Young Explorers Kit – Dinosaurs

Start Exploring Dinosaurs Activity Pack

Uncover some of the secrets about dinosaurs and other prehistoric animals with this fun-filled and educational “Explore Dinosaurs Activity Pack”.   This new Dinosaur themed kit contains lots and lots of activities, there is a giant Tyrannosaurus rex poster, the chance to design your own dinosaur stickers, make dinosaur trading cards and even the opportunity to come up with your own new species of prehistoric animal.

The kit comes in a handy box and contains everything required to complete the tasks, including paint brush, watercolour pencils, pencil sharpener and even an eraser (to help make your mistakes extinct).  This American designed set even comes complete with a 16 page palaeontologist’s handbook with lots of information and facts about dinosaurs.

The Start Exploring – Discover Dinosaurs Activity Kits

Picture Credit: Everything Dinosaur

In total there are 11 different posters featuring a variety of monsters from the Mesozoic, on test with our families and focus groups this kit has proved very popular.  Favourite items included the giant Tyrannosaurus rex poster to colour in – great for bedroom walls and the 3-D model of a meat-eater.  Art supplies are included in the kit, so it is a kind of self-contained activity centre of  young palaeontologists, there is even a little booklet that advises on different art techniques to try.  It is a great addition to the Everything Dinosaur toys and gifts range.

To see the kit and other craft items: Dinosaur Crafts for Kids

Frog Blog – Week 3 – Our Little Black Commas

Frog Blog – Week 3 – Little Black Commas

Our frog spawn in the office pond is approximately 2 weeks old and despite the very bad weather we have experienced in the last few days there are signs that things are beginning to happen.  The weather has been quite cold, although it is hard to say that it has been unseasonal, with the early Easter it is easy to forget that we are still in March and on the whole the winter has been relatively mild.

Only one warm sunny day over the last week, we have had heavy rain and blustery showers but fortunately not too many bonfires from the construction workers nearby polluting the water with ash drifting into the pond.  The water temperature remains cold but a close examination of the frog spawn shows that the little black dots we started with inside their protective jelly are beginning to change.  The majority of them are showing some definition, we have a lot of “little black commas”, the eggs are showing signs of development and we can see the start of a defined head end and a tail.

A Close up of the Frog Spawn

Picture Credit: Everything Dinosaur

Despite the cold weather the spawn is beginning to change, the picture shows that the embryos are developing, becoming more elongated and showing signs of progress.  We suspect that the water temperature will still be determining the rate of development, perhaps the warmer weather forecast for next week will help the spawn to hatch in the next 10 days or so.

Only one adult frog has been observed in the pond during office hours.  Ironically, it has taken to sitting next to the frog spawn using the surround pond week (Elodea) to support its weight.  We were a little concerned about this frog, normally frogs confine themselves to the margins of the pond, where there is more cover.  However, this frog, (we think it is a male), seemed quite happy to sit amongst the pond week in the centre of the pond.

Some of us started to speculate that this was the father, checking on his family to be, but this was probably a bit too fanciful for the more rational members of the team.  Amphibians do adopt many strategies when it comes to looking after and raising their young.  It is not just the so called higher forms of life, the mammals and birds that adopt a benevolent attitude to their offspring.

Demonstrating Dinosaurs Growing up Using Dinosaur Models

Juvenile Dracorex Dinosaurs

One of the rewarding things that team members at Everything Dinosaur can do is to use dinosaur models to show young dinosaur fans what we think juvenile dinosaurs looked like.  As dinosaurs grew so they changed, developing characteristics such as horns and crests that are associated with mature adult animals.  To illustrate this point, we choose to use our photoshop skills to modify an image of the Wild Safari Dinos Dracorex dinosaur model.  In this way, we could demonstrate ontogeny in prehistoric animals.

Dracorex – A Mature Individual with a Juvenile

Dinosaur models show

Dinosaur models show different growth stages (Wild Safari Dinosaurs)

Picture Credit: Everything Dinosaur

The adult in the foreground is larger, the scutes more pronounced and prominent.  The cheek colours are much brighter along with the yellow throat pouch, these are signs that this is mature adult ready to breed.  The much smaller juvenile lacks these features, the ornamentation on the head is very underdeveloped in comparison with the adult.  In this way, Dracorex dinosaur models can be used to illustrate aspects of the ontogeny of the Dinosauria.

