Creating a Better Future for the Arctic: The Role of Natural-History Museums

May 8 to 10: Meeting of the Arctic Natural History Museums Alliance

A few years ago, during Sweden’s chairmanship of the Arctic Council, the director of its national natural-history museum and I met in South Korea during the IUCN World Conservation Congress. We decided that the national natural-history museums need to step up and actively share our knowledge of the Arctic regions and to be more ambitious in our sharing of that knowledge with scientific colleagues, public-policy decision-makers and the general public.

We did a call out to the directors of the national natural-history museums of the eight Arctic Council states to get things started. We met in April 2013 and again in May 2014. Our focus was determined to be collections access, research collaboration and public outreach.

Three people pose together, one holding a narwhal tusk.

Left to right: Kirk Johnson, Director of the Smithsonian Institution’s National Natural History Museum; Meg Beckel, CEO of the Canadian Museum of Nature, holding the Narwhal Mace; Jan Olov Westerberg, Director General of the Swedish Museum of Natural History. Image: Kirk Johnson © Kirk Johnson

For the May 2015 meeting, our plan was to meet with all eight national natural-history museums from the Arctic Council states. And then the reality of changing leaders and conflicting schedules kicked in. The willing and available carried on with reports from our colleagues and spent three days in Washington with other national natural-history museums of the Arctic Council states. Our focus during this meeting was on collections digitization, research contribution and collaboration, and impactful public programming and outreach.

The first day began with a tour of the Smithsonian natural-history museum’s off-site collection facility. Mark Graham, Ph.D., our VP of Research and Collections, was available for this part of our gathering. I was mid-air at the time, making my way from Ottawa to Washington. Following an informal lunch that included a front-row view of the World War airplane fly-by, our meeting opened with a panel discussion about the need for a human perspective when speaking about the Arctic.

The panellists and moderator during the presentation.

The meeting began with an expert-panel presentation on the need for a human perspective in discussions about the Arctic. Mark Graham © Canadian Museum of Nature

The panel presentation included speakers from science, public policy, indigenous governance, the Arctic Council and natural-history museums (yours truly). The panel was followed by a magical dinner for major donors (and museum colleagues) in the atrium of the Smithsonian’s natural-history museum.

Tables set up in the atrium.

The atrium of the Smithsonian’s natural-history museum set up for the donor evening. Image: Meg Beckel © Canadian Museum of Nature

Saturday morning we were back to business. The morning’s focus was collections access. Like other museums around the world, we are challenged to prioritize which collections to digitize with our scarce resources so that we make the data that are most needed available in a form that is useful.

Also, we need to determine which data management sites are most used, and are thus a place for our data. From Encyclopedia of Life (EOL) to Scientific Collections International (Scicoll), we have many existing tools that we can continue to post our data to, and some new ones are being discussed.

We are suggesting an Arctic portal be created for both EOL and GBIF (Global Biodiversity Information Facility) so that visitors to those sites know that Arctic data are available and that new data are welcome. With the challenges to the environment in the Arctic, we must step up and play our part in creating and sharing knowledge about the Arctic so that better and more-informed decisions are made in the future.

Collage: Visitors in an activity room.

Q?rious at the Smithsonian’s natural-history museum, where organizations presented their perspectives on the Arctic during the meeting. Image: Meg Beckel © Canadian Museum of Nature

During our discussions, we took a break to visit Q?rious, the Smithsonian’s discovery centre. Arctic organizations were stationed throughout to share their perspectives with visitors, while the education team tested an Arctic board game on visitors.

Arctic research is another area of focus for our group. The questions we asked were “Which research forums are the most relevant to our work? And where can our research add the most value?”

At this stage, we have decided to focus on the International Union for the Conservation of Nature (IUCN), the Arctic Science Summit Week (ASSW) and the Arctic Council working groups. Most of the Arctic natural-history museums are already involved in one or all of these, so it makes sense to build on what we are already doing and where we already have some presence.

People looking at the floor map.

Our first project for engaging the public will be the creation of a giant floor map that shows the circumpolar region. Image: Mark Graham © Canadian Museum of Nature

Outreach, public programming and visitor engagement are areas where we can support each other, share content, share learnings and collaborate to contain costs.

Our first project will be the collaborative production of a giant round floor map of the circumpolar region.

Second will be some form of web-based outreach from each other’s scientists to our school visitors, building on what we are each already doing within our own museums.

Third is a collaborative photo-based exhibition that we hope to inspire the Arctic Council to invest in, given the US chairmanship’s focus on public outreach and awareness of the challenges, opportunities and shared responsibilities in the Arctic.

All in all, it was a productive and inspiring gathering of fellow museum leaders committed to creating a better natural future for the Arctic. Kirk Johnson said, “Natural history museum can save the world.” I agree, so let’s get at it.

Lots ahead and more news to come.

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Odyssey under the Skin

The automatic door opens as I sweep into the special exhibitions hall on the fourth floor of the Canadian Museum of Nature. Inside, a giant squid kicks off the “Animal Inside Out” exhibition. Complete sea animals and skeletons stand waiting in the first section of the hall.

As I enter the second section, I am immediately taken up by magical scenes of dissected bodies. I see a bull with all its muscles hanging out in full splendour, followed by a galloping giraffe showing off its slender cervical muscles like a five-meter tall headdress. Just beside it stands a camel, half of its body exposed, nodding its head in a frozen gesture. Further down, the complex blood vessel system of an ostrich is on display with stunning accuracy.

The plastinated bodies of camels in the exhibition.

Many of the plastinated bodies showcased in Animal Inside Out reveal an organism’s constitution in a unique way. You can distinguish the internal organs in detail. Image : Kamal Khidas © Canadian Museum of Nature.

