Did Dinosaurs Sleep with One Eye Open?

A new study into the sleeping patterns and behaviours of crocodiles suggests that these reptiles are able to sleep with one eye open.  The ability to sleep in this way probably evolved to help the animal’s stay vigilant and alert to danger.  This phenomenon is termed unihemispheric sleeping.  Half the brain rests whilst the other half, connected to the open eye remains alert.  Mammals such as dolphins can do this along with some birds and reptiles.

Did Dinosaurs Sleep with One Eye Open?

If crocodiles and some birds are capable of unihemispheric sleep, could the dinosaurs have slept in this manner?  Birds and crocodiles are the closest living relatives of dinosaurs, perhaps dinosaurs could sleep with one eye open?

Did Dinosaurs Sleep with One Eye Open?

A close-up view of the glossy eye of the Rebor hatching Baryonyx figure.  Did dinosaurs sleep with one eye open?

Picture credit: Jurassic Collectibles

Studying Extant Reptiles

Researchers from the Max Planck Institute for Ornithology (Germany) along with colleagues from La Trobe University (Australia) studied the sleep patterns and behaviours of Saltwater crocodiles.  These reptiles tended to sleep with both eyes closed but when another crocodile was introduced into their tank or a person approached, they kept one eye focused on the intruder.  Dinosaurs may have been vulnerable when they slept, as close relatives of the Dinosauria, demonstrate unihemispheric sleep, it is intriguing to consider whether dinosaurs slept with one eye open.

To view the large range of dinosaur themed toys and educational gifts available from Everything Dinosaur: Dinosaur Toys and Gifts.

Extension Ideas and Activities for Schools

• Question.  Why would some animals want to evolve the ability to keep alert whilst part of their body slept?

Answer.  When animal’s sleep they are vulnerable to attack, staying vigilant in this way can help to keep the animal’s safe.  In addition, some aquatic mammals are able to do this (dolphins etc.), they sleep with one eye open so that they can keep an eye on the rest of the pod.  It stops them becoming detached from their social group.

• Question.  In what other ways could sleeping animals keep themselves safe?

Answer.  They could hide, for example in burrows, they could climb trees to keep themselves safe (many birds roost in trees), they could live in a group such as a herd.   Whilst some herd members slept others could keep watch.

• Question, one aimed at more capable of learners tied in with KS3 studies.  If unihemispheric sleep is found in some mammals, birds and reptiles all vertebrates that are not that closely related to each other how did this come about?

Convergent Evolution

Answer.  This ability may have evolved in unrelated groups of animals independently, a case of convergent evolution, whereby similar characteristics evolve in unrelated animals as a result of having to adapt to similar environments or conditions.  Alternatively, this ability could have evolved long ago, in the shared, common ancestor of modern birds, mammals and crocodiles.

Ask the pupils to think about other examples of convergent evolution, for example bird wings and those of bats – similar characteristics but ones that have evolved independently in unrelated animals.

Everything Dinosaur team members work hard helping customers with their questions and queries, to view our testimonials: Everything Dinosaur Testimonials.

Eggshell Study suggests Dinosaurs Not Warm-blooded

Research published in the journal “Nature Communications” may have helped settle a 150-year-old debate amongst palaeontologists.  Analysis of the behaviour of two isotopes found in calcium carbonate, the main ingredient in eggshell suggests that dinosaurs were not warm-blooded (endotherms), neither were they cold-blooded (ectotherms) but they were somewhere in between.   The scientists conclude that dinosaurs were probably mesothermic, able to raise their internal body temperature above that of their immediate surroundings, but not all dinosaurs were able to maintain a body temperature at the level of today’s birds and mammals.

Dinosaur Eggshell Study

A dinosaur egg (believed to be from a theropod dinosaur).

Picture credit: Everything Dinosaur

A total of nineteen eggs from two different types of dinosaur were studied.  Eggshells from Argentina representing a Late Cretaceous, herbivorous titanosaur along with fossilised eggs from a theropod dinosaur (oviraptorid) from Mongolia were included in this ground-breaking research.  If scientists can determine the body temperature of extinct animals this will help them calculate metabolic rates and provide valuable data on how active these animals were.

Cold-blooded reptiles (ectotherms), like crocodiles are only capable of bursts of activity and rely on external sources of heat (the sun) to help them maintain a constant body temperature.  More active animals, (endotherms) like mammals and birds can generate internal heat and are generally a lot more active than their reptile counterparts.

