Tag Archives: Cast

The croc in the rock

Number 16 of this series of bad casts is another shocker. All the casts are actually really bad (possibly apart from that pretty darn good bad cast, but this is a cast of a model, not a real fossil). It is amazing how truly bad these casts are and nobody seems to have ever questioned them!

This week’s specimen fails to excite, as you would expect by now.

Another terrible bad cast. A head of a crocodile and a few vertebra. Remember, these bad casts actually belong in a museum. Why?!

Another terrible bad cast. Remember, these casts actually are in a museum collection.

 

The ‘rock’ for this cast is fairly good for a change. Normally, the ‘rock’ (the block the fossil sits on) is just splattered with one colour where you can see the enormously clumsy brush strokes. This one has a little shading, and even a couple of ‘cracks’ thrown in. Nice touch.

The ‘rock’ looks pretty real. This (momentarily) takes your eyes away from what you are supposed to be looking at; the tennis racket in the middle of the slab.

The tennis racket is, of course, the cast of the fossil crocodile head. There are a few other bones included; two vertebrae and a leg bone. Presumably these were on the original fossil.

‘Presumably’, ‘probably’, ‘may have’, are words that often come up in this series of posts, because there is very little information with the specimens. With this cast there is a faded number but no information.

We can make educated guesses about what it is and why the museum possibly has it.

Looking at the snout, I know it is a crocodile skull. Alligators have wider snouts, whereas crocodiles have long thin snouts. It is quite a small specimen, but why have one?

I have a tingly feeling that all of these bad casts may have once been used to illustrate life through time. The collection of casts includes some trilobites, some ancient fish and even a dinosaur tooth. There are some mammals as well (which will come in the next few weeks). This crocodile ‘fossil’ may well have been used to show the people of Plymouth in 1910 a selection of different creatures that lived millions of years ago. Although the fossil is pretty bad, the choice of animal pretty good.

True crocodiles evolved around 200 million years ago. Before these, the ancestors lived on land and looked a little different. In the skull you can see four holes;

Another terrible bad cast. A head of a crocodile and a few vertebra. Remember, these bad casts actually belong in a museum. Why?!

The crocodile skull has four holes on it’s head.

The front two holes are for the eye sockets. The two holes at the back are shared with many other animals, including, birds, snakes, lizards, dinosaurs, rhynchosaurs and others. These two holes (found in diapsids) would have attached muscles to the head. Because they are present in all these animals (including some other extinct ones), it shows that they are all closely related. But crocodiles and birds are even more closely related.

Crocodiles, dinosaurs and birds all belong to the group called archosaurs. This group is defined by the animals within it having two extra openings in the front of the skull (below the eye sockets). Sharing a similar feature like this means that the animals in this group all shared a common ancestor which split apart and evolved into some incredible forms!

Around 250 million years ago, during the Triassic Period, the dinosaurs were becoming the dominant land animals. The ancestors of crocodiles (known as crocodylomorphs) had evolved to take advantage of a number of food sources, including insects, meat, plants and fish. These land loving ancestors felt the pressure of the successful dinosaurs, and around 50 million years later, during the Jurassic Period, crocodiles were living solely in the water.

It was at this time, around 200 million years ago, that crocodiles began to look like crocodiles. Before then they were strange reptiles, some with nostrils on the tops of their heads (rather than at the end of their snouts), and others walks on two legs. They waited patiently in the rivers while large dinosaurs were taking sips of water, and some grew to enormous sizes to tackle this larger prey. The enormous Sarcosuchus was almost as long as a basketball court (around 20m), and would have enjoyed a dinosaur for dinner.

There is more information behind a bad cast than would first appear. A lot of information can be told around this bad cast and we can work out why the museum purchased it.

I may be trying to make this bad cast look extremely good with all the exciting information. Our educated guesses may actually be nothing more than an old Christmas present to a previous curator who left it in the office by mistake. I will never know.

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The king lizard whale

This weeks bad cast doesn’t really look like a fossil, yet it may be from a creature you might recognise.

 

A very very poor quality cast. Those pesky fossil cast dealers.

A very very poor quality cast. Those pesky fossil cast dealers. Doesn’t look like much, does it?

 

I nearly took the photo this way by mistake;

 

Has someone made a cast of a banana?