Organs belonging to the ten body systems are shown in eloquent detail. In particular, this includes astonishing insights into the cardiovascular and muscular systems. These fabulous bodies are undressed to show off their true nature!

View of a bull specimen from the Animal Inside Out exhibition.

On this bull, as with many of the specimens exhibited in Animal Inside Out, you can study the muscles that make up an organism with the help of an anatomical atlas. Image : Kamal Khidas © Canadian Museum of Nature

I have taught many subjects ranging from biology and genetics to animal behaviour. When I was teaching comparative anatomy, I made use of textbooks and anatomical atlases to show the structures that make up the body, but observing these phenomena on real animal corpses was much more convincing for the students. The word anatomy comes from the Greek word anatemnein which indeed means to dissect or cut up. Today, I am in charge of the Vertebrate Collections at the Canadian Museum of Nature, which include millions of various anatomical parts. This has allowed me to see and examine living organisms from all angles. Even so, this exhibit taught me a unique way of revealing the true nature of living beings.

An ostrich specimen, showing the capillary network.

Even the capillary network (very fine blood vessels) of an ostrich can be seen in Animal Inside Out in its original three-dimensional form…as if the rest of the body’s building blocks had been blown away to leave only this network in place. This feat would be impossible to do otherwise. Image : Kamal Khidas © Canadian Museum of Nature

My anatomical teachings would have been even more successful if I had been able to use plastination—a technique used to prepare the specimens shown in this exhibition. Among the 600 skeletal muscles that make up the body, only some were readily identifiable on the previously frozen skinned specimens that I was using; in this exhibition, they are almost all there. The spatial configuration of internal organs is true to life, making it easy to figure out the interrelations between body systems.

Cross-section view of an elephant.

One of the advantages of the technique used in Animal Inside Out is that once the bodies are plastinated, they can be cut up into very fine slices to reveal anatomical details that are otherwise invisible. Indeed, you can see the detailed internal structures in this cross-section of an elephant, right down to the histological level. Image : Kamal Khidas © Canadian Museum of Nature

The introduction of plastination goes back to 1977 when an anatomist from the University of Heidelberg, Gunther von Hagens, came up with a more practical method of observing human internal organs in situ. The somewhat painstaking technique consists in replacing all the water and fat in the organism (up to 70% in fact) by injecting an epoxy/silicone polymer that hardens afterwards; this produces a dry, odourless specimen that can be handled easily and lasts a long time.

The giraffe presented in the Animal Inside Out exhibition.

Animals are presented in many forms. Here a skinned giraffe stands beside another life-size specimen that has been reassembled from a series of fine cross-sections. Image : Kamal Khidas © Canadian Museum of Nature

The word plastination is derived from the Greek “plassein” which means to give form. A bargain for anatomists! Plastination has opened interesting perspectives in several disciplines, in particular teaching. In fact, human anatomy professors have greatly benefited from it. It was well received by the scientific community, as witnessed by the many scientific papers on the subject to date. The technique even broke into the public arena in 1995 with BodyWorlds, an exhibition on the human body.

Two caribou specimens.

Bodies exhibited in Animal Inside Out were mounted to reflect natural postures that show movement, such as these two caribou, or reveal a behaviour trait. Image : Kamal Khidas © Canadian Museum of Nature

Animal Inside Out is a fascinating anatomy lesson! I see it as a mix of science, technology and art, not just pure and simple anatomy. Nature has so many wonders and there are so few opportunities to contemplate them! This exhibition is a must-see.

A human body in the Animal Inside Out exhibition.

The presence of a human body is an unhoped-for opportunity to make detailed comparisons between our own bodies and those of the various animals on display.
Image: Kamal Khidas © Canadian Museum of Nature

Text translated from the French.

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My Visit to a New York City Basement

Popping your leftovers into the freezer is your best bet for saving them for later. Keeping things cold is also the best method for preserving DNA molecules. To learn about the tools and techniques for the world-class care of tissue samples used for DNA research, I travelled to a basement in New York City.

The American Museum of Natural History looms large over the west side of New York’s Central Park. Behind its grand granite façade, creatures of all kinds are on public display. Walking through this museum—one of the world’s largest—is a rich experience of our planet’s animals, plants and minerals.

Exterior view of the museum entrance.

The American Museum of Natural History’s grand entrance on Central Park West in New York City, USA. Image: Roger Bull © Canadian Museum of Nature

Collage: A mounted dinosaur skull, a mounted elephant, mounted mammal skeletons.

Dinosaurs, and elephants, and primates! Oh my! Just a few of the creatures on public display at the American Museum of Natural History. Image: Roger Bull © Canadian Museum of Nature

Behind the scenes, however, there is much more to the museum than its impressive exhibits. Just like the Canadian Museum of Nature, the American Museum of Natural History (or simply “the AMNH”) houses large collections of animal, plant, fossil and mineral specimens. The museum’s research scientists—and researchers from around the world—use these collections to better understand the diversity of life on Earth.

Increasingly, scientists use information stored in DNA molecules to study biodiversity. Ideally, these DNA molecules are extracted from tissue samples specifically collected for this purpose. These tissue samples need special care and storage conditions to preserve the valuable molecular information. The key is cold temperature—MUCH colder than your home freezer can provide.

On the hunt for supercold freezers, I walked past the AMNH exhibits, through an inconspicuous brown door, and down a flight of stairs. Now in the basement, a maze of utilitarian hallways and workshops led me to the Ambrose Monell Cryogenic Collection.