An Example of a Typical Titanosaur

Perhaps up to 30 metres in length?

Picture credit: Everything Dinosaur

The picture (above) shows a sauropod model in the CollectA Age of Dinosaurs model range.

To view this range: CollectA Prehistoric Life Figures.

Dinosaur Eggshells

Commenting on the significance of this pioneering research, study co-author Aradhna Tripati (Assistant Professor of the University of California, Los Angeles) stated:

“This technique tells you about the internal body temperature of the female dinosaur when she was ovulating.  This presents the first direct measurements of dinosaur body temperatures.”

The research team conclude that clumping studies of two rare isotopes found in the eggshells show that oviraptorids (closely related to birds), were able to raise their body temperatures above that of their environment but not as high as warm-blooded animals (endotherms).  The much larger titanosaur had a body temperature slightly higher than our own.

This suggests that variable thermoregulation likely existed in the non-avian dinosaurs but not all dinosaurs had the body temperatures typical of modern birds and mammals which generally tend to be very active.

To read further articles on the dinosaur warm-blooded versus cold-blooded debate:

Clumped isotope analysis could determine endothermy: Isotope Analysis Could Help Shed Light on the Metabolism of the Dinosauria.

Warm-blooded or cold-blooded dinosaurs: Evidence to Support the warm-blooded or cold-blooded Debate in the Dinosauria.

Dinosaurs were endothermic: Endothermic Dinosaurs? The Debate Hots Up.

Ancient Horse Foetus Identified from Fossil Remains

Scientists from the Senckenberg Research Institute (Frankfurt, southern Germany), working in conjunction with colleagues from the University of Veterinary Medicine (Vienna, Austria) have identified the fossilised remains of a prehistoric horse foetus.  The 48-million-year-old fossil was excavated from the famous oil shales of Messel (near Frankfurt).

Fossil Discovery

The fossil was discovered fifteen years ago and set in resin to preserve it.  Using a combination of scanning electron microscopy and high powered X-rays, the scientists were able to identify the remains of an unborn foal within the adult animal.

The Fossil of the Ancient Horse (White Ellipse Marks the Site of the Foetus Fossil)

Scale bar 10 cm (A and B).  A line drawing and photograph of the Eurohippus foetus.

Picture credit: Senckenberg Research Institute

Eurohippus Foetus

This is the oldest equine foetus known.  The academic paper detailing this research has just been published in the scientific journal PLOS One.  It is widely believed that horses evolved from small, five-toed forest animals such as Propalaeotherium, fossils of which have been found in the Messel shales.  It seems that these ancient early horses thrived in the tropical forests of Europe that covered much of the Northern Hemisphere during the Eocene Epoch.

In this instance, the horse has been identified as an example of a genus called Eurohippus (Eurohippus. messelensis).  This is a remarkable fossil discovery.  An ancient mare preserved with her unborn foal.

For models and replicas of prehistoric animals including ancient horses: Wild Safari Prehistoric World Models.

Dinosaurs Inspire Handwriting

Following a dinosaur workshop with Lower Key Stage 1 children at a Nottinghamshire school, Everything Dinosaur’s fossil expert was asked to provide some extension ideas to help the teaching team keep the children motivated when it came to their writing.  Our expert suggested a number of activities and once back in the office, further supplementary resources and other support materials were emailed over to assist the teachers and the teaching assistants with their dinosaur themed term topic.

Dinosaurs Inspire Handwriting

Dinosaurs Inspire Handwriting

Dinosaur workshop thank you letter. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Thank You Letters

One of our suggested extension activities was to challenge the children to write us a thank you letter.  Could they include a statement in their letter telling us about their favourite part of the dinosaur workshop?  Could they use capitals and punctuation?  We received some really well crafted and well written thank you letters, a most impressive effort.  Well done to all.

Team members at Everything Dinosaur enjoyed reading all the thank you letters.  It was a case of dinosaurs inspire handwriting as a result of the dinosaur themed workshop at the school.

For further information about Everything Dinosaur’s work in schools: Email Everything Dinosaur.

To read testimonials from teachers, teaching assistants and members of the senior leadership team who have had visits from Everything Dinosaur to conduct fossil and dinosaur workshops or purchased items from Everything Dinosaur: Everything Dinosaur Testimonials.