Has someone made a cast of a banana?

 

Even worse, I almost took the photo this way;

 

Well. Good job I didnt take the photo this way.

Well. Good job I didnt take the photo this way. Otherwise, this could have been mistaken for a cast of something unimaginable. 

Shocking. Not the shape of the fossil (which is a little), but the quality. How can this be sold as a cast of a ‘real’ fossil? It has. Frustratingly it was 108 years ago, so the dealers cannot be challenged by trading standards. There is no time travelling ombudsman. (Now there’s a cool job.)

This is actually a cast of a fossil tooth! The tooth does exist somewhere, but you wouldn’t be surprised to know that there is no information with this specimen about the original fossil. That would be giving us too much!

The label names the tooth as belonging to Zeuglodon cetoides. This extinct beast is actually one you may recognise; Basilosaurus cetoides. It’s an amazing creature, with an interesting history.

In the earl-1800s, huge fossil bones had been discovered in the sediment of the American South. Huge, and fairly common, these had been used as furniture! A couple of bones were sent to the American Philosophical Society for identification. (The American Philosophical Society was set up in 1743 by Benjamin Franklin and John Bartram and early members included three presidents of the United States of America).

The anatomist who looked at the bones (mainly the bones from the spine; the vertebra), Richard Harlan, compared them to the (then) recently discovered dinosaur bones of Megalosaurus and Iguanodon. Harlan thought they looked very similar, but bigger. So he named the creature ‘Basilosaurus‘ meaning ‘king lizard’.

Was this another type of giant extinct lizard? Another new dinosaur discovered? Nope.

Harlan visited England and took some of his newly described Basilosaurus specimens with him to show to the great Richard Owen. (Richard Owen was an incredible British  comparative anatomist who was able to identify an extinct animal by one bone. He was brilliant, but he was also very arrogant, egotistical and deceitful.) Owen looked at the fossils and there were traits that looked like a mammal, and lots of similarities to whales. He renamed the giant ‘Zeuglodon‘ and the American anatomist agreed.

However, there are rules when we name animals and plants (and bacteria). Them rules are there for a reason. The rules of taxonomy are there to make sure that an organism doesn’t have five different scientific names. It also gives priority to the first name given. So in the case of this big whale, it was scientifically described as Basilosaurus before it was called Zeuglodon, so Basilosaurus takes precedent.

This tooth belonged to this whale that lived during the Eocene (around 40 million years ago). About as long as 4 double decker buses, it was a heft animal! As you can’t really see, the teeth were quite chunky and pointy; the shape, and that one fossil had a stomach full of fish indicate that they fed on fish in the oceans. Closely related to modern whales, the Basilosaurus were not their ancestors; this group and the group of modern whales shared a common ancestor that lived around 50 million years ago.

A delightful little sketch of two Basilosaurus. Big, long, whales. Lovely. (Image from here)

A delightful little sketch of two Basilosaurus. Big, long, whales. Lovely. (Image from here)

Beneath this shockingly bad cast is the tale of an whale that once swam in the oceans millions of years ago. Fossils, and potentially casts of fossils, reveal such awesome clues to forgotten worlds. Many of the bad casts in this series do not give the original fossil any thing to get excited about. This bad cast is no exception.

 

 

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A pretty darn good bad cast

There. I have said it. This may be the only time I say it, so I will say it again. This is actually a pretty darn good bad cast. Two casts actually.

Can I say it? Go on. A rather beautiful cast of the top and bottom of a trilobite.

Can I say it? Go on… A rather beautiful cast of the top and underneath of a trilobite.

Apart from a few scuffs where the paint has rubbed off, and a little pink crayon where someone has used this for some children activity as a fossil rubbing, they are actually quite beautiful. (Please don’t use accessioned museum specimens for crayon rubbings. You can buy cheapish casts from fossil suppliers, then place a piece of paper over it and rub a crayon on top. It comes out with a lovely rubbing of the fossil.)

The previous bad casts have been awful. Shocking. So terrible that I have had to really look into what they are supposed to represent. But these are good. Really good in comparison!

What has me even more excited is that there is information written on the back! Can you imagine! A bad cast with information!

Striking gold! Information about a specimen with a specimen! A true rarity in itself!