Julie Feinstein, the manager of the collection, keeps careful watch over the large insulated stainless steel vats that house roughly 100 000 tissue samples. Eight inches of liquid nitrogen in the bottom of each vat keeps the samples at a seriously chilly −160°C. At this temperature, most molecular movement stops, which prevents the degradation of the samples. The information of DNA is preserved in perpetuity.

A row of metal tanks lines a wall.

These cryovats are used to store tissue samples at −160°C. At this temperature, the DNA in tissues is preserved. Image: Roger Bull © Canadian Museum of Nature

Collage: Two people at work in the collection.

Left: A technician at the Ambrose Monell Collection retrieves samples to send out to a researcher. Right: Julie Feinstein holding a very cold freezer rack. Julie is the manager of AMNH’s cryogenic collection. Images: Roger Bull © Canadian Museum of Nature, © AMNH/R. Mickens

This cryogenic collection, like other museum collections, is not a static assemblage of objects locked away for eternity. Specimens come and go, arriving with researchers back from the field or sent out to curious scientists anywhere in the world.

Keeping track of incoming and outgoing samples and the data associated with them requires meticulous care. I spent two days observing this careful work as I peered over the shoulders of Svetlana and Nisa, the collection’s technicians and frontline workers. They deftly handled the traffic of samples, which are stored in small, barcode-labelled, polypropylene tubes.

Collage: Hands manipulate tissue vials.

Tissue samples are stored in small, barcode-labelled tubes. These are stored in boxes that are then loaded into freezer racks. Image: Roger Bull © Canadian Museum of Nature

Cold is the key for a good tissue collection, but so too is organization. This is one of many important lessons learned during my time in the New York City basement.

My visit was part of a knowledge-gathering process that is just getting started. The Canadian Museum of Nature would be a natural home for a cryogenic tissue collection.

Before we roll cryovats into our research and collections facility, we need to be well versed in the best way to establish and manage such a collection. If all goes well though, we will have the coldest and best organized freezers in the country.

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Bird Nests: A Little-Known Collection

People who get a chance to visit the museum’s Bird Collection at the museum’s Natural Heritage Campus are often surprised by the scope of this collection. In addition to bird specimens, it also contains ancillary collections that document various aspects of bird biology.

In the 19th century for example, when egg collections were a popular (and legal) hobby, bird nests were sometimes collected, and some of these were later bequeathed to the Canadian Museum of Nature. Over the years, the museum put together a representative collection of nests for reference. This material also helps document the diversity of nesting habits among different species.

A woman stands by an open specimen drawer.

The nest of a Greater White-fronted Goose from Alaska, USA, is examined by museum volunteer Carol German. Image: Michel Gosselin © Canadian Museum of Nature

A taxidermied bird specimen.

A Greater White-fronted Goose (Anser albifrons) specimen. Image: Martin Lipman © Canadian Museum of Nature

Geese and ducks build their nests from down that they take from their belly. This operation leaves them with a patch of naked skin that facilitates incubation, creating a direct contact between the eggs and the bird’s body heat. When a bird that is incubating has to leave the nest, it covers up the eggs with down from the nest. This down serves as both camouflage and insulation.

Collage: Two bird nests.

Left: A Ruby-throated Hummingbird (Archilochus colubris) nest. Right: A Red-billed Streamertail (Trochilus polytmus) nest. Images: Michel Gosselin © Canadian Museum of Nature

The Ruby-throated Hummingbird is a common species in the Ottawa Region. Several species of hummingbirds build nests made of insulating plant fibres, like the one shown above. Then, they cover the outside of the nest with pieces of lichen glued together using spider webs. The green plumage of the female as it sits in the nest is a marvellous finishing touch to the camouflage, making it look like a simple growth on a branch.

The Red-billed Streamertail nest shown above is from Jamaica. In a tropical climate, thermal insulation is less critical and the nest of the streamertail looks like a crude plate, just big enough to receive the eggs.

Two hands hold an open box containing a nest.

A Chimney Swift (Chaetura pelagica) nest. Image: Michel Gosselin © Canadian Museum of Nature

A taxidermied bird specimen.

A Chimney Swift specimen. Image: Martin Lipman © Canadian Museum of Nature

Swifts vaguely resemble swallows. The Chimney Swift—a widespread species in Canada—puts its nest inside a hollow tree trunk or a chimney. The nest is a simple platform made of dried twigs collected by the swift while in flight from treetops. These are then glued to a tree trunk or a chimney using the bird’s sticky saliva. Some Asian chimney swifts have nests that are entirely made of this saliva. These are sometimes used in oriental cuisine as a soup ingredient.

An overhead view of a nest in an open specimen drawer.

A Rufous Hornero (Furnarius rufus) nest. Image: Michel Gosselin © Canadian Museum of Nature

The Rufous Hornero is a bird from South America whose name “Hornero” derives from the special shape of its nest, which looks like an old-fashioned oven. This bird is as big as a robin and builds its nest using mud, which dries to become hard as brick. The example shown here was given to the museum in 1986 by an Argentinian diplomat stationed in Canada.

An open specimen drawer containing nests and a boot.

The boot contains a House Wren (Troglodytes aedon) nest. Image: Michel Gosselin © Canadian Museum of Nature

A taxidermied bird specimen.

A House Wren specimen. Image: Martin Lipman © Canadian Museum of Nature

There are some 10 000 extant bird species that have colonized almost all parts of Earth. They have also developed extremely diversified nesting methods.

The House Wren can make its nest in all kinds of cavities, often near human dwellings—hence its common name. Back in 1935, one of them set up house in an old boot left in a woodlot. After the nesting period, the property owner donated this strange nest to the museum.