To view Everything Dinosaur’s range of dinosaur models: Dinosaur and Prehistoric Animal Models

Estimating the Size of Smilodon (Sabre-Tooth Cats)

Estimating the Size of Sabre-Tooth Cats

With the Roland Emmerich directed film 10,000 B.C. proving popular with UK cinema audiences over the Easter holidays, staff at Everything Dinosaur have seen a resurgence in queries and questions related to prehistoric mammals.

Woolly mammoths and Sabre-Tooth cats tend to be the most popular of all the now extinct mega fauna of the Cenozoic, the fact that these animals play a prominent role in this new film will no doubt add to their popularity.  Certainly both animals are very enigmatic, although the size of these prehistoric beasts tends to be taken a little bit out of proportion by the Hollywood special effects teams.

Take the fearsome Sabre-Tooth cat for example, the best known and most researched species would be S. fatalis and the two sub-species from North America.  The superbly preserved remains removed from the La Brea tar pits have provided a huge amount of fossil evidence.  This fierce predator was not the largest of the Smilodon species.  Smilodon populator of South America, is believed to have been a little larger, perhaps exceeding 1.2 metres at the shoulder.

The impression re-produced below gives a rough idea of the scale of  the largest Smilodon species when compared against a human (not that we would recommend anyone attempting to get too close to one of these creatures)!

A Sketch Illustrating the Size of the large Smilodon (S. populator) compared to a Person

 

Picture Credit: Everything Dinosaur

The largest Smilodon would have been about the size of a male African lion (Panthero leo), but up to 300 kilogrammes in weight, making them much more heavy set than the largest of the big cats around today.

When it comes to the “top dogs” in the cat family the Panthero genus (lions) may have the last laugh, several extinct sub-species of Panthero leo may have been even larger than the biggest of the Smilodons.  It seems that those “big cats” such as S. populator, belonging to the sub-family of Machairodontinae, had some pretty strong competition from other members of the Felidae. Take for example the American lion (Panthero leo atrox), a contemporary of Smilodon fatalis, this fearsome beast is estimated to have been about the same height and weight of the largest of the Smilodons but less compact, perhaps reaching lengths in excess of 2.5 metres.

Although the American lion is known from the La Brea fossil deposits, relatively few remains have been found when compared to other carnivores such as the Dire wolves (C. dirus) and Smilodon fatalis. Perhaps the lack of fossils indicates that there were relatively fewer lions within the ecosystems that the fossil record represents, or maybe the American lion had a different hunting strategy and preferred habitat that took it away from La Brea.  Perhaps the American lion was just a little too smart to get caught in the tar pits.

Ironically the largest carnivore from the La Brea deposits is not a member of the Felidae at all.  The Short-faced bear (Arctodus simus), was the largest carnivorous animal around the area of La Brea towards the end of the Pleistocene.  A massive animal 1.5 metres high at the shoulder, capable of raising itself to a height of 3 metres or more and weighing perhaps as much as 800 kilogrammes, if a member of the Felidae stumbled across one of these bears, it would be better off getting out of its way.  The Short-faced bear is reputed to have been the largest bear to have ever existed.  Compared to modern brown bears its limbs were much longer and it had a short, broad muzzle (hence its name).  The jaws were extremely powerful and this animal would have had an awesome bite.

Little is known about the behaviour and habits of the Short-faced bear.  Chemical analysis of fossilised bones indicate a predominately carnivorous diet, but whether this bear was an active hunter of a scavenger is unknown.  It was certainly capable of chasing off both Smilodon fatalis and the American Lion in order to take over a recent kill.

Sabre-Tooth Cat Up Close

Capturing the Essence of a Sabre-Toothed Cat

Team members at Everything Dinosaur have tried to capture the essence of the Smilodon genus in a single picture.  It was obviously really, we had to focus on these huge upper canines that give these cats their name.  Remember these animals were not closely related to extant tigers.