All the Children in the Class Took Part in the Letter Writing Extension Activity

Pupils sent in thank you letters to Everything Dinosaur. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Everything Dinosaur

A spokesperson from Everything Dinosaur commented that team members liked to provide additional support to teachers and teaching assistants by proposing lots of extension activities after a dinosaur workshop.

Everything Dinosaur stocks a huge range of prehistoric animal and dinosaur themed toys and games. To visit Everything Dinosaur’s user-friendly and award-winning website: Visit Everything Dinosaur.

Homo naledi – New species of Hominin

A team of international scientists including researchers from the University of Witwatersrand (Evolutionary Studies Institute), South Africa have announced the discovery of a new species of human – Homo naledi.  The fossils, some 1,550 of them, have been collected from a cavern deep in a limestone cave system in the Cradle of Humankind UNESCO World Heritage site.  These fossils, the largest collection of hominin fossils found at a single location in the whole of Africa, will provide palaeoanthropologists with unprecedented levels of data.

Laying Out the Collection of Homo naledi Fossils

The most extensive hominin fossil find from Africa.

Picture credit: John Hawks/University of Wisconsin-Madison/University of Witwatersrand

Redefining What it Means to be Human

The bones were collected over a period of three weeks, following their initial discovery in 2013.  What puzzles the scientists is how did the bones get to be in the deep cave?  Bones and other debris can be washed in over time due to flooding, in this instance there is no evidence to suggest deposition of fossil material as a result of water transport.  Occasionally, such caverns are used as dens by carnivores, the bones of victims are preserved as evidence but there are no bite marks or evidence of scavenging on the bones.

Homo naledi

One theory is that these bones represent the dead bodies of individuals who were carried into the cave and deliberately placed there.  This suggests that Homo naledi was capable of abstract thought and, potentially, showing reference for the dead.

Co-author of the scientific paper published in “Elife”, Professor Lee Berger (University of Witwatersrand) stated:

“We are going to have to contemplate some very deep things about what it is to be human.  Have we been wrong all along about this kind of behaviour that we thought was unique to modern humans?”

To read a more in-depth article on Homo naledi: New Human Species from South Africa.

Dating the Fossils

Calculating the age of the fossils is proving difficult, but these bones could be up to three million years old.   Homo naledi had a brain about the size of a gorilla’s but a much smaller body, standing a little over a metre tall when fully grown.  Where it sits on the human evolution tree, very much depends on obtaining an accurate date for the fossil material.

Safari Ltd have produced a set entitled the “evolution of mankind” – a series of models that depict hominin evolution. To see the Safari Ltd model range: Wild Safari Prehistoric World.

Role Models in the Sciences – Go for it Girls!

One of the challenges faced by teaching teams is to encourage classes to adopt a more scientific approach to investigation and exploring the properties of materials.  The new national curriculum of England places great emphasis on working scientifically and with subject areas like adaptation, rocks, fossils and natural selection now part of the science element of this new scheme of work, teachers might struggle to identify suitable role models for the children.

An Early Role Model

Mary Anning (1799-1847), might be a strong candidate for consideration when thinking of historical figures that can inspire and enthuse girls, but there are a number of fantastically dedicated female scientists around today, extending our knowledge life on Earth and long-extinct animals.

Take for example, Canadian Victoria Arbour, whose work on ankylosaurs is helping to unravel some of the mysteries surrounding these armoured dinosaurs.  Victoria is happy to confess that she never grew out of her “dinosaur phase” and her career in palaeontology has taken her to some amazing places in a bid to excavate more fossilised bones.  Victoria is currently working as a postdoctoral researcher at the North Carolina Museum of Natural Sciences and North Carolina State University (USA).

Providing a Role Model for Girls as Well as Boys when it Comes to  Considering Science Careers

Victoria next to a skull of a Euoplocephalus tutus (University of Alberta).

Picture credit: Angelica Torices

Dr Arbour Comments

Commenting on her current role, Dr Arbour stated:

“Every day I walk past a Tyrannosaurus skeleton to get to my office, and my office is part of the exhibits at the museum, which means I get to see people enjoying that same Tyrannosaurus as much as I do.   In the summers I head out to the field to dig up dinosaurs in places like Utah, Alberta, and even sometimes Mongolia!  The rest of the time, I’m thinking about qnkylosaurs, the armoured dinosaurs with lots of spikes.”

