Two Rare Species, One Big Trip

A researcher standing on the tundra and holding a plant specimen

During a search for the endangered hairy braya on Baillie Island, Northwest Territories, researcher Lianna Teeter holds a specimen of a related member of the genus Braya. Image: Paul C. Sokoloff © Canadian Museum of Nature.

“Is this it?” asks Lianna Teeter, a researcher from Fisheries and Oceans Canada’s Institute of Ocean Sciences in Victoria. In her hand she holds a small braya, an Arctic plant in the mustard family.

On this September day, we’re towards the end of the 11th leg of the historic Canada C3 expedition to celebrate Canada’s 150th anniversary. Our leg’s group, approximately 60 Canadians from across the country, is part of this coast-to-coast-to-coast ocean journey of reconciliation, unity, diversity, and science.

A small team of us have landed and are searching for an endangered plant species, the hairy braya (Braya pilosa).

“Close, but not quite,” I reply to Lianna. The specimen she found, a different species of Braya, still goes into a plastic bag that we’ll take back to our ship, the Polar Prince, for pressing.

Polar-Prince-in-Sutton-Bay-DSC_0169-PSokoloff-2017

The Canada C3 expedition vessel, the M/V Polar Prince, holding station in a bay on Sutton Island, Nunavut. Image: Paul C. Sokoloff © Canadian Museum of Nature.

Our search team, a handful of expedition scientists and other participants, goes back to exploring the muddy plateaus of Baillie Island, just off the tip of Cape Bathurst on the Northwest Territories mainland.

This is the only place on the planet the hairy braya is known to exist, but we don’t find it that day.

We do however witness the dramatic erosion of the shoreline into the sea, a stark reminder of the rapid climate change that is threatening species, and a way of life, across Inuit Nunangat, the Inuit homeland.

erosion

Erosion on Herschel Island. Image: Richard Gordon © Government of Yukon

However, just the day before our hairy braya search, we did find a different rare species near the tip of Cape Parry, the peninsula immediately to the east of Cape Bathurst.

Just over the hill from our landing spot, growing in cracks spreading across the mud, we found the Arctic orangebush lichen (Teloschistes arcticus).

Teloschistes_arcticus_1201_DSC_0400_PSokoloff_2017

The Arctic orangebush lichen (Teloschistes arcticus) growing on Cape Parry, Northwest Territories. Image: Paul C. Sokoloff © Canadian Museum of Nature.

This rare lichen is known in Canada only from this particular area in the Northwest Territories.

The specimen we take for the Canadian Museum of Nature’s collection will document the species’ existence in the Canadian Arctic in 2017, just as all the botanical collections made on C3 will serve as part of a scientific legacy for this epic voyage.

A purple flower among rocks and lichen

A late-flowering Arctic locoweed (Oxytropis arctica) gives the tundra a pop of purple. Image: Paul C. Sokoloff © Canadian Museum of Nature.

Quanaqqutit to our amazing hosts in Nunavut and the Inuvialuit Settlement Region!

Posted in Collections, Plants and Algae, Research, Arctic, Botany, Species Discovery and Change | Tagged , | 2 Comments

Small pond holds big fish diversity, and drama

Some of the smallest bodies of water, such as a pond, can contain an unexpectedly high number of different species of fishes, the most diverse of all vertebrate animals.

At the Canadian Museum of Nature’s research facility, there’s a naturally populated pond — about the size of an Olympic-size swimming pool — which surprisingly is home to 15 species of fishes. By comparison, the museum’s little pond has almost a fifth of the species found in the entire Ottawa River watershed, which has about 80 fish species.

Aerial view of the museum’s research and collection facility. Inset: a woman standing in the pond.

It’s a small pond. The museum’s research facility is the large, white roofed, rectangular building in lower, centre-left. The pond is in front of it. In the inset, Emma Lehmberg, a museum summer student, collecting specimens in the pond. Aerial photo: Chuck Clark, © Chuck Clark. Inset: Cassandra Robillard, © Canadian Museum of Nature.

Of these fishes, eight species belong to the minnow family (Cyprinidae). Although often overlooked because they’re small, minnows have fascinating behaviours.

For example, the Golden shiner (Notemigonus crysoleucas) will sometimes lay its eggs in the nest of one of its natural predators, such as the Largemouth bass (Micropterus salmoides). Although this may seem dangerous, it benefits the Golden shiner because the Largemouth bass defends its nest from egg poachers, inadvertently protecting the Golden shiner’s eggs.

A Fathead minnow fish

A male Fathead minnow (Pimephales promelas) with prominent breeding tubercles. Image: Shalini Chaudhary, © Canadian Museum of Nature.