A Close up of a Model of the Head of a Sabre-Toothed Cat

A Picture of a Sabre-Toothed Cat

Can't call it a Sabre-Toothed Tiger

Picture Credit: Everything Dinosaur

Slowly but surely Everything Dinosaur team members are getting more confident when it comes to using Photoshop CS5 and other tools.  It really was an excellent Smilodon model to practice our skills on.

Dinosaur Jawbone found on Bus in Peru

Dinosaur Jawbone found on Bus in Peru – Evidence of more Fossil Smuggling

Peruvian officials got a bit of a surprise when they opened a suspicious package that had been stored in the cargo compartment of a bus on route to Lima.  Inside the well wrapped parcel they discovered the fossilised jawbone of a large prehistoric herbivore.  The fossil is part of the lower jaw (left and right dentary) and it has been tentatively ascribed to belonging to a large Ceratopsian (horned dinosaur), although more work and analysis is needed to confirm the age of the fossil and to definitively place this unusual cargo within the Ornithischia.

An Unusual Find – the Prehistoric Jawbone

Picture Credit: Reuters

The picture shows a Peruvian police official displaying the fossil specimen at a news conference. The large grinding teeth can clearly be seen indicating a herbivorous diet but further study is required to identify the family to which this animal belonged to.

The fossil, which weighs 8.5 kilogrammes, was found in the cargo hold of the bus.  The bus was on route to the Peruvian capital Lima, the fossil was in an unmarked parcel that had been sent on the bus company’s package service.

“They began to check the package because it didn’t have anything to indicate what was inside. They were worried about its weight, opened it and found the fossil,” said Kleber Jimenez, a local police officer.

Peru has struggled for years to combat trafficking of fossils and artifacts. Recently Yale University in the United States agreed to return thousands of pieces taken from the ancient Inca citadel of Machu Picchu to Peru.  Raiding archaeological and palaeontological sites is quite common as locals try to make money out of the area’s prehistory.

“The jawbone that was found could be from a triceratops, even though dinosaurs like that have never been found in southern Peru,” Pablo de la Vera Cruz, an archaeologist at the National University in Arequipa in southern Peru.  However, this identification is only based on an examination of the police photographs, much more study is required before a more certain diagnosis can be made.

Ceratopsians such as Triceratops, Styracosaurus and Torosaurus are known from the northern hemisphere, the Cretaceous landscape of Laurasia.  Some fossil evidence has been produced to support the theory that horned dinosaurs existed in South America, on the super-continent of Gondwana, most notably the material associated with the Ceratopsian Notoceratops bonarelli but this remains controversial.  If Ceratopsian fossils are found in South America then this has implications for scientist’s understanding of plate tectonics, the movement of the continents and land masses over time.  It had been thought that the super-continent of Pangaea had begun to break up separating the southern continents from their northern counterparts long before the evolution of the Ceratopsians.  Fossils of horned dinosaurs found in South America would force geologists to reconsider the dating of the Pangaea break up.

If the fossil turns out to be Ceratopsian then this does not confirm the existence of such animals in Peru.  The fossil could have been excavated from the Western USA (the more usual home of these dinosaurs) and found its way to a collector in Peru.

For the moment, the fossil is residing in police custody, given the strict rules for exporting artifacts from countries, coupled with the allegations of smuggling, the sender of the parcel may be reluctant to come forward to claim it, so it will probably remain a bit of mystery as to how such an unusual specimen came to heading to Lima in the luggage hold of a bus.

Extract taken from a report by Miguel Zegarra and Marco Aquino

The jaw bone is certainly large and robust, indicating a substantial herbivorous animal.  Whether it is finally identified as Ceratopsian or even belonging to a member of the Dinosauria is uncertain.  After a more complete examination the fossil may turn out to be much younger than Cretaceous, perhaps belonging to one of the large Cenozoic marsupial or placental mammals known from the area.

To see a scale model of a Triceratops and other horned dinosaurs: Dinosaur Toys for Girls and Boys – Dinosaur Models

10,000 B.C. Movie Review

10,000 B. C. Movie Review

Director Roland Emmerich is well known for big, block buster type movies such as “Independence Day” and “The Day After Tomorrow” but on this occasion he takes the viewer back in time, in a bid to tell a tale from prehistory.

