Chris Jarvis cleaning the nest box in the Museum Tower Room

A swift return

Chris Jarvis cleaning the nest box in the Museum Tower Room

by Chris Jarvis, Education Officer

‘Look! They’re back! Look!’
This line from Ted Hughes’ excellent poem Swifts shares the excitement generated every year by the arrival of one of the most iconic summer visitors to Britain…. and I’m pleased to announce that they’re here!

Each year at the Museum we eagerly look forward to the swifts returning from their epic migration to southern Africa and back to our tower. Here they will land for the first time in a year, to nest after a 14,000 mile journey on the wing.

Necks of Museum staff are strained as each of us develops a twitcher’s twitch, heads snapping upwards at every bird flying overhead. We all hope to be the first to see a swift returning to the buzz the tower, scoping out the possible nesting opportunities, some no doubt remembering past sites from summers gone by.

Video courtesy Oxford Swift City

With the Museum currently closed due to the global pandemic, this year most staff will be craning their necks to the sky at home, perhaps wondering if any swifts they spot are ‘our’ Museum swifts, or some of the many others that colonise the roof spaces and nest boxes of Oxford and its surrounding towns each year.

Chris cleaning the swifts’ nest boxes with a feather duster

The swifts at the Museum are part of what is probably the longest-running continuous study of any bird colony in the world, started by David Lack in 1948. Because so little is known about these protected and declining populations of birds, every bit of data matters.

Although the Museum’s Swift Warden, George Candelin, is currently unable to reach the Museum during the lockdown, we agreed that it was an essential part of our role as a conservation and research institution to continue the study that has helped us to understand what little we do know about these enigmatic visitors.

Even before the swifts arrive there is a lot to do. With George’s expert guidance, in the last week of April we climbed the winding stone staircase and then the ladders to the very top of the tower to prepare for the swifts’ arrival.

Each of the nest boxes is thoroughly cleaned and their entrance holes dusted to make sure they are free of cobwebs or other obstructions. We then replace the shallow nests used to entice nesting activity. Swifts cannot land to collect nesting material and so have to collect suitable airborne material while on the wing. Their nests are often scanty, basic affairs made of a few stray feathers and other random bits of material they have found blowing about in the wind, so they seem to appreciate a helping hand.

Each of the 80 nest boxes has to be carefully cleaned before the swifts return from Africa

Each of the man-made nests comprises a shallow ring of soft feathers. This is removed from the nest box at the end of each breeding season, frozen to kill off any resident feather lice or other pests, then thawed and gently replaced.

Finally the Swift Cams are put in position and checked, ready to beam intimate shots of life in the tower directly into your home. Now you can follow the breeding season of these fascinating but hard to observe birds from the comfort of your sofa!

All this was completed just in time as, on leaving the Museum, one lucky staff member glanced upwards to see the first swift of the season glide across the sky above the tower. Perhaps a visitor travelling further north to breed, just passing through, or perhaps an early arrival feeding up and replenishing itself before starting its nesting, checking its old nest site is still there and reminding us, as Ted Hughes continued in his poem, that…

They’ve made it again,

Which means the globe’s still working, the Creation’s

Still waking refreshed, our summer’s

Still all to come —

Diving into deep time

Our current First Animals exhibition is extending its run until 1 September, and to mark the extension our Research Fellow Imran Rahman takes a look at how animal life in the ancient oceans was brought to life in our Cambrian Diver interactive installation.

One of the biggest challenges in developing the First Animals exhibition lay in visualising rare fossil specimens as ‘living’ organisms, transforming them from two-dimensional imprints in the rock into three-dimensional animated computer models.

Many of the specimens on display in First Animals were collected from sites of exceptionally well-preserved fossils called Lagerstätten. These deposits preserve the remains of soft-bodied organisms that are almost never seen in the fossil record; things such as comb jellies and worms, as well as soft tissues such as eyes, gills and muscles. Even so, most of these fossils are flattened and two-dimensional, which makes it very difficult to reconstruct what they looked like in life.

Vetulicola cuneata from the Chengjiang fossil site had a large body with triangular openings on either side and a segmented tail. Its three-dimensional shape is uncertain.

