for microfossils and some is sent off for pollen analysis providing more information about the climate and a detailed picture of the surrounding flora. Pit 91 has actually added over 320 new species to the fauna and flora of Rancho La Brea, including spiders, fish, amphibians, and insects. With new fossils being excavated daily, and the uncountable microfossils, a number of ‘three and a half million specimens’ at the museum is a very conservative estimate.

We talk about museum work, numbering, and the databasing, as Aisling leads us to one of the store rooms. Drawers upon drawers fill racks running the length of the store room. The sense of awe silences you as you walk in. Here, are thousands upon thousands of animals that lived not very long ago. You know you have stepped back in time. Passionately, Aisling talks about the animals that once lived here, while opening drawers: dire wolves, sabretooth cats, horses, camels, and more. So many creatures once walked on this very spot.

The author holding a bone from a dire wolf. You can see the extent of the drawers needed to store the collection. (Photo by Aisling Farrell)

The author holding a bone from a dire wolf. You can see the extent of the drawers needed to store the collection. (Photo by Aisling Farrell)

The skeletons on display in the museum are not from individuals, but composites: elements taken from several individuals and put together. I ask why it is not easy to find individuals in the excavations. “The general view of animals getting stuck and sinking into the tar is wrong,” she says. “An entire animal is rarely preserved. Think of it like fly paper. When a fly gets stuck on fly paper, the feet sink into the viscous stickiness. This is like how it was for the animals: the feet would get stuck. The body above the tar could have been eaten by predators, or even moved by the water, or weathered away. Anything below would be preserved. We rarely find full skeletons, perhaps because only a fraction of the animal got buried.”

I had always assumed the tar pits were a little like quick sand. Apparently this is a common misunderstanding. And it is why Aisling is not too fond of the flooded mine we saw earlier with the mammoth family. Fly paper. Not quicksand. The sticky tar seeps up from folded rocks deep below the surface. Some animals get trapped, and then sediment or water covers the tar. More tar seeps up, more animals get trapped, and more sediment covers it. It is often not as simple as that: sometimes the water can mix up bones and sediment.

The beautiful skeleton of a Monster Bird on display in the Page Museum. (Photo by author)

The beautiful skeleton of a Monster Bird (Teratornis merriami) on display in the Page Museum. (Photo by author)

The list of animals recovered from the site is spectacular. Along with reptiles, insects, fish and amphibians, are some glorious Late Pleistocene North American beasts: dire wolves, mastodons, mammoths, ground sloths, horses, camels, bison,  monster birds, short faced bears, American lions, and sabretooth cats (in fact two species of sabretooth cat: Smilodon fatalis and Homotherium serum). Aisling watches me as my eyes widen, and my voice goes slightly high pitched in the excitement of slowly pulling open each drawer. “Although there are lots of species, there is a bias with the fossils.” Carefully placing back a Smilodon fossil, I listen as she explains. It is also extremely likely that there will be gaps in time. “The tar is less sticky in cold weather. We see it here in winter.” Aisling never looses the passion in her voice, even as she talks about animals that are not here. The fossil deposits do not represent one continuous time period. There will be gaps. The gaps may be a couple of decades, or a couple of centuries long.

The incredible wall of around 400 dire wolf skulls on display in the Page Museum

The incredible wall of around 400 dire wolf skulls on display in the Page Museum. Author is shown for scale. (Photo taken by random museum visitor.)

The biggest project Aisling and her colleagues are working on at the minute, is to produce a detailed time line of the site. They want to use the large fossils along with the microfossils to discover how the environment has changed over this time, and how species responded to these changes.

It is an enormous project. Aisling, like her colleagues I met on my visit, know how big this is. They also know how important it is. If a detailed record going back 45,000 years can be created, it will show how animals and plants have adapted to environmental changes. And this can be used to see how animals and plants may respond to the dramatic climate changes happening now.

The gorgous sculpture of the American lion. (Photo by Author)

The gorgeous sculpture of two American lions juxtaposed with a skyscraper in the background.. (Photo by Author)

In the middle of Los Angeles is a world far away from the one we live in today. One without mobiles, or tablets. A world where the worries of modern life do not exist. A world where enormous lions stalked, and monster birds glided ahead. This was a world not that long ago. The fossils recovered from Rancho La Brea show us what an incredible landscape LA once was. What is truly magnificent is how visitors can see the work the staff and volunteers do to excavate, preserve and research the specimens. Today, over a hundred years after the first fossils were written about, Aisling and colleagues are still discovering new fact about the past, and using them to help protect our future.