A fur adorned mountain tribe, happily living out their lives believing that the Woolly Mammoth herds are the centre of the universe, is raided by brutal warlords looking for slaves to help them build a temple to their God.  Our hero, a young hunter called D’Leh (played by American actor Steven Strait) sees his love Evolet (Camilla Belle) carried away and so he sets out to rescue her.

Along the way he encounters all manner of strange tribes, most of which have a grudge against the slave warlords as they too have been raided.  What starts off as one man’s quest to find his girl ends up being a sort of crusade against the tyranny of the evil warlord empire and their pyramid temples.  As D’Leh wanders through strange deserts and jungles in search of Evolet his small band of followers swells and grows to become an army – just what you need if you are going to have a final showdown with the bad guys.

If you put aside for one moment the historical inaccuracies, the absurd geography (we think much of the film was shot in Namibia as well as New Zealand so in essence our heroes were heading in the wrong direction), and the out of proportion prehistoric animals depicted, then this is a fairly pleasant way to spend an afternoon.  The story is not exactly subtle or complicated (unless you count the bizarre ancient prophesies) but as this film is aimed at a pre-teen audience then it hits all the right buttons.  Plenty of action, not a lot of dialogue or plot and some interesting special effects.  Any film with CGI Mammoths can’t be all that bad, and the 12A rating permits youngsters to watch (accompanied by an adult).  The narration got a little iritating at times, what was Omar Sharif thinking!

Absolute hokum, but if you have nothing better to do on a wet March afternoon…

Some points about the prehistoric animals – the Terror Birds (Phorusrhacidae) survived in South America until about 5,000 years ago but we are not sure what evidence there is for these large, flightless birds surviving in the Old World into the Pleistocene/Holocene (we think there is none).  The Sabre-Tooth Cat has been given the typical markings of an ambush killer and these animals although associated with the Americas (where the last Sabre-Tooths lived), they were more widespread in earlier times.   Our alledgedly Palaeolithic hunter might have encountered big cats, but it is highly unlikely that one of them would have been a Smilodon.  The Sabre-Tooth cat depicted in the film is truly huge, far larger than the Pleistocene Sabre-Tooths.  Most of the large Sabre-Tooth cats were about the size of a modern lion (P. leo) although much more stocky and heavy set.  The largest of the last Smilodon species was S. populator of South America.  It would have stood about 1.2 metres high at the shoulder.  We think the CGI operators have used a little bit of licence when it comes to the scale of some of these people.

It might be that the people depicted in the film are actually very small, this could be why some of these animals look so big.  If that is the case then this too is historically inaccurate, there is some evidence to suggest that Stone Age people were actually a fraction taller than their modern counterparts.

Mass Extinctions – Putting the “Big Five” into Perspective

Extinction Events are happening all the Time

The mass extinction event that marked the end of the Cretaceous (end of the Mesozoic Era), is perhaps the best known of all the mass extinction events (primarily as this event saw the demise of the dinosaurs); it was not the most severe in terms of the loss of families of organisms, genera and individual species.

The extinction event that marked the end of the Permian (also the end of the Palaeozoic Era), had a far bigger impact on animal life than the extinction event that marked the end of the Cretaceous.

Percentage Marine Invertebrate Extinction (Genera level of Taxon)

Source: Everything Dinosaur

From the graph shown above it can be seen that the extinction event at the end of the Permian resulted in the loss of approximately 68% of all the marine invertebrate genera, whilst the Cretaceous extinction event marked the loss of 43% of marine invertebrate genera.

From time to time major groups of fossils disappear from the geological record.  Many groups of fossils disappear more or less together (roughly at the same point in geological time), the fossils never to be found again in younger strata.  It was partly for this reason that many of the boundaries between geological periods and eras were created by scientists, as they are appropriate points to delineate time.

Species are becoming extinct all the time (this is referred to as background extinction), new species are evolving (speciation), to take advantage of new environmental and climatic circumstances.  There have been a number of major extinctions throughout geological time.  Although, evidence is extremely scarce for extinction events during the Cryptozoic (hidden life Eon – 4.6 bn years to 545 million years ago), it is almost certain that as Precambrian life forms evolved some elements were subjected to extinction events.