The Fathead minnow (Pimephales promelas), another minnow species found in the pond, displays a dramatic physical change in the breeding season. Bony tubercles grow on the male’s head, which also darkens. The male will guard the eggs lain by its mate and drive off other fishes, sometimes even his mate!

A Pumpkinseed fish

The Pumpkinseed (Lepomis gibbosus) has markings and colouration that rival tropical fishes. Image: Emma Lehmberg, © Canadian Museum of Nature.

A more familiar fish in the pond, especially to novice anglers, is the Pumpkinseed (Lepomis gibbosus). It’s one of the most colourful of local fishes and is found throughout North America. Did you know that depending on the prey available in a given body of water, the Pumpkinseed will have different body part shapes and structures? For example, Pumpkinseeds in waters with large shelled prey, such as snails, have stronger jaw muscles and crushing bone parts in their mouths than Pumpkinseeds in ponds without these molluscs.

Bullhead

A Brown bullhead (Ameiurus nebulosus) with its barbels fully extended to sense its aquarium environment. Image: Francesco Janzen, © Canadian Museum of Nature.

Lastly, the museum’s little pond is home to the Brown bullhead (Ameiurus nebulosus), a common catfish.

Brown bullheads, and catfish generally, have facial taste receptors with a high concentration of them on their whiskers, or barbels. This, along with its keen sense of smell, enables the bullhead to detect food in its murky habitat where visibility is poor.

Even more amazing is the fact that bullheads and other catfishes have specialized receptors embedded in their skin that can detect electricity. This includes the minute electrical activity produced by the contracting muscles of a swimming minnow, which could lead the Brown bullhead straight to its next meal.

It may be a small pond, but the fish stories it holds are truly remarkable.

Table listing the common names and species names of the fishes found in the pond.

A list of the 15 species found in the pond at the museum’s research facility. Eight species are from the minnow family, the bass and sunfish family has two representatives, and all other species are the sole members of their respective families. © Canadian Museum of Nature.

 

Posted in Animals, Nature Inspiration, Water | Tagged , , | Leave a comment

Moss and Lichen: Wait, what’s the difference?

I love talking to the public about mosses and lichens. The two are intricate, fascinating, and underappreciated. But a common question I get is: Wait… what’s the difference between moss and lichen?

Lichen on a tree

Oak Moss, Evernia prunastri, is actually a lichen. Image: R. Troy McMullin © Canadian Museum of Nature

It’s no wonder that people confuse the two groups. Historically, the term “moss” has often also been applied to lichens. After all, they are both small things that grow in shaded places and resemble neither a mushroom nor a vascular plant. They are both also cryptogams, meaning they reproduce without seeds or flowers.

So, what’s the difference? In short, a moss is a simple plant, and a lichen is a fungi-algae sandwich.

Mosses are multicellular organisms with leaflets made of photosynthetic cells, just as with trees, ferns and wildflowers.

But unlike these vascular plants, mosses don’t have specialized tissues that actively transport water and nutrients, such as sap, from the ground to the leaf tips, and vice-versa.

Instead, like a leafy, green sponge, mosses simply absorb water and nutrients. This means they can’t grow too tall or they risk drying out at the top.

A collage of mosses.

Mosses come in many different forms. They are usually green, except for a few species that are yellow, brown, or purple. Image: Cassandra Robillard, © Cassandra Robillard

Lichens, conversely, are a mix of at least two different organisms, a fungus and alga, living together as one.

In the simplest case, a fungus surrounds a colony of algae. The algal cells provide food for the fungus via photosynthesis, while the fungal partner protects the algae from drying out and sun damage.

When wet, the algae become visible through the top fungal layer, giving the lichen a green colour that can resemble moss. But when dry, lichens are rarely green, and instead come in many vibrant colours. Lichens also have diverse growth forms, but lack leaves of any kind, which helps to tell them apart from mosses.

(As an aside, liverworts, which are related to mosses, sometimes resemble wet lichens, but never mind that for now!)

A collage of lichens

Lichens come in a wide variety of forms and colours. Cassandra Robillard, © Cassandra Robillard.

So, do you think you can distinguish a lichen from a moss?

The only way to know is to test yourself and go looking for them in a backyard or park near you!

Lichen and moss on a branch

Can you see the difference between the lichen and the moss on this branch? Image: Cassandra Robillard, © Cassandra Robillard.

