Angels, dinosaurs and artists’ impressions

We have long used optical telescopes to view distant objects, both living and non-living, making them easier to identify. More recently, technology has provided us with telescopes that record information transmitted over vast distances, allowing us to see distant stars, and even to look back in time as we view the expanding universe.

Similarly, optical microscopes reveal much more than we can see with the naked eye, and electron microscopes, of both scanning and transmission types, make very minute structures visible, although preparation methods require that care must be taken in interpreting what we see. Advances have also been made in the analysis of living and non-living materials that enable us to look at traces of organic chemicals from small samples and, using these approaches, we can analyse the composition of fragments and relate these to their origins. The commonplace use of an individual’s DNA in a blood stain is just one example.

Even armed with this information, we need expert analysis of what we see to make sense of it and this is aided by visual imagery, either generated by computer technologies, or by the hand of an artist. Artists’ impressions are invaluable in re-creating images of things that are no longer present and which we therefore have no chance of seeing. An example comes in the very numerous portrayals of religious scenes, where we are frequently shown images of Jesus, although we have no record of how He looked. The same goes for God, the disciples and all the other characters, as well as Heaven and Hell.

Other beings in religious paintings are given a physical presence that is unlikely or symbolic. The Holy Spirit is frequently depicted as a white dove, while angels have a characteristic appearance that we all recognise [1], with bird wings on a human body that also has arms (an example by Tiepolo is shown above). Taken as being real, these angels would not be able to fly, as the wings of birds have developed from the fore limbs of their reptile ancestors. With arms already present, the wings of angels, and the muscles to operate them, must be located quite differently on the body (I’m not suggesting here that angels do not exist, but that their physical form in paintings and sculpture means that they cannot fly using their wings). It’s an example of where artists’ impressions are very useful in creating images that subsequently have "reality".

Another world that fascinates us, and of which we have no direct knowledge, is that of dinosaurs. We’ve never seen a dinosaur (although there are some modern-day reptiles, like crocodiles, that give us some clues as to behaviour), so how do we know what they looked like and how they lived? We have evidence from which to work, unlike the images created of angels, where there is no fossil evidence. Bones, skin, muscle attachments, and feathers (where present) allow us to reconstruct dinosaurs and then put them into an imaginary landscape. We accept these images, and models based on them, because we believe what experts tell us (quite rightly?). The images are also informed by speculation. In Benton’s book on dinosaurs, with its catchy sub-title [2], we read that the discovery of pigment cells meant that “for the very first time, we knew the colour patterns of a dinosaur, and could use these insights to speculate about dinosaurian behaviour”. Can we really gain information about dinosaur behaviour from colour patterns? Perhaps we can. Later in the book, Benton describes the swimming of Stenopterygius, an ancient reptile from the Mesozoic: 

Stenopterygius swoops after a belemnite, an extinct relative of modern squid and octopus. The belemnite has a fleshy body and fins and swims backwards, just as modern cephalopods do. We know, too, that it has an ink sac, and so, like its modern relatives, likely squirts ink when alarmed, and zips off by blasting jets of water through its siphons. By the time the predator has recovered and snapped a few times at the ink cloud, the belemnite has long disappeared to safety. 

The Stenopterygius is not too fazed, as this is not an infrequent occurrence, and he lines up to chase another group of belemnites. 

Is the language a little flowery here? Admittedly, the book was written for a general audience, and books about dinosaurs sell well, but how critically do we, as members of the public, consider what is said by popularisers?

Further in Benton’s book [2], the dust cover of which shows Tupandactylus in flight (see above), we read this about head crests in bird-like dinosaurs: 

[It is] suggested that such prominent head crests and beaks sheathed in keratin as are seen in various dinosaurs and pterosaurs might have been photoluminescent.. ..[and] we can imagine the elaborate head crests of Tupandactylus flashing different colours at dusk, males and females perhaps showing different patterns, and putting on a spectacular in the crepuscular gloom. 