Two hands hold an open box containing a bird nest.

A Sedge Wren (Cistothorus platensis) nest. Image: Michel Gosselin © Canadian Museum of Nature

The Sedge Wren highlights another aspect in the amazing diversity of birds’ nesting habits. When he returns from its hibernating grounds, located in the southern United States, the male from this species builds several nests. The females arrive later, and when couples are formed, it is up to the female to choose the nest she wants to use, whereupon she lines the inside with feathers or fine plant fibres.

Collage: Two taxidermied bird specimens and two nests.

Top: A Baltimore Oriole (Icterus galbula) specimen and nest. Bottom: A Chipping Sparrow (Spizella passerine) specimen and nest. Images: Martin Lipman and Michel Gosselin © Canadian Museum of Nature

The Baltimore Oriole nest shown above was collected in Ottawa in April 1926. Instead of the plant fibres normally used by orioles, you can see that this nest is made of mop strands and a little horsehair. What’s more, the mop strands are completely blackened by soot. This simple nest conjures up the bygone days of Ottawa when coal was used for heating (and for running locomotives into downtown), and horses were widely used as a means of transportation.

The Chipping Sparrow nest above was also collected in Ottawa, though in 2014. Here the bird used nylon fibres from nets used to protect evergreen trees in winter. Other times, other means…

A hand holds a stick from which a nest hangs.

A Baya Weaver (Ploceus philippinus) nest. Image: Michel Gosselin © Canadian Museum of Nature

Weaver nests are among the most elaborate bird nests. Above, we show the nest of a Baya Weaver from the Indian sub-continent that was donated to the museum several decades ago. The bird (actually only the male in this case) must collect almost 1000 plant filaments in order to weave the nest and create a maze inside, which is basically used to outsmart predators.

Translated from French.

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Dinos of Canada gets my Stamp of Approval

Well, it’s official! It’s been a year in the making, but I’m finally able to talk about it: Canada Post’s sensational new stamp series, Dinos of Canada.

I got involved with the project early on, when Canada Post asked me to be the scientific advisor for the stamps. My duties were twofold: to help decide which prehistoric animals would be featured on the stamps, and to vet the artwork and related text for accuracy.

Pictures of the five Dinos of Canada stamps

The new Dinos of Canada stamp lineup. From left to right, the featured prehistoric animals are: Euoplocephalus tutus, Chasmosaurus belli, Tyrannosaurus rex, Ornithomimus edmontonicus, and the marine reptile Tylosaurus pembinensis (a mosasaur, not a dinosaur). Image: © Canada Post

I initially came up with a list of 24 dinosaurs and other prehistoric organisms as possible contenders for the stamps. These contenders ranged from all parts of Canada, all branches of the Tree of Life, and all periods of the geologic timescale. Narrowing down the contestants to just five species was difficult, and there were many worthy animals that did not make the cut.

Closeup of the stamp featuring Ornithomimus edmontonicus. Visitors to the museum’s Fossil Gallery can the skeleton of this dinosaur. Image: Dan Smythe © Canadian Museum of Nature

Closeup of the stamp featuring Ornithomimus edmontonicus. Visitors to the museum’s Fossil Gallery can see the skeleton of this dinosaur. Image: © Canada Post

For each of the finalists, I benefited from having direct access to superb fossil remains from each one, all held in our museum’s national fossil collection. The Canadian Museum of Nature, in fact, has the type specimens for Ornithomimus edmontonicus, Chasmosaurus belli, and Euoplocephalus tutus. These are the first of their kind used to describe the species, and have immense scientific and historical value.

We wanted to be able to say something interesting about each of the featured species, and to draw a connection to Canada—to the places where they were found and to the people they honour.

For example, the ostrich-mimic Ornithomimus edmontonicus is named after a rock unit called the Edmonton Formation where it was found, which itself is named after the city of Edmonton.

The name of the horned dinosaur Chasmosaurus belli likewise honours Robert Bell, a former natural sciences professor at Queen’s University, and administrative head of the Geological Survey of Canada.

Jordan Mallon holding part of the frill of Chasmosaurus belli.

It’s always important to do your background research when advising for a project as big as Canada Post’s new Dinos of Canada stamp series. Thankfully, many of the dinosaurs featured on the stamps are also part of the collections at the Canadian Museum of Nature. Here I am holding part of the frill of Chasmosaurus belli. Image: Dan Smythe © Canadian Museum of Nature

There are many scientific subtleties on the stamps that I hope won’t go undetected. Did you notice that the Ornithomimus has wings? Or that the Tylosaurus has a tail fluke? Or that the nostril of the Chasmosaurus is positioned forward on its face, as opposed to back towards its nasal horn? These are all scientific findings that have only come to light in recent years.

Of course, my work as scientific advisor was made easy by collaborating with one of the most renowned palaeo-artists in the world, Julius Csotonyi. Julius’ sharp eye and aesthetic sense do justice to these great beasts in a way that simple scientific descriptions never could, and I would be remiss if I didn’t pay him tribute.

Designer Andrew Perro is likewise deserving of accolades for his well-executed contribution. How much more realistic do those dinosaurs appear popping out at you from those stamps? It’s as if the badlands in the background (expertly photographed by Judy Arndt) have given up their deathly grip so that the dinosaurs (and one mosasaur!) could burst forward with life once again.

One of the perks about being a palaeontologist with the museum is the chance to do advisory work like this, but working with Canada Post and the associated talent has made this project stand out for me. I even got to promote the stamps last week on the national TV morning show, Canada AM! If you’d like a set of your own stamps, they’re available for purchase now in the gift shop at the Canadian Museum of Nature, or of course, at Canada Post outlets.