Posted in Botany, Plants and Algae, Uncategorized | Tagged , , , | 1 Comment

Hunting for Mammal Fossils in Grasslands National Park

Grasslands National Park in southern Saskatchewan is well known for its rolling hills, breathtaking badlands, and inquisitive prairie dogs. One sign instructs visitors to “shoo the prairie dogs away with enthusiasm”. But the park is also one of the best places in the world to understand how this little mammal, and all its furry mammalian relatives, came to replace the dinosaurs.

A panoramic view of the badlands in Grasslands National Park

A view of the badlands in the East Block of Grasslands National Park. In the summer of 2017, a Canadian Museum of Nature-led team made its first foray into this area to scout for promising exposures of fossil-bearing rocks. Image: Danielle Fraser © Canadian Museum of Nature

That’s because the park is rich in fossils that tell us of the dramatic environmental and faunal changes that have occurred since the extinction of the dinosaurs.

This past summer, I led a small team of intrepid female palaeontologists exploring the park as part of my research into the evolution of mammals.

Five researchers posing for a photo in Grasslands National Park

The museum’s 2017 extinct mammals prospecting team, from left to right: Carleton University student Brigid Christison, museum technician Margaret Currie, museum research scientist Danielle Fraser, and University of Calgary student Abigail Hall. Far right is Emily Bamforth, a curatorial assistant at the T. Rex Discovery Centre in East End, Saskatchewan. Emily kindly provided an overview of the stratigraphy and topography of the East Block at the start of the fieldwork. Image: Joshua Erikson, © Joshua Erikson

Wherever we went in the East Block (the park is divided into separate eastern and western chunks), it was difficult to miss the coal seam that marks the Cretaceous-Paleogene Boundary (KPg), the end of the dinosaurs and the beginning of the age of mammals, about 66 million years old. At times we literally tripped over the moment in time that dinosaurs went extinct.

A close-up view of the coal seam in the earth

A small exposure of the coal seam that marks the Cretaceous-Paleogene Boundary (KPg) and the extinction of the dinosaurs. Image: Danielle Fraser, © Canadian Museum of Nature

The rocks at the KPg boundary record an environment much more tropical than modern Saskatchewan and a mammal fauna very different from today.

On the very top of the hills, we uncovered the first 20 million-year-old fossil sites ever found in the park. These much younger rocks record an environment that would have looked more familiar to us today, with a mix of forest and grassland. It was an environment populated by a variety of mammals with hooves, including three-toed horses, rhinoceroses (yes, rhinos!), and relatives of the living pronghorn.

A hill in Grasslands National Park

The museum team prospects for fossils on a hill of post- Cretaceous-Paleogene Boundary (KPg) rocks. Next summer, museum researcher Danielle Fraser will continue searching as part of a multi-year project to recover and describe the fossil mammals of Grasslands National Park. Image: Danielle Fraser, © Canadian Museum of Nature.

On future expeditions to Grasslands National Park we will continue to search the rocks immediately after the KPg for fossils of early primate-like mammals (Plesiadapiformes) and other extinct mammal lineages.

Plesiadapis model and tooth of a three-toed fossil horse

Left: A model of the extinct early mammal, Plesiadapis. About the size of a squirrel, this little mammal belongs to an extinct group that’s perhaps ancestral to primates, including humans. Image: M. De Stefano, © MUSE-Museo delle Scienze (CC BY-SA 3.0). 
Right: Covered in lichen, the tooth of a three-toed fossil horse. This fossil likely represents a member of the genus Archaeohippus, a small horse, about the weight of a medium-sized dog, that lived about 20 million years ago. Field number: GNP2017-WM2-18-1. Image: Brigid Christison, © Canadian Museum of Nature.

In comparing such specimens with fossils from the younger overlying layers we hope to paint a picture of how mammals responded to the extinction of the dinosaurs and to the extreme environmental changes that have occurred over the past 66 million years.

And how this all combined to produce the curious little prairie dogs.

Posted in Fieldwork, Fossils, Mammals | Tagged , , , | Leave a comment

Cracking the mystery of crystal structure

Portrait of the author

Joachim de Fourestier. © Canadian Museum of Nature

This past summer, as the Carleton University Harry Reid Cox Intern at the Canadian Museum of Nature, I worked with museum researcher Aaron Lussier, Ph.D., to identify how common elements, such as silicon and iron, combine to make up the structures of large numbers of minerals.

The ultimate goal of this ongoing research is to determine why certain types of crystal structures are more common than others. Is it because they are more stable, or is it because of other factors?

This is a big question in mineral sciences. Believe it or not, we still don’t really understand why most minerals exist with the shape, form, atomic structures, and chemical compositions that they have.

So, the origins of crystal structure is a huge gap in our understanding of how the Earth system works.

We do know that minerals have fascinating internal crystal structure.