Please note the use of the words “suggested”, “imagine” and “perhaps” in this quote.

Moving images take artists’ impressions one step further and we are entertained not only by coloured images of landscapes, but also grunts and hisses from different dinosaurs. There is a good selection in the video linked in [3], (complete with an accompanying musical soundtrack to add tension to each scene). How much of this is supported by evidence? I accept that teeth marks on bones correspond to the dentition of certain dinosaurs, but the rest of it?

As we know, dinosaurs are not only important in palaeontology, but also in entertainment and in retailing. Go into any home with young children and you will find many dinosaur-related toys, pyjamas, t-shirts etc. and there is a popular fascination with mythological dinosaurs like the Loch Ness Monster and Sea Serpents. While there are artists’ impressions based on the sightings of the latter two, that is all we have to go on and the transformations of known dinosaur types that appear on clothing, or as toys, may be very far from the creatures that existed hundreds of millions of years ago. Steve Brusatte, reviewing Bentons’ book (see above) remarks that the images of dinosaurs it contains are real and can be used by media professionals, but is this so? Is there a point where palaeontologists can get a bit carried away with their liaison with the world of entertainment?

One important view of science is that it is based on falsifiable hypotheses and this is an approach that I have tried to follow in my research. However, falsifiable hypotheses are not possible with extinct animals (and plants) and, however ingenious our attempts, we are bound to make suppositions about the effects of time: we can design experiments that last hundreds of millions of years, but it is impossible to get the results. It means that palaeontology, including the study of dinosaur fossils, is a highly-informed guessing game, with some practitioners and artists going further into the world of imagination than others. Thus, the need for caution.

 

[1] Roger S. Wotton (in press) Birds and Christian Imagery. In Winged Worlds (eds. Olga Petri and Michael Guida). London, Routledge.

[2] Michael J. Benton (2021) Dinosaurs: New Visions of a Lost World. London, Thames & Hudson.

[3] https://www.youtube.com/watch?v=ZzXGSFVbVvU&t=847s&ab_channel=BBCEarth

How a great auk “flew” from Durham to Glasgow

Fifty years ago, I travelled to Durham University to be interviewed for a PhD studentship to work with Dr Lewis Davies on the blackly larvae (Simuliidae) living in streams in Upper Teesdale. I had always liked moorland and the project involved regular sampling of streams on the Pennines, to collect larvae and then analyse the life histories and production of the populations. Among the questions I was asked at the interview were whether I was prepared to work on my own on the fells and whether I had a driver’s licence, as the studentship came with a short wheelbase Land Rover that would allow access to some of the rougher tracks that I would need to use. I was positive about the first, but I hadn’t passed my driving test and would need to do so. Despite this answer, I was offered the post and accepted readily.

I then needed to take an intensive course of driving lessons that resulted in a pass in what was a very high-pressure test. It was such a relief as I was very keen to go to Durham and I had been impressed by the wonderful city and, especially, the people whom I had met in the Department of Zoology. It wasn’t only the people that impressed – so did the stuffed great auk that had a prominent position at the foot of the staircase in the Zoology Building. I knew that these birds had become extinct but had never before seen a museum specimen and I found it fascinating.

When I moved to Durham, the great auk became a “friend” as I had to pass it as I made my way upstairs to the common room, where we took coffee. Recently, I was intrigued to read about its history, and current location, in a paper by R.A.Baker  in the Archives of Natural History [1]. It is worth quoting from his paper:

The ”Durham” Great Auk had a long association with the University of Durham, from about 1834 to 1977 – a span of over 140 years.. ..Canon Thomas Gisborne (1758-1846), a Prebend at Durham and early benefactor, bought and presented the Great Auk to the new university.. .. When science was re-established at Durham in 1924, the Great Auk was transferred to the newly-built Dawson building and insured against fire and theft. J.J.O.Mason, the Head of Science at the time, recalled “When I came, I begged it for the new department (Science), remarking that some day we should have a Zoology department, which would be glad of it.”.. ..By the late 1970s the Head of the Department of Zoology at Durham, Professor David Barker, decided to sell the specimen.. ..Some disquiet was expressed after the sale was agreed. The sale went ahead on the agreement that the money raised would be placed in a fund “to make purchases to maintain the quality of the zoological specimens teaching collection”.. .. The auction of the “Durham” Great Auk took place at Sotheby’s in London on Wednesday 21 September 1977 and was sold to a Michael Pilkington for £4200.. .Mr Pilkington eventually decided to sell the Auk, and gave the museum [the Kelvingrove Museum in Glasgow, where it had been on loan] the first option on it. The Glasgow Great Auk Appeal, launched the day before the 150th anniversary of its extinction, helped to raise sufficient funds for the museum to purchase the specimen for £30,000 in 1994.

It continues to be exhibited at the Kelvingrove Museum (see below), although I have not been to visit my old “friend”

What is the attraction of extinct animals? We are all familiar with the enthusiasm that many have for dinosaurs and the ammonite fossils of the Jurassic Coast, and these animals became extinct millions of years ago, overtaken by evolution and climate change. Those factors may also explain the much more recent demise of mammoths (like dinosaurs, strong favourites with the public), but very recent extinctions, like that of the great auk and some other flightless birds, were the result of human exploitation. We know that Ole Worm (1588-1654) had a live specimen from the Faroe Islands that he fed on herrings and he also had at least one stuffed great auk in his private museum [2]. With the rise of interest by collectors in rarities, and with little defence against humans, great auks didn’t stand a chance, having already been taken as food and for their feathers [3,4]. Perhaps our fascination with them results from a sense of loss and a recognition that we have been responsible for their being wiped out - and knowing that we will never see one alive? 

It is all a long way from collecting blackfly larvae in Upper Teesdale, but the Durham great auk certainly had, and continues to have, a strong appeal for me. I think it is a pity that it was sold (at what appears a knockdown price), but good to know it “lives on” in Glasgow.

[1] R.A.Baker (1999) Going, going, gone – the “Durham” Great Auk. Archives of Natural History 26:113-119.

[2] A.V.DeLozoya, D.G.García and J.Parish (2016) A great auk for the Sun King. Archives of Natural History 43:41-56.

[3] W.R.P.Bourne (1993) The story of the Great Auk Pinguinis impennis. Archives of Natural History 20: 257-278.

[4] T.R.Birkhead (1994) How collectors killed… New Scientist Issue 1227 May 28th 1994.

Our fascination with dinosaurs

Unlike the majority of scientific finds, descriptions of new dinosaurs are often reported widely by the World’s media, as they grip the imagination of readers and viewers. A recent example is the discovery of Dreadnoughtus schrani in Argentina, where about 45% of the skeleton was found. [1, 2] Individual bones were cleaned carefully and these allowed the reconstruction shown in the illustration below, with the bones recovered shown in white. The skeleton was then completed using assumptions based on a scholarly prediction of the size, and shape, of the missing parts. Dr Lacovara of Drexel University and his colleagues were delighted to have both a femur and a humerus, as measurements taken from these two bones allow a reasonably accurate estimate of the mass of the living Dreadnoughtus to be made - at nearly 60,000 kg, [3] equivalent to more than 10 African elephants. [2]

Both a BBC article, [1] and the one by Drexel University, [2] use the same artist’s impression of a living Dreadnoughtus, although the BBC piece blanks out the background, something that gives context and scale, as does comparison with the size of contemporary humans (see the illustration above). But how accurate is the image of the reconstructed dinosaur to the living form? Fortunately, there are sufficient bones from this specimen to assess the insertion of muscles and thus the outline of some parts of the animal, based on very close examination of bone surfaces by experts. [3] However, while almost all the tail bones were recovered, there is little of the neck and even less of the head, so what is the basis for their appearance in the artist's impression? 