Striking gold! Information about a specimen with a specimen! A true rarity in itself!

The information tells us what the fossil was, where it was found and who made it. It is a cast of a trilobite, which were pretty successful marine creatures living from around 520 million years ago until the whole group became extinct around 250 million years ago. From species smaller than a finer nail to the big Welsh beasts that would have terrified us paddling in the shallows, trilobites were amazing creatures. Some could roll up into balls for protection, like a woodlouse might today. Others had exquisite spines and spikes growing out of their hard external skeletons.

This cast is of the beautiful trilobite Triarthrus eatoni which lived around 440 million years ago (the Upper Ordovician Period). These casts are actually casts of models of this trilobite. But why the models themselves were made is wonderful is all part of their story.

The Ordovician sediments at a small site in Rome, New York, preserved trilobites and other creatures in unbelievable detail. They were discovered in 1892, and came to the attention of Mr Charles Beecher who was working at Yale University. Beecher noticed that almost everything of this trilobite was preserved, the antennae, and even the gills on the legs.

Gorgeous, almost perfect, pyrite fossils of the little trilobite.

Gorgeous, almost perfect, pyrite fossils of the little trilobite. Image from here.

The specimens themselves were about as long as my thumb. To truly show them off, Beecher made larger brass models with this new understanding of trilobite anatomy. The models are not exactly the same as the fossils, but Beecher appears to have been given a little artistic licence.

These casts are of Beechers models. They show a lot of detail of these extinct creatures. Long antennae coming out from under the head can be seen. These would have been used to sense movement and chemicals in the water. Feathery gills attached to each leg let us see how trilobites were able to breathe under the water. Such soft tissue preservation is very rare in the fossil record, because it decays so quickly.

This will be the only time we get excited about a rather good bad cast. There are a few shockers to come. Lets enjoy this one.

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The road kill fossil

Yes, this is another cast of a real fossil. No, before you ask, I don’t know why it was allowed to be made.

Not a pancake, but an extremely bad cast of the belly of a tortoise.

Not a pancake, but an extremely bad cast of the belly of a tortoise.

The label with this specimen says “Tortoise. Plaster cast on rectangular slab” (‘Tortoise’ has been written in pencil, possibly after the specimen was donated). The label then mentions those two chaps I am beginning to loath; “Presented by Mr J. R. Gregory, per A. G. F. Gregory. April 10 1906”. There is more information about those two fraudsters on these labels than the actual specimen they took a cast of.

It would be ever so splendid to jump back in a time machine to April 1906 and accidental bump into Gregory and Gregory knocking their briefcase full of bad casts over, accidental breaking them all so they never ended up in the museum. If that happened though, these posts would never exist, so I would never have gone back in time. Love a time travel paradox.

Or they could have just sent some more really bad casts in May 1906.

As it is, we are stuck with these bad casts and must do what we can to get them out there.

This ‘rectangular slab’ holds a cast of a tortoise or a turtle. The belly of one in fact. I admit, this is far from the greatest belly ever to be posted on a blog. I also admit that this looks like something that has been flattened by a lorry. A road kill fossil.

The only story I can think this bad cast is trying to tell is that these reptiles have been around for a long time, and fossils of them have been found.

I am inclined to say this is a cast of a turtle. It appears more turtle-like than tortoise. Turtle or tortoise, the story begins a long, long time ago in the Triassic Period, around 220 million years ago.

The origins of turtles is a little murky, but becoming clearer with new finds each year. One current contender for a turtle ancestor is a rather bloated looking reptile called a Eunotosaurus discovered pretty recently in 2008. A funny potential ancestor you might say. You would be right, but fossils of this creature show really thick ribs which curved around its back. This is possibly how the first turtle shells evolved.

The pot-bellied Eunotodaurus. The potential ancestor of turtles (and tortoises and terrapins).

The pot-bellied Eunotodaurus. The potential ancestor of turtles (and tortoises and terrapins). (Image from here)

From this pot-bellied, long-tailed reptile came the wonderful turtles. The ribs fused together to form a hard, protective shell around the turtle. Something strange happened with these animals; these fused ribs grew to a dome like shape, but also fused with some kind of hard amour on the outside of the skin.

