Scientists Prepare to Set Camera Traps in Hunt for Thylacine

Ever since the last known Thylacine died in Hobart zoo back in 1936, there have been numerous “sightings” both in Tasmania and on the Australian mainland of this marsupial, frequently referred to as the “Tasmanian Tiger”.  Most of these reports have been dismissed either as hoaxes, or as observers mistaking foxes or feral dogs for the largest carnivorous marsupial known to have co-existed with modern man during the Holocene Epoch.

Grainy photographs and blurred film footage have come to prominence from time to time, helping to fuel the debate as to whether Thylacines (Thylacinus cynocephalus), which were believed to have been hunted to extinction, might just have survived, with a few scattered populations holding on.

A Stuffed Thylacine (Thylacinus cynocephalus) in a Museum

Stuffed Thylacine (Tasmanian tiger).  Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur.

To view the range of CollectA models: CollectA Age of Dinosaurs Popular Models.

Scientific Expedition to a Remote Location in Northern Queensland

A field team will be dispatched to the remote Cape York Peninsula (northern Queensland), in a bid to search for evidence of the existence of a surviving Thylacine population.  The team, led by Professor Bill Laurance of James Cook University (Queensland), hope to set fifty camera traps in the area so that photographic proof can be established.  The Cape York Peninsula has been chosen as a number of credible witness accounts of possible sightings, including one from a tourism operator and former park ranger, have occurred in the locality.

Professor Laurance commented:

“All observations of putative Thylacines to date have been at night, and in one case four animals were observed at close range, about 20 feet away, with a spotlight.  We have cross-checked the descriptions we received of eye shine colour, body size and shape, animal behaviour, and other attributes, and these are inconsistent with known attributes of other large-bodied species in north Queensland such as dingoes, wild dogs or feral pigs.”

The exact destination of the field team is being kept a closely guarded secret.  Nearly four thousand reported sightings have been recorded on the Australian mainland, it is the reports from qualified rangers, Aboriginal communities and the many credible witnesses that offer the tantalising prospect of a live population being identified.

Ranger Patrick Shears, explained that local Aboriginals call the beast the “moonlight tiger” and that many observers claim that these marsupials approach quite close, before turning their long, stiff tails and trotting away into the darkness.

A Reward Offered for a Living Thylacine

Tasmanian tour operator Stuart Malcolm has offered an $1.75 million AUD (£1 million GBP), reward for proof that the Thylacine has survived to the present day.  Professor Laurance and his team are not interested in any reward money, after all, it was a bounty placed on each dead Thylacine recorded, that helped devastate the species in Tasmania.

The Professor is not particularly sanguine when it comes to the chances of the expedition being a success.  He has stated that it is very unlikely that the Thylacine has survived on the Australian mainland.   However, with a number of credible reports to guide them, it seems that if the Tasmanian Tiger has survived anywhere on the mainland of Australia, the Cape York Peninsula is a good place to start looking.

CollectA introduced a finely detailed model of a female Thylacine into their model range last year.  This model is quite hard to find, but not as difficult as a live Thylacine to track down.  Everything Dinosaur stocks this model, for the CollectA Thylacine and other rare CollectA models: CollectA Prehistoric Life Figures.

The CollectA Prehistoric Life Thylacine Model

The CollectA Thylacine model.

Everything Dinosaur intends to add a second Thylacine model to its already, extensive range later in the year.   Check this blog for more details about the model and also for updates on the Queensland expedition.

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Researchers Create “Trillennium Man”

Interactive three-dimensional models of human joints, showing how common medical complaints have arisen and how we are likely to evolve in the future, have been created at Oxford University.  The research was led by Dr Paul Monk (Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences) and it has led to the creation of a computer model of a human skeleton, one that represents a possible individual living around the year 6017 AD.  This individual has been nick-named “Trillennium Man”.

“Trillennium Man”

The Research Team Plotted the Evolution of Key Tetrapod Joints

“Trillennium Man” plotting the evolution of key joints in the human body.

Picture credit: Oxford University

Dr Monk was interested in exploring why patients at his clinic presented with very similar orthopaedic problems.

He explained:

“We see certain things very commonly in hospital clinics, pain in the shoulder with reaching overhead, pain in the front of the knee, arthritis of the hip, and in younger people we see some joints that have a tendency to pop out.  We wondered how on earth we have ended up with this bizarre arrangement of bones and joints that allows people to have these problems.  And it struck us that the way to answer that is to look backwards through evolution.”