The major mass extinctions, known as the “Big Five” have all taken place in the Phanerozoic (visible life Eon).  None of them seemed to have been instantaneous, in most cases it seems to have taken between 500,000 and one million years for the losses to occur.  However, recent evidence regarding the Permian extinction event is that it may have taken place quite rapidly (at least in geological time terms), perhaps taking place over a period of around 100,000 years.

To read more about the mass extinction at the end of the Permian: Can Snails and Oysters provide a clue to Mass Extinctions

Naturally, the collision with a large extra-terrestrial object such as a comet or an asteroid around 65 million years ago would have had a catastrophic impact on life on Earth but there is evidence to suggest that many land and marine animals were already suffering considerable stress before the Chicxulub event.

To review recent articles published on the Cretaceous mass extinction:

Sulphur linked to Cretaceous extinction event: Sulphur in the Sky linked to Dinosaur Extinction

To read more about the Chicxulub impact: Geologists get to the Bottom of the Chicxulub Crater

More information about Chicxulub: End of Dinosaurs set in Motion by Asteroid Collision in Mid Jurassic

The major extinction events, known as the “Big Five” led to the demise of a number of key animal groups, some went completely extinct such as the dinosaurs at the end of the Cretaceous, some such as the Brachiopods were subjected to a number of mass extinction events.  Although Brachiopods still exist today, they do not have the diversity or abundance as during their Palaeozoic heyday.

A Table Summarising the Main Groups of Animals Affected by Mass Extinctions

Mass Extinction in Summary

Table: Everything Dinosaur

A lot of information is available about current climate and environmental change.  It is difficult to interpret this data sufficiently to estimate the current extinction rate.  Many biologists believe that over the last 200 years or so the extinction rate has been much higher than the normal background rate of extinction.  Conservative estimates of current total extinction rates are 5-50 species of animals and plants per day.  This is an alarming figure, taking the mid range point (25) this would suggest that 600 species have gone extinct so far in March 2008.  Such is the loss of fauna and flora that many scientists have labelled this time as “The Sixth Extinction”.  The fossil record indicates that it takes millions of years for the Earth to regenerate biodiversity and establish rich, robust ecosystems.  Mass extinction events seem to have serious implications for larger animals, particularly those at the top of the food-chain, perhaps it is time for H. sapiens to take note.

Frog Blog Week 2 – The Tiny Black Dots

Frog Blog Week 2 – Tiny Black Dots – no movement yet

We have been keeping a careful watch on the frog spawn in the office pond.  The frogs spawned for the first time in our pond last Sunday, so we have decided to keep an observational record of how the tadpoles get on.  Four frogs were in the pond, we suspect one female and three males.  Identifying males and female frogs is not our strong suit, but we estimated the ratio of boys to girls based on the fact that one frog was bigger than all the rest, so we speculated that this was the female.  During the breeding season, the male frogs develop pronounced dark pads on their first digits of the hand.  These pads are present all year round but swell up in the breeding season and help permit males to grip the usually larger females during mating.

Also, the smaller frogs croaked and we think that only the males do this.  The sound does not carry very far, it is certainly not the loudest frog croaking we have heard, many tropical frogs would easier drown out the noise made by these Common Frogs as these animals lack a vocal sac to help the sound resonate.

By Monday the pond was empty and the adult frogs had left, perhaps to hunt in the surrounding rockery, we did not expect to see all four of them together again, but surprisingly on Wednesday all four frogs (one big one and three smaller ones) returned to the pond and there was a lot of activity again but no further spawning.

Frog Blog – Week 2

Picture Credit: Everything Dinosaur

The weather in the north-west of England has been particularly cold over the last few days.  We have experienced strong gales, hail storms and even some snow.  This is the earliest Easter for 95 years, we suspect that the development of the eggs will be dependent on the water temperature, so it may take a while for the embryos to start to develop.  The jelly surrounding the tiny black dots (each no more than about 2mm across), has swollen and this helps the spawn stay afloat and close to the surface of the pond.  In this way the spawn can be warmed by sunlight to the greatest extent (surface water of ponds tends to be warmest).

We have been concerned this week, as there has been a lot building work going on around us and the construction teams have lit several bonfires.  This has led to large deposits of ash and other debris getting blown into the pond.  The silvery “scum” surrounding some of the spawn that can be seen in the picture, is ash that has drifted into the pond, we are not sure what effect this pollution will have on the spawn’s development.