Written by Jan Freedman (@JanFreedman)

An enormous thank you to Aisling Farrell, for sharing her endless enthusiasm and knowledge about the collections. Please do follow Aisling on Twitter (@AislingLaBrea)

To find out more about the Page Museum and La Brea, visit the website, or follow them on Twitter (@LaBreaTarPits)

My visit was made possible due to funding through the Jonathan Ruffer Curatorial Grants, overseen by the Arts Fund (UK).

Further Reading:

Campbell, K. E. & Tonni, E. P, (1983), ‘Size and locomotion in teratorns’, Auk.  100(2).pp.390-403. [Full article]

Feranec, R. S. (2004), ‘Isotopic evidence of saber-tooth development, growth rate, and diet from the adult canine of Smilodon fatalis from Rancho La Brea’, Palaeogeography, Palaeoclimatology, Palaeoecology, 206 (3-4), 303-10. [Full article]

Figueirido, B., J. A. Perez-Claros, V. Torregrosa, A. Martin-Serra, and P. Palmqvist. “Demythologizing Arctodus Simus, the ‘Short-Faced’ Long-Legged and Predaceous Bear That Never Was.” Journal of Vertebrate Paleontology 30, no. 1 (2010): 262-75.[Full Text]

Heintzman, P. D., G. D. Zazula, J. A. Cahill, A. V. Reyes, R. D. E. MacPhee, and B. Shapiro. “Genomic Data from Extinct North American Camelops Reveise Camel Evolutionary History.” Molecular Biology and Evolution in press (June 2 2015).[Abstract]

Howard, H, (1947), ‘A preliminary survey of trends in avian evolution from Pleistocene to recent time’, Condor. 49(1). pp.10-13. [Full article]

Martin, P. S. (2007), Twilight of the Mammoths. University of California Press. [Book]

Martin, L. D., and B. M. Gilbert. “An American Lion, Panthera Atrox, from Natural Trap Cave, North Central Wyoming.” Contribs. to Geology, Univ. Wyoming 16, no. 2 (1978): 95-101.[Abstract]

McMenamin, M.A.S.; et al. (1982). “Amino acid geochemistry of fossil bones from the Rancho La Brea Asphalt Deposit, California”. Quaternary Research18 (2): 174–83. [Abstract only]

Merriam, J. C., and C. Stock. The Felidae of Rancho La Brea. Carnegie Institute of Washington Publications, 1932.[Book]

Miller, L. H, (1909), ‘Teratornis, a new avian genus from Rancho La Brea’, University of California Publications, Bulletin of the Department of Geology. 5.  pp.305-317.

Stock, C., 1930. ‘Rancho La Brea. A record of Pleistocene life in California,’ Science Series. No 37. Natural History Museum of Los Angeles.

Tejada-Flores, A. E. and Shaw, C. A. (1984), ‘Tooth replacement and skull growth in Smilodon from Rancho la Brea’, Journal of Vertebrate Paleontology, 4 (1), 114-21. [Abstract only]

van Valkenburgh, B. and Hertel, F. (1993), ‘Tough Times at La Brea: Tooth Breakage in Large Carnivores of the Late Pleistocene’, Science, 261, 456-59. [Full article]

 

 

 

Posted in American Lion, Camelops, Horse, Mastodon, Sabre tooth Cat | Tagged , , , , , , , , , , , , , , , , , , , , , , , , | 3 Comments

Giant Sloths & Sabertooth Cats

Giant Sloths and Sabertooth Cats: Extinct Mammals and the Archaeology of the Ice Age Great Basin By Donald K Grayson

 

If there is one thing I enjoy doing in my downtime, it’s reading about Pleistocene megafauna. As well as having been my job, it’s also my hobby. No surprise I’ve been lucky enough to accumulate a nice stack of books on the subject. They’ve been useful for work, and also to break open when I need something good to read. My latest purchase is “Giant Sloths and Sabertooth Cats” (hereafter GS&SC) by DK Grayson, a name that should be familiar to anyone who follows the literature of the Pleistocene, and in particular the discussion of overkill. It was with great anticipation that I first cracked open the covers of this latest book. And I was not disappointed!