Turtles had an advantage by moving to live in the water; their shells. This protected them from predators (although not entirely). They could also swim huge distances, so spread around the world fairly quickly, where some groups stayed and adapted to their little local environment. Some moved back onto the land where they adapted to have tougher harder shells to minimise water loss.

From this pretty awful cast is a fascinating tale, drastically reduced here. Turtles and tortoises are amazing creatures and very close to people hearts. For some strange reason we have an empathy and fondness towards this scaly beast. Their slow lumbering gait along with their old, wise faces both make us all warm inside.

Unfortunately this terribly cast doesn’t quite have the same effect.

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The bizarre beaked beast

When I first saw this bad cast, I got a little excited as I thought it was the head of a dinosaur! We have one other cast of a dinosaur fossil in the museum, but that Iguanodon tooth is really bad. I was wrong, but I would find out that I wasn’t too far off.

A side on view of a pretty big turtle dinosaur creature.

A side on view of a pretty big turtle dinosaur creature.

There was a number scribbled on the back, so a little fumble through our old accession book revealed a long name scrawled in the most appalling handwriting. It seems that 100 years ago the curators thought it would be quite funny to write things down in their most untidiest handwriting with a little smirk on their face knowing that their future replacements would struggle immensely with deciphering their lopsided lettering.

Those funny jokers had no idea that a century later a wonderful research aide, known as Google, would be around. Touché mes amis.

After a couple of attempts of searches, due to several mis-spellings firing blanks, I found the creature. The skull belonged to a rhynchosaur called Hyperodapedon gordoni.

Rhynchosaurs were a group of beaked reptiles that were closely related to crocodiles and dinosaurs. Unfortunately these were not around for as long as their 2nd cousins, and they became extinct around 230 million years ago.

The group was quite successful on their short time on Earth of around 20 million years or so. They were pretty big plant eaters (herbivores), and some could grow as long as two cars. The skull of some species, including Hyperodapedon, holds fairly varied teeth for a reptile, which is presumably why this cast was purchased: the front two teeth on the top and bottom jaws are pretty big, and curved to create a ‘beak’ at the front of the mouth, and the back ones were more flat. This was perfect for eating tough plant material – the front ‘beak’ would slice and the back teeth would grind it down.

The wonderful Hyperodapedon reptile. It was awesome and long, and could eat plants. It couldn't scale down vertical surfaces.

The wonderful Hyperodapedon reptile. It was awesome and long, and could eat plants. (Contrary to this illustration, it couldn’t scale down vertical surfaces.)

Hyperodapedon gordoni was a pretty cool plant eating reptile and it is likely that they grazed in herds of hundreds of individuals. The large two holes at the back of the head shows it’s relationship to the archosaurs (the group that includes the crocodiles and dinosaurs). These two holes are found in the skulls of animals from this groups, and a few others (including tuataras, lizards, snakes and the avian dinosaurs around today – the birds). The overarching group that holds all of these creatures with two extra holes in their heads is called the Diapsids.

View from the top. The two holes close to the front are for the eyes. The two big holes near the back are for something else.

View from the top. The two holes close to the front are for the eyes. The two big holes near the back are for something else.

In Hyperodapedon these two holes would have attached big muscles from the head, and allowed the jaw to open pretty big. This would have been very useful for slicing effortlessly through the tough vegetation it relied on.

This isn’t the greatest cast ever made. But, to my sheer delight, I have found another museum that has a similar cast and is actually worse! If you have seen some of the other posts on bad casts, you know that we have some pretty bad plaster casts of fossils. You can also imagine how I grinned from ear to ear when I saw this beauty on another museum’s website!

This cast from the Grant Museum and is most definitely a bad cast, a worst cast than mine! My victory, and smugness, is short lived. I have just realised that although their cast is pretty awful, they are actually using it. Something I am not doing.

This example from the wonderful Grant Museum of Zoology, is a lovely way of how we can use our bad casts. Perhaps we should not be ashamed of them and hide them away. Let’s be proud! Lets get them out!

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The bad cast of an amazing Iguanodon tooth

On one day a week, every week of the year, something magical happens. Twitter comes alive with beautiful remains of creatures that lived millions of years ago. The Twitter regulars know this as #FossilFriday, and no doubt salivate at the very thought that on Friday a plethora of enigmatic beasts will jaunt through their timelines with stunning perfection.