Minerals are made up of atoms that are perfectly ordered, creating crystals. Even a crystal that is big enough to hold in your hand, for example one on display in the museum’s Earth Gallery consists of many trillions of atoms, each and every one arranged in a very precise location.

Interestingly, minerals that look unrelated can share common structural aspects. For instance, they may have silicon atoms arranged in sheets, or aluminum atoms arranged as part of a seemingly infinite chain (See Figure 1).

illustration of mineral structure

Figure 1. Mineral structures are often depicted using closed-form polyhedra with a metal atom at the centre and oxygen atoms at the points. This image shows how chains (a), consisting of edge-sharing octahedra, link to form sheets (b). This type of chain structure is found in more than 50 different natural mineral species, and in dozens of synthetic compounds. Image: Aaron Lussier © Canadian Museum of Nature

If we could answer the question of why minerals have a certain atomic structure, there would be many practical applications.

We could create better synthetic materials with specialized properties. We could engineer materials that interact predictably with local geology, or to aid in environmental remediation of harmful toxins, like lead and mercury, and even for the disposal of radioactive waste.

Just as with the diversity of mineral structures, the possibilities for their application could be endless!

Chromite specimen

A massive chunk of chromite from Tiébaghi, New Caledonia. Chromite is the main source of the metallic element chromium, used in creating stainless steel. Its atomic structure contains fragments of the chains shown in Figure 1. Catalogue # CMNMC 59740. Image: Joachim de Fourestier © Canadian Museum of Nature.

Magnetite specimen

A beautiful specimen from Russia exposing well-formed octahedral crystals of magnetite. Catalogue # CMNMC 85016. Image: Joachim de Fourestier © Canadian Museum of Nature.

Posted in Research, Rocks and minerals, Species Discovery and Change, Uncategorized | Tagged , , | Leave a comment

New Mural Tells a Thousand Collecting Stories

A new mural near the main entrance of the Canadian Museum of Nature’s research campus depicts a spectacularly dense and colourful web of interconnected peoples’ names.

This web is the grand social network of collectors who together have hiked trails, paddled rivers, trudged through bogs, and visited the Far North and other remote places in Canada in search of natural treasures.

A mural showing a network of collectors.

The mural in the lobby of the museum’s research campus on Pink Road in Gatineau, Quebec, reveals the connections between a sampling of the thousands of people who have contributed specimens to the museum’s collections. Image: David P. Shorthouse © Canadian Museum of Nature

Though from a distance the mural appears to be a piece of abstract art, on closer inspection each bubble on the mural is a collector’s name and each line joining names represents the type of museum specimen that links those collectors.

For instance, in 2010 museum botanist Laurie Consaul worked with residents in Sanikiluaq, Nunavut, to document local plant diversity, creating the cluster of names shown below.

close-up of mural showing collectors' names

The collector network formed by museum botanist Laurie Consaul and residents of Sanikiluaq, Nunavut. Image: David. P. Shorthouse © Canadian Museum of Nature.

Museum folk use the term “natural heritage” to describe objects inherited from past generations, maintained in the present and bestowed to future generations. The museum’s research campus houses 14.6 million natural history specimens, from dinosaur fossils to microscopic algae, exquisitely preserved for future generations of Canadians.

Each specimen has a record of its identity, where and when it was collected, and who collected it, information that’s critical for biodiversity science.

Herbarium sheet with a pressed plant

A snow cinquefoil (Potentilla nivea) specimen collected by Laurie Consaul and residents of Sanikiluaq, Nunavut. © Canadian Museum of Nature. Catalogue number: CAN 599404

What the specimen labels don’t fully record is the immense effort required to build and maintain this massive collection, and the intense feelings involved.

The term natural heritage includes a notion of pride, responsibility, and our own identity in relation to Canada’s natural wonders. Your personal heritage may include fond memories of hiking or camping, or attending a bioblitz where an expert helped identify a flitting butterfly or a delicate moss.

Those same feelings of belonging and connectedness are shared by the thousands of collectors who have contributed specimens to the museum.

two people looking at the mural

Teresa Neamtz, a student in the museum’s Scientific Training Program, and lichenologist and Researcher Emeritus Irwin Brodo share an anecdote while examining a network of collectors. Image: Susan Goods © Canadian Museum of Nature.

The mural is fully appreciated if you have the good fortune to view it with a museum staff member during our annual research campus Open House.

As they gaze at the names of fellow collectors, anecdotes of their own collecting trips will begin to bubble to the surface. They will share humorous stories about their trips, tidbits about the specimens and other natural history discoveries.

You too will become connected to the great stories that are part of our natural heritage.