To help exhibition visitors visualise the animals in a living environment we worked closely with Martin Lisec and his team at Mighty Fossils to create a set of detailed computer models of a key set of animals. We have worked with Martin before on the video of a Jurassic sea inhabited by plesiosaurs and other marine animals for our Out of the Deep display. That was very successful, but our idea for First Animals was even more ambitious: to create a unique interactive installation called the Cambrian Diver.

The material focused on the Chengjiang animals from the Cambrian of Yunnan province, China, which provides the most complete record of an early Cambrian marine community, from approximately 518 million years ago. Using fossil evidence of the organisms thought to have lived at the time we selected 12 species that were representative of the diversity of the Chengjiang biota.

The first phase was collecting as many materials as possible to be able to create 3D models. As usual, we started with rough models, where we set basic dimensions, shapes and proportions of body parts. Once approved, we moved to very detailed models for the animations, artworks and textures for less detailed models to be used within the interactive application. – Martin Lisec, Mighty Fossils

Images showing a preliminary 3-D model of the lobopodian Onychodictyon ferox in multiple views, with annotations in yellow highlighting changes suggested by Museum researchers.

To provide two-dimensional templates for Mighty Fossils to work from we scoured the scientific literature for the most recent accurate reconstructions available for each of the species.

The predatory arthropod Amplectobelua symbrachiata is a good example. We drew heavily upon a 2017 paper by Dr Peiyun Cong and colleagues, which included a very detailed reconstruction of the head region. This reconstruction shows that the underside of the head of Amplectobelua consisted of a rod-shaped plate, a mouth made up of two rows of plates, and three pairs of flaps with spiny appendages, all details that are included in our 3D model.

Scientific reconstruction (left) and our 3D model (right) of the arthropod Amplectobelua symbrachiata. Left-hand image modified from Cong et al. (2017).

Colour and texture were another consideration. To inform these we looked at living species that are thought to have similar modes of life today. For Amplectobelua, a free-swimming predator, we examined the colouration of modern marine predators such as sharks. Many sharks have countershading, with a darker upper side of the body and a lighter underside, which acts as camouflage, hiding them from potential prey.

We reconstructed our Amplectobelua model with similar countershading camouflage, with blue and red colouration inspired by the peacock mantis shrimp, a brightly coloured predatory arthropod that lives in the Indian and Pacific oceans.

3-D model of Amplectobelua in angled upper (top) and lower (bottom) views, showing countershading.

The next vital step was establishing how the animals moved and interacted with one another. This is a major challenge because in many cases there are no modern equivalents for these extinct early animals. For Amplectobelua we inferred that the flaps on the sides of the body were used for swimming, with the tail fan helping to stabilize the animal as it moved through the water. This agrees with previous interpretations of swimming in closely related animals such as Anomalocaris.

The models were built and textured by Mighty Fossils using the 3D gaming engine Unity. The video below is an accelerated sequence showing how the elements of the model are layered together.

The finished, animated and annotated Amplectobelua model is shown below, and can be zoomed and rotated. All the models generated by Mighty Fossils for the First Animals exhibition are gathered in a collection on our Sketchfab page.

Once animated models of all 12 species were created we placed them in a realistic marine environment. Study of the rocks preserving the Chengjiang fossils suggests these animals lived in a relatively shallow, well-lit sea, perhaps 50 metres deep and characterised by a flat, muddy seafloor. A continuous shower of organic particles is thought to have filled the water column, as in modern oceans.

Reconstruction of the Cambrian seafloor with ‘marine snow’

Based on present-day marine ecosystems, we infer that the number of immobile suspension feeders would have been much greater than the number of predators. As a result, we included multiple individuals of the suspension feeders Cotyledion, Saetaspongia and Xianguangia, which were tightly grouped together, but only a small number of the active predators Amplectobelua and Onychodictyon.

This scene is now populated with animals, including two predators: Amplectobelua (swimming) and Onychodictyon (centre)

The final step involved setting up a camera and user interface to allow visitors to discover the various animals in our interactive environment. For this we worked with creative digital consultancy Fish in a Bottle to identify eight locations, each focused on a different animal.