All the photos tweeted on #FossilFriday are amazing. We see photos of fossils from long, long ago (like trilobites and ammonites), and others of more recent beasts that roamed only a few tens of thousands of years ago (like cave lions and mammoths), and some of fossils of marks in the sediment made by creatures long ago. All the fossils are beautiful and each is unique. Watching the feed dance with exotic creatures that were once alive long ago every Friday is pure awesomeness.

It was one of these wonderful Fridays, amongst the incredible photographs being tweeted and retweeted, that something jumped out, which was tweeted by the Natural History Museum team (@NHM_London). At first glance they may not look like much, but these are stunningly exquisite fossils, which were actually some of the most important fossils finds of the early 1800s.

Two teeth that were to define a whole Class of unbelievable animals. Image reproduced from here.

Two teeth that were used to define a whole new group of unbelievable animals. (Image reproduced from here)

This particular photograph jumped out because I recognised it instantly with pure awe. They are two teeth of one of the first dinosaurs ever discovered and named; Iguanodon. What is even more exciting, is that we have a rather bad cast in our museum, of the tooth on the right!!

A very bad cast of a very important tooth!

A very bad cast of a very important tooth!

So for one of the most amazing fossil teeth discovered, we have this very unworthy cast! I’m still not to sure how the guys who made these casts got away with it! What’s even more frustrating is that sometimes with a specimen there is an old card record which gives a little more information; the card should have a lot of information on it, however most of the time this is what we have;

A typical card record which accompanies the fossil casts. You may like to note any lack of information about the original it was cast from, related stories, when it was cast, what it was cast from, who did the casting...Just general useful bits of information.

A card record which accompanies the fossil cast. You may like to note any lack of information about the original it was cast from, related stories, when it was cast, who did the casting…Just general useful bits of information.

The information on this card is like me saying ‘I am a human’, and not actually saying where I was born, who made me, when I grew up, where my grandparents lived…. These bits of information are key to bringing specimens alive with stories. As it stands, Mr J Gregory has a ruddy lot to answer for. (That chap and A. G. F. Gregory sold us an awful lot of bad casts back in 1906 *shakes fists*.)

Fortunately, there is a quick witted museum curator is on hand to delve into the sparkling history of this little cast.

These teeth were found by Mary Mantell along the roadside in Sussex in 1820 (or 1821 – the records are not too clear). The tale goes that she was with her husband while he was on his medical rounds. She noticed the strange rock and moved the grains with her fingertips to reveal, for the first time in over 125 million years, a shiny, dark brown tooth. The husband, Gideon Mantell, had been finding very large bones in the rocks of the Sussex Downs. These teeth, he immediately thought, could be the teeth of this unknown giant he had been finding, so he devoted the next few years to looking for more specimens.

The determined, passionate fossil hunter Gideon Mantell. (Image from here)

The determined, passionate fossil hunter Gideon Mantell. (Image from here)

Mantell had passed his fossil finds to the top leading scientists of the time, including William Buckland, Charles Lyell and the great French anatomist, Georges Cuvier. They didnt think much of the fossils, with the identifications ranging from fish teeth to rhinoceros teeth. But in 1824, the assistant curator at the Royal College of Surgeons recognised that these fossil teeth were very similar to the teeth of an iguana; but they were over 20 times as big!

More fossils came to the surface, including some nice specimens from Maidstone in Kent. With the new finds, and confidence about what he had, Mantell presented a paper to the Royal Geological Society of London in 1825, where he named his beast Iguanodon (meaning ‘iguana tooth’) 

This was quite a find. An enormous reptile, which was a herbivore (plant eater). This was only the second very large reptile to be named. The previous year, William Buckland has named a big carnivore Megalosaurus (meaning ‘great lizard’). 6 years after his paper on Iguanodon, Mantell discovered the fossil remains of another giant lizard which he named Hylaeosaurus (meaning ‘belonging to the forest’).

What were these three great lizards? Nothing living looked anything like these giants. One man took it upon himself to name the group to place these extraordinary animals in. The man was Richard Owen.