Computerised Tomography Used to Assess Three Hundred Specimens

A total of 224 bone specimens were scanned (CT scans), in order to assess how the human body and joints such as the shoulder, hip and knee have evolved and changed over time.  Specimens from the Smithsonian Institute (Washington) and the London Natural History Museum were used in this study.

Tetrapods involved in the research included members of the hominin tribe such as Homo ergaster and Homo erectus as well as a range of other fossils, including some that represent some of the very first terrestrial vertebrates to have lived.  The scans were than mapped using a computer programme to produce three-dimensional images to show how the bones and joints had changed.  This research has provided new insights into the morphological trends with common orthopaedic complaints such as shoulder pain and anterior knee discomfort.

The Bones of Australopithecus afarensis were Incorporated into the Study

Fossil bones used in the study.

For replicas and models of ancient hominins: Wild Safari Prehistoric World Figures.

Considering Future Potential Human Joint Problems

By extrapolating the mathematical models, the research team could attempt to plot how our bodies and their key joints will evolve in the future.

Dr Monk added:

“Throughout our lineage we have been adapting the shape of our joints, which leads to a range of new challenges for orthopaedic surgeons.  Recently there has been an increase in common problems such as anterior knee pain, and shoulder pain when reaching overhead, which led us to look at how joints originally came to look and function the way they do.  These models will enable us to identify the root causes of many modern joint conditions, as well as enabling us to anticipate future problems that are likely to begin to appear based on lifestyle and genetic changes.”

Quadrupeds and Bipeds

Both quadrupeds and bipeds were included in the study, the research even involved examining how dinosaurs with their digitigrade and semi-digitigrade stance evolved and changed over time.

Commenting on the significance of this research, Dr Monk concluded:

“Current trends reveal that the modern shapes of joint replacements won’t work in the future, meaning that we will need to re-think our approach for many common surgeries.  We also wanted to see what we’re all going to look like in the future, and to answer questions such as ‘are we evolving to be taller and faster or weaker’, and ‘might we be evolving to need hip replacements earlier in the future?”

Human Hip Bones Evolving

As our distant ancestors adopted a bipedal method of locomotion so the femur (thigh bone) changed.  The neck became gradually thicker to help support body weight.  The thicker the neck of the bone in the femur the greater the likelihood of arthritis in the hip joint.  Orthopaedics have suggested that this thickened neck of the femur might be a reason why our species is prone to hip problems.

Over Millions of Years the “Neck” of the Femur has Become Thicker

Neck of the hominin thigh bone has become broader to support our weight.

Picture credit: Oxford University

In the picture above, the proximal end of a human femur (H. sapiens), has been modelled using the CT scans (right) and this is compared to the model produced from scans of an early hominin (left).  The red arrows indicate the region of the neck of the thigh bone that has become thicker.

Everything Dinosaur acknowledges the assistance of the University of Oxford press room in the compilation of this article.

The Everything Dinosaur website: Everything Dinosaur.

Cave Paintings Reveal Surprising Clues to Bovid Evolution

The cave paintings left by our ancestors can be very evocative.  The often elaborate and highly stylised frescoes represent life in the very distant past, a life so far removed from today.  However, the paintings, in most cases, a record of the animals that shared the environment with these hunter/gatherers, hide hidden clues regarding prehistoric animals that modern-day researchers are only just beginning to appreciate. Cave art has helped to confirm the exisitence of a newly described bison species, nicknamed the “Higgs Bison”.

Climate Change Affecting Large Animal Populations

A report published in the journal “Nature Communications” by scientists from the University of Adelaide, documents the study of DNA recovered from fossil bones in order to map how climate change affects large animals.  A surprise awaited the scientists, they have discovered a previously unknown species of bison, only to find out that this bovine was already recorded on the walls of caves across Europe, such as in the Niaux Cave (south-western France).  These cave paintings are dated to around 17,000 years ago (Late Upper Palaeolithic).

In 1999, the Australian-based research team commenced the study of DNA extracted from bison bones excavated from a number of sites located in the Northern Hemisphere, where the Steppe bison (Bison priscus) roamed.  The objective of the study was to assess the impact of changing global climate upon animal populations and in North America the fossil record for bison reflected the impact of a changing world.  Bison numbers crashed around the Last Glacial Maximum (between 18,000 and 21,000 years ago.)

Megafauna Extinction

Such data supports the idea that climate change played a significant role in the extinction of “megafauna”.

The scientists then expanded the boundaries of their research by examining data from South America, this also revealed that rapid warming events were a significant factor in large animal extinctions, often with species being further pushed towards extinction by the effect on animal populations by human hunters.