As the video above shows, users can navigate between locations by touching an icon on the screen, and when the Cambrian Diver sub arrives at a location information about the animal, its mode of life and its closest living relatives is presented on-screen. A physical joystick allows users a 360-degree rotation to look around the scene, and explore the ancient watery world.

This project was significantly bigger than the Out of the Deep work we had done previously with the Museum, mainly because of the complicated approval procedure needed for 20 individual 3D models. Along with three large illustrations, two animations and the interactive application this was a big workload! Fortunately, we managed to finish the whole project on time for the opening of the exhibition. – Martin Lisec

First Impressions: exploring early life through printmaking

Dickinsonia by Claire Drinkwater

by Rachel Parle, public enagement manager

In each of our special exhibitions, we complement contemporary scientific research with contemporary art. In recent years this has included Elin Thomas’s crocheted petri dishes, Ian Kirkpatrick’s migration and genetics-themed installation, and who could forget the enormous E. coli sculpture by Luke Jerram?!

First Animals exhibition is on show until 24 February 2020

For our current exhibition, First Animals, we’ve taken this collaboration to a new level by commissioning original works from a total of 22 artists, all part of Oxford Printmakers Co-operative (OPC) – a group of over a hundred printmakers which has been running for more than 40 years.

First Animals looks at the very earliest evidence of life on Earth, dating back half a billion years. Some of the fossils on display are shallow impressions in the rock – the only direct evidence we have that life existed at that time.

Amplectobelua symbrachiata – one of the incredible Cambrian fossils from the Chengjiang site in China

To kick-start the project we ran a series of workshops for OPC artists to meet the Museum researchers working on the exhibition, and to see the fossils first hand. There were also opportunities to draw directly from these unique fossils, many of which have never been displayed in the UK before.

Discussions between researchers and artists revealed fascinating similarities between these ancient fossils and the process of printmaking. Sally Levell, of Oxford Printmakers Co-operative, explains:

I was completely fascinated by the fossil collection in the Museum, especially the fine specimens from Chengjiang and Newfoundland. They are preserved as mere impressions in the rock, so they are, in essence, nature’s prints.

Each printmaker partnered with a researcher who could answer questions, provide extra info and help the artist decide which specimen or subject to depict in their final print. It’s clear from talking to the printmakers that this direct contact with the experts was invaluable and made the work really meaningful.

Xianguangia by Charlie Davies

We couldn’t have worked without the patient explanations and “show and tell” sessions with the three main researchers – Dr Jack Matthews, Dr Imran Rahman and Dr Duncan Murdock. They were just excellent and their dedication to their work was an inspiration to all of us printmakers.

Sally Levell

Over a period of around seven months, ideas blossomed and printing presses were put into action, with the printmakers exploring the forms, textures and evolution of the fascinating first animals. The final result is First Impressions, an enticing art trail of twenty-five prints dotted around the Museum, both within the First Animals exhibition gallery and nestled within the permanent displays.

Ottoia by Jackie Conway

Such a large group of artists brings a huge variety of techniques and styles, all under the umbrella of printmaking; from a bright, bold screen print in the style of Andy Warhol, to a delicate collagraph created from decayed cabbage leaves! To take part in the art trail yourself, simply grab a trail map when you’re next in the Museum.

Workshop printers inking up their plates

But our foray into fossils and printmaking didn’t stop there. OPC member Rahima Kenner ran a one-day workshop at the Museum where participants made their own intaglio prints inspired by the First Animals fossils. The group of eight people featured artists and scientists alike, all keen to capture the unique fossils through print techniques.

Designs were scratched onto acrylic plates and inked up, before a professional printing press created striking pieces to take home. Participants also explored techniques such as Chine-Collé, the addition of small pieces of paper to create texture and colour underneath the print.

It was a delight to be able to share with the group our enthusiasm for these discoveries in the medium of making the drypoint prints and to share their enjoyment of learning and using the new techniques. Some lovely work was produced in a single day.

Rahima Kenner

A plate about to go into the press
A finished print, using intaglio and chine-colle

The First Impressions project has been transformative for the Museum team and for the Oxford Printmakers Co-operative. Catriona Brodribb describes its impact on the printmakers :

It’s been a great opportunity to challenge one’s own artistic boundaries in terms of stretching the imagination, and for our members to throw themselves into something new, and enjoy responding to such ancient material in a contemporary way.