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GS&SC is that rare thing- a very academic book that is also by turns funny, forthright, interesting, and human. The author gives a lot of himself to his writing and comes through as a very likeable narrator. Dry humour abounds.

The book starts with a classic case that should be well-known to fans of the Pleistocene: the Nevada State Prison footprints. This acts as a great lede for the book as it brings in many of the themes that run throughout – dating of humans in the Americas, the weirdness of ground sloths, the variety of Pleistocene fauna. There are even some great vignettes of the level of feuding between 19th century palaeontologists (including the famed O.C.Marsh) and how preconceived notions can often lead researchers agley.

mylodontracks humantrackscope

There are chapters on the flora and fauna of the great basin to set the scene. The great basin is an area centred on Nevada but bleeding into Utah, Oregon, Idaho, and California depending on who you ask to define it. The great basin is a predominantly dry ecoregion surrounded by high mountain ranges that make up its flanks, and with a variety of topographical features from desert to mountain within. It is a very varied habitat home to some iconic plant species including Joshua tree (Yucca brevifolia), creosote bush (Larrea tridentata), and bristlecone pine (Pinus longaeva, one of the longest living trees on the planet, with some ancient individuals stretching halfway back to the Pleistocene). Of course the Pleistocene fauna is incredible. The bestiary chapter in the book is one of the best and most up-to-date I’ve read. Because its difficult to appreciate the Pleistocene fauna of North America, suffused as it is with sloths, glyptodonts, and other xenarthra, without reference to its Southern neighbour, Grayson has included a great section on the South American megafauna as well. The North American megafauna is treated comprehensively with sections on important species that includes distribution maps, evolutionary history, important fossil sites, charming reconstructions (by Wally Woolfenden) and the occasional photo of fossils or animals. The text accompanying the species descriptions is great and includes latest findings from ancient DNA, radiocarbon dating, stable isotopes, proteomics and other cutting edge stuff that has been filtered from the literature. As such it is a very timely and necessary update of the classic bestiaries from Kurten & Anderson’s “Pleistocene Mammals of North America” and Martin & Klein’s “Quaternary Extinctions”.

There are some great in-depth discussions included in the species biographies. For example, the incredible Manis mastodon find is brought up and both its dating and genetic implications covered. The Manis mastodon has a rib which incredibly also has a bone projectile (also made from mastodon bone) sticking into it, which must have been thrust in from above. Here Grayson lets slip his (perfectly respectable) bias with some special pleading that the Manis mastodon projectile could have been created by bone flaking due to intraspecific combat between mastodons in musth, rather than hunting by humans.

mastodon4

Varying views of the Manis mastodon (Mammut americanum) rib and bone projectile. From Waters et al.

mastodon_04

 

This bias against human explanations for the Pleistocene extinction appears as an undercurrent throughout some very useful chapters collating radiocarbon dates for megafaunal fossils, association (or lack of it) with contemporaneous humans and histories of important fossil sites in the great basin and the people who excavated them. These details are all fascinating and expertly explained, and include several TrowelBlazers (Bertha Pallan, Hildegarde Howard). In the final chapters the author lays bare his own thesis on what caused the megafaunal collapse in the great basin and all over the new world. Firstly though, he discusses the history of Clovis points (those wonderful and terrible sculptures of flint, that can take down elephants, and did take down mammoths and mastodons). There are sidetracks down issues of hyperdisease (interesting but difficult to find in the fossil record), the Younger Dryas comet impact (nonsense beloved of uber-cranks). Grayson has long been a proponent of a climatic explanation for the extinction of the megafauna. Here, he suggests that a species specific response to glacier loss and climate change best explains the staggered (over a couple thousand years) loss of the megafauna in the Americas. He argues that the relative lack of kill sites, the staggered nature of the extinctions, and the appearance of pre-Clovis humans in the Americas discount overkill as an explanation. I am obviously in the opposite camp and think that climate had little, or at most secondary effect in the extinctions.