It’s important for educationalists to recognise the wide range of science careers that are now available and the tremendous contribution being made to palaeontology and related fields by women.

An Illustration of a Typical Armoured Dinosaur (Ziapelta sanjuanensis)

New armoured dinosaur from New Mexico.

Picture credit: Sydney Mohr (Arbour et al. 2014, PLOS ONE:e108804).

Why the Ankylosauria?

Having undertaken her MSc and PhD degrees at the University of Alberta in Edmonton, a part of Canada with a wealth of Late Cretaceous dinosaur fossils to study, it’s not surprising that Victoria would find her academic career having a strong bias towards the Dinosauria, but why armoured dinosaurs (Ankylosauria)?  After all, ankylosaur remains are relatively rare in central and southern Alberta compared to other ornithischians – the duck-billed dinosaurs and the horned dinosaurs for example.

Victoria explained:

“I became particularly interested in them [armoured dinosaurs] when I started to think about what kind of project I wanted to do for my MSc thesis.  I kept seeing pictures in books of ankylosaurs using their tail clubs to defend themselves from predators and I wondered if there was a way we could figure out if they could have done that.  Some of the first projects I worked on looked at how fast and hard ankylosaurs could swing their tail into something and what would happen to the tail when they smashed into another object.”

Dr Arbour’s research has revealed lots of different aspects about armoured dinosaurs, from naming new species to learning about ankylosaur biology and potential behaviour, even looking at how these plant-eaters moved between continents.

A Role Model for Young People

For any young boys and girls considering a career in the Earth Sciences, researchers like Victoria provide an excellent example of what can be achieved.  It is important that teachers gain an appreciation of the growing number of female role models working in scientific disciplines.  There’s no need to worry about running out of dinosaurs to study, as Victoria is the first to admit, once you try to answer one question, new ones keep popping up and we still have so much more to learn about these amazing creatures that once roamed our planet.

To view the range of educational replicas of iconic fossil animals available from Everything Dinosaur: Replicas of Fossil Animals.

School Children Study Dinosaurs with a Literacy Focus

Pupils at Kingswood Primary Academy got to grips with dinosaurs and other prehistoric animals in a two-week long fossil themed summer school aimed at helping the children to improve their reading and writing skills.  The teaching experts at Everything Dinosaur were invited to take part helping to inspire and enthuse the pupils.  The ages of the children participating ranged from seven years to eleven years of age, the newspapers that they produced at the end of the fortnight which detailed their dinosaur discoveries were very professionally produced.

Dinosaur Summer School

The fossils and other objects that Everything Dinosaur brought to the school proved to be very effective teaching aids and the children loved “picking the brains” of our dinosaur experts and showing off their writing.  The fossil hunt organised for the second week of study was especially popular with the school children able to take home the fossils they had found.  The fossils were donated by Everything Dinosaur and come from various dig sites that the Cheshire based company had been involved in.  There were ammonites, sharks teeth, fossilised wood, pieces of fossilised bone, belemnite guards and even some super fossilised worm casts to discover.

We used a dinosaur soft toy from our wide range of prehistoric plush to teach about the properties of materials: Soft Toy Dinosaurs.

Feedback from the teaching team was extremely positive, comments received included:

“Very interactive, fascinating and relevant the children loved these activities”

Dinosaur Themed Summer School a Roaring Success!

5 stars for Everything Dinosaur.

Picture credit: Everything Dinosaur

Feedback Received

The picture above is a copy of the feedback form returned to Everything Dinosaur after the company’s participation in the summer school.  All too soon it was time to pack up but the team members did take time out to inspect some of the wonderful writing work that had been created by the children.  There were dinosaur posters, dinosaur fact cards, fact sheets all about extinction and even a marine reptile scene.

One of the teachers responsible for conducting the two-week long summer school stated:

“The Everything Dinosaur team member spent time with the children and answered all their questions.  Everything Dinosaur had a brilliant attitude with the children and they were really enthusiastic.  The team went out of their way to find extra information to answer one of the children’s questions.  Super resources.”

It seems that Everything Dinosaur’s work over the summer has been a roaring success.

To learn more about the company’s extensive product range: Everything Dinosaur.