The First Animals and First Impressions exhibitions are open until 24 February 2020 and are free to visit.

Ice age bones tell tale of human impact on animals

In a series of short videos we look at some of the interesting and sometimes unexpected ways that people use the Museum’s collections.

In this video we meet Dr Chris Stimpson, who uses our collections to identify small bones he has collected from ancient Vietnamese caves. His work helps us to understand the impact humans have had on various species of animal over thousands of years.

Digital reconstruction of a Cambrian ocean

Meet the First Animals

The latest exhibition in our Contemporary Science and Society series, First Animals, tells the tale of Earth’s mysterious early animals, which evolved in the sea over half a billion years ago. Here, Dr Imran Rahman, Deputy Head of Research at the Museum, introduces some of the fossils that form a key part of this story.

From sponges to sea slugs and hagfish to humans, all animals alive today trace their roots back to a common ancestor that lived in the ocean more than 600 million years ago. We have no direct evidence of this first animal, but the fossil record reveals some of its earliest descendants. Our First Animals exhibition explores the evidence for Earth’s earliest animal life, attempting to answer the ‘what’, ‘when’, ‘how’ and ‘why’ of the origin of animals.

Yunnanozoon lividum from the Chengjiang fossil site had a long body with several filament-covered arches at the front and a fin-shaped structure towards the back. It cannot be confidently assigned to any known animal group.

First Animals features the oldest animals yet recovered from the fossil record, including specimens from 571-million-year-old rocks in Newfoundland, Canada. These represent the remains of originally entirely soft-bodied organisms, which have proven difficult to classify because they look so different to living species. However, new research on their anatomy and how they grew, including work by Museum researcher Dr Frankie Dunn, suggests they were early animals.

Charnia masoni consisted of alternating branches arranged along a frond. It is thought to be one of the oldest animal fossils yet found.

Microscopic fossils record the first animal skeletons, which first appeared about 550 million years ago. These include the remains of complete animals, as well as fragments such as spines and scales. Work by Museum researcher Dr Duncan Murdock using a particle accelerator to generate X-ray images of these tiny fossils has allowed us to reconstruct how the skeletons changed as they grew. This helps to establish the modern groups to which these ancient animals belonged, and unravels the mystery of why animals evolved hard skeletons when they did.

Virtual cross-sections through small shelly fossils created using X-ray imaging.

The most complete evidence for the early evolution of animals comes from sites of exceptionally-preserved fossils, or Lagerstätten, which retain impressions of soft tissue as well as hard parts, and include rare soft-bodied animals like worms and jellyfish.

First Animals brings together extraordinary specimens from three key fossil sites: Sirius Passet in northern Greenland (518 million years old), Chengjiang in Yunnan province, China (518 million years old) and Burgess Shale in British Columbia, Canada (508 million years old). This includes 55 unique fossils loaned by Yunnan University in China, as well as specimens from the University of Bristol and the Royal Ontario Museum.

The mollusc Halkieria evangelista from the Sirius Passet fossil site had a long body covered in hundreds of overlapping hard plates, with a large shell plate at either end.
The arthropod Haikoucaris ercaiensis from the Chengjiang fossil site had a semicircular head shield with a pair of large grasping appendages, a segmented body and a short tail.
The worm Ottoia prolifica from the Burgess Shale fossil site had a spiny proboscis and a long trunk that was divided into a series of fine rings.

These exceptionally-preserved fossils reveal the evolutionary diversification of life during the so-called ‘Cambrian explosion’. Through careful study of the fossils, scientists have begun to reconstruct the very first animal ecosystems, which are brought to life in the exhibition through a series of stunning digital reconstructions and the Cambrian Diver interactive installation. This allows visitors to explore a 360-degree oceanic environment in a virtual submersible craft, coming face-to-face with some of the first animals on Earth!

Digital reconstruction of the sea floor 518 million years ago, based on specimens from the Chengjiang fossil site, Yunnan province, China.
Video by Mighty Fossils.

 

First Animals is open until 24 February 2020. Entry is free, no booking required. www.oum.ox.ac.uk/firstanimals.