What is interesting to me is that Grayson spends a lot of time in chapter 4 discussing how we can be misled by last appearance dates for species based on radiocarbon dates because we are unlikely to chance upon the last individuals of a species in the fossil record if they were common (like horse) and even less likely if they are rare (like Homotherium). When discussing the relative paucity and variety of kill sites, the same arguments must apply and I don’t think this is a strong argument against human responsibility because obviously we don’t expect there to be many of these sites (simply due to taphonomy) and the small window of overlap between megafauna and humans. Even given this, we are still left, in my opinion, with a clear signal of the immensely destructive and wasteful nature of human hunting in the audacious remains of Clovis points themselves. The thousands of points we have discovered were obviously crafted for one reason and one reason only. And it aint for hunting rabbits. These Kalashnikovs of the Palaeolithic speak more eloquently than a dozen butchery sites.

Now that we know that there were pre-Clovis cultures, does this impact on the likelihood of overkill? I don’t think so. All it suggests to me is that the culture evolved to meet different needs. Megafauna that have not encountered humans before are generally naïve (like Steller’s sea cow, or Galapagos tortoises) so the first immigrants into North America probably had no need for a specialised toolkit to hunt giant sloths or glyptodonts or mastodons that they could simply walk straight up to and butcher with a pointed bone stick right where they stood. Later, either as numbers diminished or naivety was eroded, the Clovis point could have given hunters the edge.

More thought must be given to the criticism that the staggered nature of the extinctions and the disproportionate loss of large mammals does not fit with human overkill. I think we can apply Grayson’s own arguments about radiocarbon dates and final appearances to the question of a staggered extinction. As more data comes in we are likely to find a less staggered sequence. Of course not all species went extinct at the exact same moment. The unique nature of each lost species means that it would have dealt with hunting pressure in different ways. But, geologically speaking, whether the extinctions happened over a couple hundred or several thousand years, the event would count as instantaneous to any observer from the far future. I even think overkill can provide a prediction that other explanations couldn’t in this scenario. If the extinctions are truly staggered (and we would need many more C14 dates to assess this) then it should likely follow a clear pattern, with the larger species succumbing before the (relatively) smaller species. If we were to find a pattern where common smaller species were going extinct before common larger species then that would argue against hunting as a cause. Or alternatively if we find last appearance dates (after sufficient sampling) that predate even pre-Clovis cultures then we can exclude humans as the causal factor. I don’t think we are going to find this.

Throughout the book Grayson does malign the overkill arguments as circular reasoning and in particular takes some pretty serious digs at Paul Martin’s abilities as a scientist (despite also praising his influence and providing some lovely compliments on his study of coevolution of fruits and megafauna). Martin was wrong in many of the things he said and wrote but a few of the comments do come across as petty given how much he did get right.

Overall, GS&SC is a must-have for any serious student of the Pleistocene. I disagree with Grayson on many of his conclusions but there is absolutely no doubting the depth and breadth of scholarship on display between the pages and he pulls off the incredibly difficult trick of making the text funny and warm. The book makes me think that the author would be an excellent person to share a couple of pints with in the pub while discussing our mutual love of Pleistocene mammals in a passionate but respectful manner. And if that isn’t a compliment I don’t know what is.

Small mistakes- Im only really qualified to pick up on the details of the carnivores but I noticed that the map of Homotherium finds omits the Tyson Spring Cave, MN find that was recently sampled for ancient DNA. There is also some confusion (table 4.4 in the book) about the difference between North American Panthera spelaea and Panthera atrox- a distinction which is well explained earlier in the book. Basically, the kind of tiny errors that are bound to be found in a massive undertaking like this book.

Written by Ross Barnett (@DeepFriedDNA)

Further Reading:

Waters, M. R., T. W. Stafford, Jr., H. G. McDonald, C. Gustafson, M. Rasmussen, E. Cappellini, J. V. Olsen, et al. “Pre-Clovis Mastodon Hunting 13,800 Years Ago at the Manis Site, Washington.” Science 334 (2011): 351-53.[Full Text]

 

Posted in American Lion, Antilocapra americana peninsularis, Bison, Brown Bear, Camelops, Cave Lion, Cheetah, Clovis hunters, Columbian Mammoth, Extinction, Giant Beaver, Giant Ground Sloth, Glyptodon, Gompothere, Ground Sloth, Horse, Mastodon, Peccary, Pronghorn, Sabre tooth Cat, Short Faced Bear, Teratorns, Woolly Mammoth | Tagged , , , , | 2 Comments