The rather sinister looking Richard Owen. It's the eyes. (Image reproduced from here)

The rather sinister looking Richard Owen. It’s the eyes. (Image reproduced from here)

Owen was a brilliantly intelligent anatomist in the mid-1800s. Owen was a genius; he could identify extinct creatures from a single bone. However, he also ruffled many feathers, include Darwin and Huxley. And Gideon Mantel.

Owen gave a lecture to a large audience at the British Association for the Advancement of Science in Plymouth about these massive lizards. It was in this lecture that he first used the name ‘Dinosauria’ (meaning ‘terrible lizards). He coined this term based on the three animals that had been discovered. Their size and forms were unlike anything known living or extinct, and were distinguishable enough to place them into a completely new group of animals; the Dinosaurs.

These amazing teeth played a vital role in the naming of one of the most familiar species of animals that live on Earth; Iguanodon. The teeth, which had caused so much debate about what they actually were, were also important in coining the name of the most familiar group of animals on the planet; the dinosaurs. This group started off with three know species, and has grown enormously into well over 1000 species identified in the fossil record (not including the birds).

This cast represents one of the most important palaeontological discoveries ever made. It is such a shame it is so bad.

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The most pointless cast?

This is actually one of the worst bad casts I have seen. It is not the worst. I am saving that one. That’s a beauty which you have to see to believe.

Back to this bad cast. It is bad. Really bad. What makes it so bad is that it is actually pointless. This is a cast that doesn’t even need to be here. That may sound harsh, but it will make sense soon (plus, it is just a plaster cast, not a pet).

I’ve said it before, casts of fossils are great. There are not enough of the beautiful rarities for each museum in the world to have one. Real dinosaurs bones are too heavy to mount in museum display spaces, so casts are used. (The infamous Dippy, the Diplodocus skeleton at the Natural History Museum, is a cast. When I volunteered there many moons ago, the tail was slouched down on the ground and people used to help themselves to the tail bones. [This is stealing, and is not recommended] More casts of the tail vertebrae were taken out to replaced those stolen ones.)

So casts of fossils are useful. Even some of the bad ones had a reason. This one, however, baffles me. Why did they…? Who even…? What the …?

One of the worst fossil casts in my museum. And truly pointless.

One of the worst fossil casts in my museum. And truly pointless.

If you don’t recognise it, dont worry – that is probably due to the fact that it is a really gawd awful cast than your palaeontological skills. It is the cast of a Crinoid (a fossil of a sea lilly). (Click here to see what they should really look like.)

Crinoids are beautiful marine animals which have ‘arms’ that float upwards, grabbing their food to bring to their mouth. They have a long ‘stalk’ which attaches them to the marine sediment. Just imagine an upside-down starfish held to the sea floor by a long thin stem out of the sea floor! In fact, that is not really too far off, because Crinoids are closely related to starfish, and belong to the same group, the Echinodermata.

The earliest fossils of these creatures have been found in rocks that are very old, around 480 million years ago (during the Ordovician Period). These beautiful animals are still around today. Their vibrant, colourful forms brighten up the seas where they were found. The ancient Crinoids were just as likely to be as colourful as well.

Because they are still around today, we know quite a lot about these fossils. The young (larval) stage free float in the water for a few days before settling to the bottom and attaching itself to a hard surface. Here, it will spend the rest of its life, feeding and producing more sperm or eggs. They feed by using their fine feathery arms to filter tiny plankton (tiny organisms that float in the water).

This is actually a pretty cool animal. And this fossil cast we are very lucky to own, can tell quite a detailed story, from its origins around 480 million years ago, to floating with the warm currents today. it’s a big shame that it is too terrible to ever bring out and tell that story! Am I being too harsh to say we never even needed this cast? No.

Along the Jurassic Coast, in the South West of England (around 2 hours drive from Plymouth), you can find loads of Crinoid fossils which lived around 150 million years ago. We have quite a few very bad ammonites from Lyme Regis, countless belemnites from Dorset and even a fossil crab from Dorset. But for some reason we do not have any Crinoids from Dorset!

Perhaps this cast was an afterthought. The museum was about to open, and panic set in, we forgot to get a Crinoid fossil to show the diversity of life on Earth. So they ordered a cast. A truly pointless, bad cast. At the time someone was laughing as they made this cast. Little did they realise, that 102 years later a curator would be weeping as he tried with all his might to compliment this cast in his little office under the stairs. And probably failed miserably.

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