A Puzzle from Europe

When the focus of the research was directed at the fossil record and climate data from Europe, a rather puzzling picture emerged.  By studying mitochondrial DNA (which is inherited exclusively through the maternal line), recovered from fossilised remains, the team realised that the genetic signatures they were finding did not match those expected if the fossils had come from the Steppe bison (Bison priscus).  This was something of a puzzle as palaeontologists had thought that the Steppe bison was the only species to have been present in Europe before 10,000 years ago.

The European Bison (Bison bonasus)

The researchers realised that there were looking at the genes of something novel, an unknown species distantly related to modern cattle and to the exceptionally rare European bison (Bison bonasus), also called the Wisent.  The European bison is Europe’s largest, native, extant terrestrial mammal.  Once widespread, this bovine is now found in a few, remote and protected forests, particularly the Białowieża Forest between Belarus and Poland.

In a story, somewhat similar to the more famous Przewalski’s horse, the last wild Wisent was shot in 1927, but the species clung on thanks to a handful of animals kept in protected reserves.  Modern herds are descended from just a dozen individuals, including one bull from the Caucasus.

The European Bison Also Known as the Wisent (Bison bonasus)

The European bison.

Picture credit: Rafał Kowalczyk

To read about the conservation of Przewalski’s horse: Przewalski’s Horse – A Conservation Success Story.

For models and replicas of prehistoric animals including, whilst stocks last, Przewalski’s horse: Safari Ltd Prehistoric Animal Models and Figures.

The Elusive “Higgs Bison”

That famous Australian dry sense of humour came to the fore, when the DNA from the fossil bones proved to be neither Steppe bison or modern European bison, the team thought they had a new species but they could not be certain.  The elusive animal was nick-named “Higgs bison”, after all, the team had found evidence of something new, but they were not quite sure what this animal looked like, a parallel with physicists and their search for the Higgs boson particle.

In order to unravel this “Higgs bison” puzzle, the University of Adelaide research team set out to confirm their mitochondrial DNA results by obtaining nuclear DNA from the sixty-four European bison bones involved in the study.  Although, much harder to retrieve, nuclear DNA records all aspects of ancestry, not just the maternal line.  The small amount of nuclear DNA retrieved from the samples demonstrated that the “Higgs bison” was a hybrid, a cross between a female wild cow (extinct Aurochs) and a male Steppe bison.

The “Higgs Bison” and Hybridisation

The team dated this hybridisation event to more than 120,000 years ago.  This ancestry was the same for the Wisent and even though the mitochondrial DNA was different, a consequence of the recent near extinction event for the European bison, the “Higgs bison” was revealed as the ancestor of the Wisent.

Pressure on bovine populations as a result of rapid fluctuations in climate could have triggered the hybridisation process.

Male offspring of the Aurochs/Steppe bison cross were sterile, a common outcome for mammal hybrids.  As a result, several generations of females back-crossed with Steppe bison males (maybe even the same bull), resulting in a genetic ancestry of about 10 percent Aurochs and 90 percent Steppe bison.

Hybridisation Between Female Aurochs and Male Steppe Bison Leads to a New Species

Wisent evolution.

Picture credit: Nature Communications

Genetics and cave art reveal the assymmetric hybridisation between female Aurochs and male Steppe bison. Male hybrid offspring are sterile, and female offspring backbred with Steppe bison for several generations, possibly the same bull.

Looking for More Evidence – the North Sea and Cave Paintings

Having reached this conclusion, the Australian team then set about finding other sources of evidence to support the idea of a newly discovered species of prehistoric bison, resulting from the cross breeding between wild cattle and Bison priscus.  Two strands of supporting evidence were identified, both from surprising sources.

1. Scientists from Holland reported that amongst the many numerous Steppe bison and Aurochs bones dredged up by fisherman from the North Sea (for much of the Pleistocene Epoch sea levels were much lower and Scotland was joined to Denmark by a wide and extensive plain), bones of a less common, smaller bovine had been found.
2. French cave art researchers had identified two distinct forms of bison depicted in the artwork of our ancestors, one type resembled the hump-backed, massive Steppe bison, whilst the other depiction was of a more evenly shaped animal with reduced horns, much like a modern-day Wisent.

Depicted in Prehistoric Cave Art – the Newly Discovered Species of Bison

820 examples of bison depicted in European cave art are known, two distinct forms have been identified, representing two different species.