Jordan standing with Canada AM anchor Marcia MacMillan and stamp designer Andrew Perro.

Here I am with Canada AM anchor Marcia MacMillan and stamp designer Andrew Perro (right). Image: Andrew Perro © Canada Post

NOTE: On Thursday, April 16 at 6:30 p.m. celebrate this new stamp series at the museum. Meet Dr. Jordan Mallon and palaeo-artist Julius Csotonyi. Hear how science and art bring to life the five creatures portrayed on the stamps. See large reproductions of each stamp and real fossils that match the featured animals. Stamps will be available for purchase.

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Preparing Diatom Samples: Part 2

Read Part 1, in which Joe Holmes provides an introduction to diatoms—what these microscopic organisms are and their importance.

Upon my arrival in early 2013 as a volunteer in the phycology lab of the Canadian Museum of Nature in Gatineau, Quebec, I learned on the job how to prepare diatom specimens for storage and microscopic study.

An array of diatoms.

Several diatom species, seen through an SEM microscope. Image: Paul Hamilton © Canadian Museum of Nature

Because of all the steps and time involved, processing an individual sample—starting with a dried field sample and ending with it mounted on a microscope slide—may take two days. However, because there are usually dozens of samples to work on, they are processed together in groups of 12. Processing a box of 100 or more may take a week of full-time work, or a couple of months part-time (my speed at one day a week).

Acid Shell Cleaning

The first thing we do when receiving a sample is clean the microscopic shells (valves) of the diatoms of any lingering organic material, much like cleaning out a seashell.

From each sample (wet or dry), material containing thousands to millions of diatoms is added to a glass beaker and marked with the sample’s collection reference number. Powder-like dry material is scraped off filter paper from inside the sample bottles. Twelve samples are normally processed together as a group.

Beakers and bottles on a counter.

Beakers with dry material from sample bottles. Image: Joe Holmes © Canadian Museum of Nature

A small amount of acid mix is carefully squirted into each beaker and boiled on a hotplate for 25–30 minutes at high temperature. Afterwards, the beakers are allowed to cool for 15–20 minutes before the centrifuge process is started. Boiling in acid dissolves and separates diatoms and other organic matter, leaving the cleaned diatom shells, which are made of silica. The remaining particulates are like small pebbles and clay.

Equipment under a fume hood.

Acid-dispensing bottle and heater with boiling beakers. Image: Joe Holmes © Canadian Museum of Nature

Centrifuging Water Mixture

To separate the diatoms from other material, we use a series of deionized water dilutions. (Deionized water has had most of its mineral impurities removed).

Each boiled beaker mix is poured into a corresponding plastic centrifuge tube marked with the sample’s reference number. The tube is then filled within a centimetre of the top with deionized water.

The tubes are placed in a centrifuge and run at 3000 revolutions per minute for 10 minutes, the objective being to force the diatoms down into the cone-shaped bottom of the tube.

A look under the lid of a centrifuge.

Centrifuge with 12 tubes ready to run. Image: Joe Holmes © Canadian Museum of Nature

Once done, most of the liquid mix is removed using a narrow hose attached to a siphoning pump, leaving diatoms and some liquid at the bottom of the tube.

Tubes are then refilled with fresh deionized water and the centrifuge/siphoning/refill procedure is repeated five times to increasingly purify the diatom mix.

After the final run/siphoning, the remnant “button” of diatoms and remaining liquid are shaken from the bottom and poured into a new sample bottle. A metal scraper is often required to get at all the lingering material if it is sticking to the bottom. Lids are labelled with the corresponding reference number.

Each final sample bottle should be about a quarter full of the diatom/water mix. Bottles are placed in boxes of 100 and into cabinet drawers in the wet collection to await microscope-slide creation.

Personal protection is required during the above stages. I wear special neoprene rubber gloves and a face visor when handling any acids. Acid boiling is done under a fume hood that removes toxic vapours. For centrifuge and siphoning work, I use latex gloves. Waste water is disposed of in an environmentally safe manner.

A man wearing protective gear stands in a laboratory.

Joe Holmes working at a fume hood in the lab. Image: Paul Hamilton © Canadian Museum of Nature

Making Light-Microscope Slides

Light microscopes can magnify up to 1600 times and are used to look straight into the layers of diatoms based on fine focusing.

To create the glass slides of diatom samples for use in the microscope, the required samples are selected from the museum’s wet collection. A slide-warming table is laid out with small glass cover-slip blanks corresponding to the sample bottles to be processed. A drop of deionized water is added to each cover slip using a micropipette.

Each sample bottle is gently shaken to better mix the water with diatoms, and then two to three drops of the sample are added to its corresponding cover slip. The same micropipette is cleaned with deionized water between samples to avoid cross contamination.

Cover slips are allowed to dry, leaving a dried diatom smudge on each one.

Glass slide blanks are prepared for each cover slip by recording their reference number on the label portion of the slide (with a pen, label sticker or etching tool).

Next, we need to permanently “glue” the cover slip on top of the glass slide. To do this, a mountant (of similar colour and viscosity as honey) is used to fix each cover slip to its corresponding slide. The museum uses either Naphrax or Hyrax.

One at a time, each slide is heated on a hotplate at 300°C for three to four seconds. A drop of mountant is added to the slide using a glass rod. The corresponding cover slip (smudge side down) is attached to the bubbling mountant using tweezers. Using a small metal tool, air bubbles are gently forced out of the cover slip to make a tight fit with the slide.

Slides are allowed to cool for at least 15 minutes. Excess mountant is scraped off with a razor blade and then cleaned off with a damp cloth.