We will have to keep you posted on the spawn’s progress…

Science Bit

Amphibians were the first truly semi-terrestrial animals, evolving in the late Devonian and becoming more numerous and diverse during the Carboniferous and Permian periods before suffering in the late Permian mass extinction.  At the end of the Permian there were about 35 known families of amphibians, many of them considerably larger than their modern counterparts.  After the mass extinction event, at the beginning of the Triassic (248 million years ago), there were about 10 families remaining.  About 70 percent of all the types of amphibians around at the time of the late Permian went extinct.  Today, there are about 4,300 species of amphibians in the world (mostly frogs), but the amphibian class has never fully recovered from the Permian mass extinction.  Amphibians were at their most diverse (in terms of families) and spectacular something like 50 million years before our ancestors (the first mammals) evolved.

Sulphureous Skies Marked the Downfall of the Dinosaurs

Evidence links Cretaceous Mass Extinction to Deccan Traps Eruptions

Disastrous amounts of sulphur dioxide pumped high into the Earth’s atmosphere by the enormous volcanic eruptions taking place in what was to become western India led to the Cretaceous mass extinction according to new research.

New evidence from a team of geologists studying the basaltic lava flows of the region known as the Deccan Traps, suggests that the millions and millions of tonnes of sulphur dioxide thrown up into the atmosphere as a result of huge volcanic eruptions led to dramatic climate change.

Discharging of hundreds to thousands of teragrammes* of sulphur dioxide per year, would have led to global climatic cooling, seriously damaging ecosystems and leading to the collapse of food chains and mass extinction.

Teragrammes* – a measure of weight equivalent to 1 million metric tonnes

The research team has speculated that this was the real cause behind the death of the dinosaurs, marine reptiles, pterosaurs and a number of other animal and plant families 65 million years ago.  The meteor/asteroid impact (Chicxulub) in the Yucatan peninsula in the Gulf of Mexico may have played only a secondary role in the mass extinction event.  Ironically, the strata within the Yucatan region are heavily laden with sulphur, a huge impact such as the Chicxulub event would probably have thrown vast amounts of sulphur dioxide into the atmosphere, contributing to this “overdose of sulphur” and consequent environmental instability.

To read more about the Deccan Traps: Blame the Deccan Traps

Research team member, geologist Stephen Self of the Open University (United Kingdom), commenting on the mass release of poisonous gases due to the volcanic activity stated:

“A semi-persistent gas release of hundreds to thousands of teragrammes of (sulphur dioxide) per year can be envisaged for each Deccan eruption.  There’s plenty of it, and it would be pumped into the atmosphere.”

Yet today, with all the research into global climate change, scientists have little knowledge regarding the behaviour of sulphur dioxide in the Earth’s atmosphere.  Whilst carbon dioxide (one of the main so called greenhouse gases); tends to persist for many years, acting as a climate blanket warming the Earth, sulphur dioxide in massive amounts may behave differently.  The sulphureous gas could reflect sunlight back into space, this would lead to global cooling.  Sulphur compounds tend to be less persistent than carbon compounds in an atmosphere so the effect would not have been sustained.

An additional problem caused by the excessive amounts of sulphur in the atmosphere could be acid rain.  The sulphur particles would combine with moisture in the atmosphere and fall back down to earth as dilute sulphuric acid.  This would have had a devastating effect on vegetation which could have led to the collapse of terrestrial food chains.  Acid rain falling on the oceans could have acidified the seas, leading to the collapse of coral based ecosystems and other calciferous based life forms such as zoo-plankton populations and shelled animals such as the Ammonites.  In this way, the ecosystems in the oceans would also have been seriously disrupted.

The largest of the Deccan Traps volcano’s spewed basalt lava east across the continent and into the sea. The volcanic activity at the end of the Cretaceous was extremely intense.  To gain an idea of the strength of the massive volcano, the 1991 Mount Pinatubo volcano on the Philippines was 1000 times less powerful commented Self.

To read more about the Chicxulub impact: Geologists get to the Bottom of the Chicxulub Crater

More information about Chicxulub: End of Dinosaurs set in Motion by Asteroid Collision in Mid Jurassic

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