Picture: D. Viat/Tourismeoccitanie

Radiocarbon Dating of Cave Art

Radiocarbon dating of the artworks showed that the wedge-shaped form was drawn when Steppe bison were present on the landscape (around 18,000 years ago), while the small-horned version was drawn when the newly discovered species dominated Europe (after 17,000 years ago).  Each species appears to have dominated Europe for long periods of time, alternating in response to major climate changes.

Thanks to the accurate artwork of Stone Age people, scientists have a good understanding of what this new species of bison looked like.  It had been hiding in plain sight all along.

This study has thrown up a number of surprises.  Apparently, mammals can form new species by hybridisation, even if only rarely.  It also shows that despite the huge bison fossil record the depictions of these ancient creatures made many thousands of years ago, still have a lot to tell us about life in the past.

Everything acknowledges the help and support of “The Lead South Australia” in the compilation of this article.

The scientific paper: Soubrier, J. et al. Early cave art and ancient DNA record the origin of European bison. Nat. Commun. 7, 13158 doi: 10.1038/ncomms13158 (2016).

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The Evolution of Spiny Plants Holds Key to the Establishment of the Savannah

The continent of Africa contains a wide diversity of habitats, dominating the south, central part of Africa are the grasslands, the extensive savannahs that are home to a great diversity of iconic animals.  A team of international scientists writing in the academic journal “The Proceedings of the National Academy of Sciences United States”, have mapped the origins of the African savannah and concluded that the emergence of this ecosystem is, at least in part, down to the grazing habits of antelopes and their kin.

Ancient Bovids Influenced Habitat Formation in Africa

Honking to communicate in the hot savannah.

Picture credit: Todd Marshall

The picture above shows an illustration of Rusingoryx atopocranion a wildebeest from the Pleistocene Epoch.  Grazing bovids and antelopes may have had a remarkable impact on the evolution of plant communities.

Spiny Defences

In a study that plotted flora/faunal relationships on a continental scale, the researchers identified which mammal browsers are most closely associated with spiny communities of trees.  The team were able to show that over the last sixteen million years or so, plants from unrelated taxa developed spiny defences against being eaten a total of fifty-five times.  This pattern of convergent evolution suggests that the arrival and diversification of bovids in Africa changed the rules for persisting in woody communities.

Contrary to current understanding, this new data indicates that browsers predate fire by millions of years as agents driving the origin of the African savannah.

The study was conducted in an unorthodox manner.  The researchers, which included biologists from McGill University (Montreal, Quebec, Canada), started by observing fauna and flora relationships in Africa today and then working backwards in time to the middle of the Miocene Epoch.

For models and replicas of prehistoric mammals and other extinct creatures: Mojo Fun Prehistoric and Extinct Figures.

An Arms Race Between Plants and Animals

Many browsers like gazelles, delicately pick leaves off branches full of wicked-looking spines that are several centimetres long.  The scientists were able to uncover what happened in the past by mapping the distribution and evolution of the spiny plants on which gazelles and their relatives like to feed today.

Research team member, Jonathan Davies, (McGill University) commented:

“It’s been difficult to get a picture of how savannah ecosystems evolved because the conditions needed to preserve animal and plant fossils are very different from one another.  By working with the African Centre for DNA Bar-coding at the University of Johannesburg, we were able to sequence and compare DNA from nearly two thousand trees, and show that African plants only developed spines about fifteen million years ago. That was about the same time that a new type of mammal, antelope and their relatives, spread across the continent following the collision between the continental plates of Africa and Eurasia.”

Prior to this collision, the African continent had been dominated by the large, now extinct, ancestors of browsing elephants and hyrax.  These large herbivores would have bull-dozed trees and trampled vegetation, so spines were an ineffective defence against them according to the lead author of the study, Tristan Charles-Dominique (University of Cape Town).  However, antelopes and their relatives that arrived in Africa after the continental plate collision were highly efficient browsers, often using their delicate lips and prehensile tongue to remove leaves from branches.  It is likely that plants developed spines to defend themselves against these new plant “predators”.

Evolving a Spiny Defence Against Browsers

The study suggests a remarkable “arms race” between the trees and plant-eaters.  The arrival of new and efficient herbivores on the continent of Africa led to the evolution of more and more elaborate defences, including longer and longer spines.  One of the implications of this research is that the loss of large mammals like antelopes today, through human activities such as the bush meat trade, may have a substantial impact on the African landscape, with present day open savannahs being converted into thicket or brush.  Extensive forests may also make a comeback.

The Paper:  “Spiny Plants, Mammal Browsers and the Origin of the African Savannahs”.

Everything Dinosaur acknowledges the support of McGill University in the compilation of this article.

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