Once completed, the slides are ready to use under the microscope and can be filed in the museum diatom slide collection by reference number in wooden cabinets with thin metal drawers that hold 20 slides each.

An open cabinet with one drawer pulled out.

A cabinet for filing glass slides. Image: Joe Holmes © Canadian Museum of Nature

Making SEM Discs

A machine called an SEM is used for looking at precise details within diatom. It can magnify up to 100 000 times, but the magnification that we generally use for diatoms is up to 20 000x.

For preparing samples to be viewed by the SEM, a different procedure is used from that for light microscopes. Samples from the wet collection are dried on small pieces of aluminum foil that are then placed on metal discs, rather than drying them on cover slips.

To examine the sample in the SEM, further processing using a vacuum process must be done to apply an ultrathin amount of gold as a conductive coating before a sample disc is ready to use.

Because of the use of gold and initial equipment costs, the SEM is more expensive to use than light microscopes (which the museum has many of).

Data Storage

With both the light microscope and SEM, we have special cameras and software to take diatom photos.

The photos and specimen data are then copied into the museum’s phycology collection database, which is publicly accessible online.

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Preparing Diatom Samples: Part 1

After a career of almost 33 years in IT, I started volunteering at the Canadian Museum of Nature in January 2013. From my time as a youth, I had always had a keen interest in science and I was looking for something meaningful to keep me busy once a week. The Museum of Nature was a good fit.

In a weird coincidence, I was assigned to Paul Hamilton, who was in fact a former classmate from the 1970s at Laurentian High School in Ottawa. Paul is now a Senior Research Assistant in botany at the museum. He curates Canada’s Algae Collection and studies the biodiversity of microscopic life.

A man wearing protective gear stands in a laboratory.

Joe Holmes working at a fume hood in the lab. Image: Paul Hamilton © Canadian Museum of Nature

Working with Paul in the diatom lab, I have so far done a variety of jobs related to diatom preparation and observation. For a while I created slides from prepared samples, then did some work photographing microscopic specimens. Lately, I have been preparing samples from specimens taken from the field. The process of field collection, preparation, filing and study of diatom samples is quite involved and never ending, and not many are aware of the skill, complexity and intricacies of the process.

Phycology Collection and Diatoms

The Canadian Museum of Nature maintains an ever-growing algae (phycology) collection of over 110 000 samples. It contains everything from large seaweeds to small microscopic diatoms.

An array of diatoms.

Several diatom species, seen through an SEM microscope. Image: Paul Hamilton © Canadian Museum of Nature

Diatoms are a group of microscopic algae encased in a shell-like silica wall. There are over 15 000 documented species, most of which are 50 microns or less in length (a micron is one millionth of a metre).

In the environment, diatoms produce energy and free up oxygen in the process. Conservative estimates suggest that diatoms, in combination with other algae, can contribute up to 20% of global energy. These organisms are at the base of the food web, producing energy that is passed through their body to small life forms and progressing along the web to invertebrates, fish and ultimately, large mammals like whales.

Besides their importance to the environment and despite their small size, I have discovered through microscopes and photos in books that diatoms have very intricate, complex and beautiful structures, from round and oval to long, thin and even boat-like shapes. In my opinion, the beauty and wide variety of diatom shells has certainly contributed to the popularity of collecting and studying these organisms.

In the lab, we use diatoms as life indicators for researching climate change, climate history in the Arctic, water quality, evolution and single-cell DNA sequencing and analysis. In industry, they have even been used in products like mild abrasive in tooth paste and environmentally friendly insecticides for gardening (where the sharp silica shells can cut, and block insect movement).

A diatom.

A live diatom (Gyrosigma acuminate) under a light microscope at 1000x. Image: Paul Hamilton © Canadian Museum of Nature

The diatom specimens in the national collection come from across Canada and around the world. Samples are collected in the field by museum scientists or received as donations from other scientific institutions. Data on each sample, such as date, location found and photographs of diatoms within it are kept in the phycology collection database.

At the moment in the museum lab, Paul has had us process and study samples from Ungava in Northern Quebec, Haliburton Highlands in Ontario, Adirondack Park in New York State, U.S.A., Bolivia in South America, the Canadian Arctic Archipelago and Franz Josef Land in Arctic Russia. We have also photographed previously prepared slides from Lake Te Anau in New Zealand.

Obtaining Samples from the Field

Freshwater diatoms can be collected from all wet environments, like ponds, lakes, ditches and rivers. It is easy to collect diatom samples from bottom mud and sediments using a tool like a turkey baster, or from plain water. Samples can be dried in the field on filter paper or transferred wet into small bottles.

A note is made for each sample as to the exact location of where it was taken, latitude and longitude, along with who collected the sample and the date.

A bank of cabinets with a couple of open drawers.

Cabinet drawers with boxes containing sample bottles. Image: Joe Holmes © Canadian Museum of Nature

Upon returning to the lab, a reference number is assigned to each sample bottle based on available catalogue numbers. Corresponding sample data are registered in the museum’s phycology database, and additional data such as photographs are added later.

Bottles are sorted and placed within boxes of 100 for storage in the diatom collection cabinets awaiting the next processing step. Progress is recorded in a lab notebook to ensure proper procedure is followed and to carry on at a later date.

Samples can be in a variety of states:

  • Alive—raw samples from the field kept alive for a limited time to observe the organisms in their natural state and for DNA sequencing
  • Dry—as received from the field or after freeze drying.
  • Wet—preserved after cleaning and processing where all organic material has been removed, leaving only the silica diatom shells in a water solution
  • Slides—the final stage:
    • glass slides for light-microscope study
    • aluminum discs for SEM study.