 

There is a problem in making reconstructions of whole animals from skeletal fragments and I’m sure that many dinosaurs are painted with far less evidence of structure than is available for Dreadnoughtus. However, it is the illustrations that grab the attention, although the size of mounted skeletons, or casts, in museums certainly give a sense of the huge size of some of these reptiles. Dinosaurs have been afforded another level of presentational skill in being used in animatronics and computer simulations [4,5] that often feature colour, sounds and even behaviour and may be based on a little too much imagination. Nevertheless, these images are widely held to be accurate by enthusiastic onlookers. 

Our fascination with dinosaurs goes back to the time of the popularisation of fossil hunting and of Natural History in the Nineteenth Century. Among the more famous exhibits of that time are the life-size models of dinosaurs commissioned for the move of the Great Exhibition to the newly-constructed Crystal Palace in 1854. These models remain in the grounds of the demolished Palace (see below) and are still visited by families, whose children delight in their scary nature, despite their obvious lack of life.

In the Nineteenth Century, we knew that dinosaurs existed millions of years before the present and this widely accepted interpretation provided a challenge to those who believed in the literal account of Creation in The Bible. Faced with this conflict, Philip Henry Gosse, wrote Omphalos, [6] in which he advanced a theory that suggested that fossils of such age did not compromise the belief that everything was created over six days, just a few thousand years ago. In the first section of his book, Gosse describes several fossil discoveries accurately and accepts that they were present during different geological time periods, as advanced by Lyell, amongst others. The text is illustrated by artist’s impressions of the living animals in their natural habitats, several in the form of signed woodcuts by Gosse himself and two of these are shown below.

As a brilliant Natural Historian, Gosse was fascinated by the biology of these creatures:

..the most characteristic animals [of the Lias] were great marine Reptiles, of strange and uncouth forms, to which the present world presents us no known analogy. One of these was the Icthyosaurus, which closely resembled a porpoise in form, but thirty or forty feet in length, with a vertical fish-like tail, and two pairs of paddles; a mouth set with stout crocodilian teeth, and enormous eyes. Another form was that of the Plesiosaurus, scarcely less in size than its fellow, which in the outline of its body it resembled: it was distinguished, however, by an extraordinary length of neck, slender and swan-like.. [6]

However, his theory concluded that they had only had the appearance of being alive as everything was created by God at that huge event a few thousand years ago and this included the Earth’s strata and the fossils that they contain. It is, of course, a rather silly theory produced by someone with complete faith in the words of The Bible, yet accepting the logic of geological time. There was no doubting his enthusiasm for dinosaurs, however, even if he believed that they had never existed. Interestingly, in the context of the quote given above, Gosse put forward his view that sightings of “sea serpents” may be explained by the continued existence of reptiles like ichthyosaurs and plesiosaurs. [7]

What is it about dinosaurs that make them more fascinating to us than other fossil animals? In part, it relates to their size, although many small dinosaurs do not have the glamour, and almost mythological status, of larger forms. It is also because we really want to see living forms, rather than impressions of various kinds. Some hope that, like the sea serpents sighted in the Nineteenth Century, aquatic dinosaurs continue to exist, even though the chances are miniscule. In the United Kingdom, we are familiar with the “monster” that is believed to inhabit Loch Ness, but studies using sonar, and other techniques, have, predictably, drawn a blank. Wouldn’t it be fun if we did find a living dinosaur, though?

[1] http://www.bbc.co.uk/news/science-environment-29050114

[2] http://drexel.edu/now/archive/2014/September/Dreadnoughtus-Dinosaur/

[3] http://www.nature.com/srep/2014/140904/srep06196/full/srep06196.html

[4] http://www.nhm.ac.uk/about-us/news/2011/march/age-of-the-dinosaur-exhibition-animatronics-arrive95706.html

[5] https://www.youtube.com/watch?v=C0r5P-PzIPU

[6] Philip Henry Gosse (1857) Omphalos: an attempt to untie the geological knot. London, John Van Voorst.

[7] Philip Henry Gosse (1860) The Romance of Natural History. London, J. Nisbet & Co.