Read my next blog article for more detail about preparing samples and making slides.

Posted in Collections, Plants and Algae, Tools of the trade | Tagged | 1 Comment

Can the Arctic Steal the Show on International Colour Day?

If I asked you to close your eyes and picture the Arctic, what would you see? White expanses of driven snow? Grey rock and pale blue ice? Yellow green ribbons of light dancing in the night sky? It’s true that our Northern territories are iconic for their vast, beautifully bleak scenes, but you don’t have to walk very far across the tundra (or through our Arctic Voices exhibition), to discover that the Arctic is anything but grey-scale.

Collage: Flowering plants arranged to form a rainbow of colour.

The flora of the Canadian Arctic spans the rainbow – Arctic summers are an explosion of colour across the tundra. Images: Paul Sokoloff © Canadian Museum of Nature

March 21 marks International Color Day in nearly 30 countries worldwide—a day set aside to raise awareness and to celebrate the perception of colour. Given the frigid snowy winter that we’ve been having here in Ottawa (and across much of eastern Canada), it’s hard to look out the window and imagine (as one might about the Arctic) anything but a grey and frigid world. But both here and in the Arctic, that chilly white milieu will spring forth with unexpected colours as winter gives way to spring’s thaw.

Ground-level view of flowers with tents in the background.

Blue and orange are complementary to each other— if you keep that in mind you’ll notice that they’re used together everywhere from print advertising to movies. Naturally I couldn’t resist snapping shots of these sea-blue Arctic lupines (Lupinus arcticus) juxtaposed against our high-visibility orange tents. Image: Paul Sokoloff © Canadian Museum of Nature

True, the Arctic summer is brief, but the hardy plants that live there tend to get straight to the point. Flowers are reproductive organs after all, and if you have only a few short months to get in on, you’d better strut your stuff.

A flowery foreground overlooks a river.

Colourful purple swathes of alpine milkvetch (Hedysarum alpinum) carpet the hillsides along the banks of the Coppermine River, Nunavut. Image: Paul Sokoloff © Canadian Museum of Nature

Bright mauve patches of purple mountain saxifrage herald the arrival of spring across much of the Arctic, oftentimes beginning to bloom while there’s plenty of snow left on the ground. These ephemeral blossoms don’t stick around long, and soon the Arctic will transition to the green lushness of full summer.

Many white flowers seen from the side.

The flowers of the white arctic mountain heather (Cassiope tetragona) protrude from north-facing snow beds like delicate white bells. Image: Paul Sokoloff © Canadian Museum of Nature

Yellow poppies blowing in the breeze, orange lichens plastered over boulders, the delicate pink bells of bog rosemary and curvy purple petals of louseworts. Come autumn, this rainbow will be replaced by fields upon fields of orange red bearberry leaves, just as trees down south change colour before winter’s inevitable return.

A beached boat rests in front of several small white buildings.

The red boat in front of the old Hudson’s Bay trading post is an iconic Iqaluit scene; the White Stripes even filmed a music video here. Image: Paul Sokoloff © Canadian Museum of Nature

Of course, plants aren’t the only colour to be found in Nunavut and the Northwest Territories. Walk through any community and you’ll be struck the by multi-coloured houses the beautiful arts and handicrafts. Northern animals, vegetables, minerals—all are a visual treat worthy of celebrating.

A man squats to look at blue stones on the ground.

Museum botanist Jeff Saarela, Ph.D., inspects blue-speckled lapis lazuli along the Soper River, Nunavut. Image: Paul Sokoloff © Canadian Museum of Nature

So if you’re feeling inspired to seek out the colours of the North, our Arctic Voices exhibition runs until May 3.

In the meantime, Happy International Colour Day!

A flowering plant nestles among rocks.

Even in the bleakest Arctic deserts, pops of colour, like this purple mountain saxifrage (Saxifraga oppositifolia) can be found peeking through the grey. Image: Paul Sokoloff © Canadian Museum of Nature

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Jawing about Dinosaurs: What the Herbivore’s Jaws Are Telling Us

One of the great things about working at a museum is having access to the vast collections of fossils that reside behind the scenes. These aren’t regularly seen by the public (our annual Open House excluded), but they nevertheless serve an important role in my research. I recently published just such a study in the Journal of Vertebrate Paleontology with my former Ph.D. supervisor, Dr. Jason Anderson, that draws heavily upon specimens in the collections of the Canadian Museum of Nature and elsewhere.

Panoramic view of shelving ranges containing dinosaur fossils.

A view of our vast fossil collections. Image: Jordan Mallon © Canadian Museum of Nature

We were curious to know what role, if any, differences in jaw mechanics may have played to allow plant-eating dinosaurs to co-exist in Alberta 75 million years ago.

We know today, for example, that the high diversity of finch species in the Galápagos Islands is made possible by their diverse jaw arrangements. Species that eat the largest, hardest seeds have larger jaw muscles that are situated further forward on the beak, giving those species the extra leverage needed to crack open such massive seeds. In this way, an ecosystem can support a rich diversity of species because they are not all competing for the same types of food.

We figured that maybe similar principles allowed for the rich diversity of plant-eating dinosaurs in Alberta during the Late Cretaceous Period.

It can be difficult to know about muscle size in the fossil record because these soft tissues do not normally fossilize. We can, however, know something about how the jaw muscles were arranged because they leave distinctive marks on the skull bones where they attach. Therefore, by carefully measuring the attachment sites of the different jaw muscles, we can come up with complex lever models of the lower jaw that allow us to compare bite leverage across numerous species.

Three diagrams of dinosaur skulls in lateral view; one diagram in lateral view of a lower jaw.

Jaw muscle reconstructions for an ankylosaur (A), a ceratopsid (B) and a hadrosaur (C). The lever model we used is depicted at right (D). Image: © Journal of Vertebrate Paleontology

What did we find? It seems that the jaws of the duck-billed hadrosaurs and horned ceratopsids were constructed in such a way as to produce a very high leverage, giving them an especially powerful bite. The armoured ankylosaurs, on the other hand, had comparatively weak jaws.

Within each of these groups, bite forces do not appear to have varied by much; different species of hadrosaurs had jaws that worked in very similar ways, as did different species of ceratopsids. The jaws of different ankylosaur species were slightly more variable, suggesting that there may have been some variability in their diets, too.

The take-home message is that, while there were certainly some differences in jaw mechanics between the major groups of plant-eating dinosaurs, we don’t see the same subtle differences between closely related species within those groups as we see in today’s Galápagos finches.

This tells us that the Albertan plant-eating dinosaur communities operated in a slightly different way, and that perhaps differences in other aspects of their anatomy allowed these animals to exploit different food sources to coexist.

Some of my previous work suggests that this is the case—we do see many differences in skull and beak shapes, feeding heights and tooth wear, even among closely related species. These insights tell us something about what it takes to support a diverse ecosystem over long periods of time—something that concerns conservationists today. It’s amazing what can be learned by plumbing the depths of our vast collections!

Read an abstract of the article:

Posted in Collections, Fossils, Research | Tagged , , | 2 Comments

Basalt: A Source of Beauty and Wonder

Further adventures of our mineralogists in Cambodia: follow museum scientists Paula Piilonen and Glenn Poirier on their hunt for minerals for their research.

In Ratanakiri province, and many other regions across Cambodia, the land is covered by a dark orange red, iron- and aluminum-rich soil called laterite.

Images: A red dirt country road; a look down at a red-dirt encrusted boot.

Laterite dust covers all the roads in the region! Laterite dust turns all your clothes red. Some days it’s hard to tell if I am tanned or simply dirty! ☺ Images: Paula Piilonen © Canadian Museum of Nature

Laterites form in tropical climates and are the result of extensive, intense chemical weathering of the underlying rock—in this case, basalt.

Basalt forming a round shape in the ground beside a geologist's hammer.

In situ weathering (spallation) of basalt to form laterite. Image: Paula Piilonen © Canadian Museum of Nature

When wet, laterite can be cut into blocks and used for construction of buildings. As it dries, it hardens to a rock-like consistency. The Angkor Wat complex, along with many other temples of Angkorian age (9th and 10th centuries) found throughout both Cambodia and Thailand, have been constructed with laterite bricks as the main foundation, covered with more aesthetic sandstone facing.

Carved stone structures at an ancient temple.

Laterite bricks form the internal foundation of Banteay Srei temple, 23 km north of Angkor Wat (10th century). Image: Paula Piilonen © Canadian Museum of Nature

Because laterite profiles in this part of the country can be up to 50 metres thick, it is sometimes difficult to find fresh, solid rock outcrop. For this reason, our field work tends to focus on areas that provide the most likely exposure: waterfalls, rivers/creeks, boulder fields at the bottom of slopes, and quarries.

A woman stands near a small waterfall.

Paula Piilonen at the Katieng Waterfall, Ratanakiri province, Cambodia. The waterfall goes over a basalt flow. Image: Glenn Poirier © Canadian Museum of Nature

Today we visited one such quarry north of Ban Lung and the Angkor Gold office. Here, they are quarrying basalt, the rock that we are studying, for use as road fill. After poking around the waste-rock piles on the edges of the quarry near the stone crushers, we met one of the workers who, through hand gestures because he didn’t speak English and we don’t speak Khmer, told us that we could enter into the quarry itself.

An uneven landscape with machinery.

Basalt quarry 4 km north in Ban Lung, Ratanakiri province, Cambodia. Image: Paula Piilonen © Canadian Museum of Nature

At the bottom of the quarry, we made a startling discovery. Although the larger blocks are drilled off and pushed to the bottom of the quarry (explosives are not allowed here), the bulk of the work to reduce the boulders to smaller fragments (about 30 cm to 60 cm) was being done BY HAND. Workers (in flip flops) stand in the rock piles and split boulders using only a large sledgehammer. A full shift of this manual labour must be back-breaking.

The smaller fragments are then loaded into a dump truck and fed into the crushers at the top of the quarry, where they are reduced to road fill (15 cm to 30 cm).

Images: A man uses a sledgehammer among piles of rocks; machines make piles of crushed rock.

Left: A quarry worker splits basalt, his only tool a sledgehammer. The fruit of his labour is further crushed by machines, at right. Images: Paula Piilonen © Canadian Museum of Nature

The quarry itself was an amazing experience for a geologist: a textbook-quality volcanic section consisting of three distinct basalt flows. Having access to the quarry wall to study (and sample) this section adds important information to our study of the basalts in the region. Nowhere else can multiple, fresh flows be observed in a single locality.

Images: A man stands beside a rock wall; lines demarcating three basalt layers have been applied to a photo (Top: Vesicular columnar 1.5 m, Middle: massive columnar 40 cm wide, Bottom: massive columnar 1.5 m wide).

Glenn Poirier examines a large (1.5 m wide) basalt column at the bottom of the quarry. Three distinct basalt flows can be identified. Images: Paula Piilonen © Canadian Museum of Nature

We were able to collect 15 kg of rock and leave the quarry satisfied with an excellent morning of work.

Posted in Fieldwork, Research, Rocks and minerals | Tagged , , , | Leave a comment