People standing in the river holding nets

Since the early 1970s, herpetologist and museum research associate Frederick W. Schueler (right) has contributed an enormous number of diverse specimens to the museum, from Canadian amphibians and reptiles, to fish, plants and invertebrates. Here, Schueler and colleagues electrofish for lamprey larvae in the Ottawa River, 26 May, 1987. © Canadian Museum of Nature

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Plants 2 Papers: The Sequel

I’ve written in a previous article on how science not communicated (i.e., not published) is science not finished; at the museum this often means telling both the public sphere and the academic world about our findings. While the former may take the form of museum exhibits, public presentations and blogs, the peer-reviewed journal article is still king of the latter.

A sparsely treed landscape.

Our trip to the Coppermine River, Nunavut, took us to the treeline, where white spruces (Picea glauca) dot the transitioning tundra. Image: Paul Sokoloff © Canadian Museum of Nature

Our research group’s latest open-access journal article is a complete, detailed checklist (with lots of colour photos) enumerating the vascular-plant flora of the lower Coppermine River, the focus of our 2014 collecting trip. By combining our over 1200 newly collected specimens with all previously collected specimens in herbaria across Canada, we now know that 300 vascular plant species can be found along this stretch of the river, making it one of the most species-rich areas known on mainland Nunavut.

Coppermine River, Nunavut.

Kugluk (Bloody Falls) Territorial Park, straddling the lower Coppermine River, was found to be floristically rich and diverse. Image: Paul Sokoloff © Canadian Museum of Nature

Many of these new vascular plant records (56) are range extensions, which expand upon previous work and establish new native ranges for these plants.

Seven species are newly recorded for mainland Nunavut, and 14 additional species are recorded for the first time ever in the territory itself.

Composite: Three plants in situ.

New plant records documented in this paper include Carex gynocrates (top left, new to mainland Nunavut), Allium schoenoprasum (right, new to Nunavut), and Botrychium tunux (bottom left, new to Nunavut). Image: Paul Sokoloff © Canadian Museum of Nature

Notably, we found 207 vascular plant taxa (species, subspecies and varieties) in Kugluk (Bloody Falls) Territorial Park, just south of Kugluktuk. This park, set aside for recreation and preservation because of its long, and sometimes bloody, history, can also be considered an important protected area for native vascular plants in the low Arctic.

Composite: Three plants in situ.

Other noteworthy records for Nunavut include Carex capitata (left, new to Nunavut), Cryptogramma stelleri (top right, new to mainland Nunavut), and Eremogone capillaris subsp. capillaris (bottom right, new to Nunavut). Image: Paul Sokoloff © Canadian Museum of Nature

Now that the paper has been published, the data and interpretation contained in this new contribution are out in the world for other scientists to read, reference, cite and (hopefully) use in the field.

The project may be over, but the specimens that we collected and the knowledge that we collated will be useful for decades to come. And as the Arctic field seasons go by, the museum’s botany team will continue to press plants, peer into microscopes, sequence DNA, publish results and widely share our findings for the benefit of everyone who wants to know.

After all, the museum’s collections and knowledge isn’t ours, it’s yours.

A man looks out of a helicopter window.

Jeff Saarela, Ph.D., our expedition leader and the lead author of the subsequent study, surveying the tundra for plant-rich helicopter landing sites. As the director of the museum’s Centre for Arctic Knowledge and Exploration, Jeff continues the museum’s tradition of excellence in Arctic research. Image: Paul Sokoloff © Canadian Museum of Nature

Posted in Arctic, Plants and Algae, Research | Tagged , , | 3 Comments

Pilgrim’s Progress: Sampling Diatoms in the Holy Land

In November 2016, my brother Russell and I had an excellent two-week journey to the Holy Land, visiting Israel, Palestine and Egypt. It was also an opportunity to sample Middle East (ME) freshwater diatoms for the Canadian Museum of Nature’s collection.

Diatoms are microscopic, one-celled algae with a silica shell. Found in sediments, they produce energy and oxygen for organisms in the food web. Scientists use them to study climate change and water quality. For sampling in Israel, I had a sediment-collection permit for various Nature Reserves.

Collage

Israel:
• Top left: Old City of Jerusalem
• Top right: Jesus’ birthplace in the Church of the Nativity, Bethlehem
• Bottom left: The author on Mount Carmel, Haifa
• Bottom right: Fortress of Masada.
Images: Joe Holmes © Canadian Museum of Nature

Trip Summary
Our tour saw Jerusalem, Bethlehem, Qumran, Masada, the Dead Sea, and Tiberias on Lake Kinneret (Sea of Galilee). Then we saw the Jordan River, Haifa, Tel Dan, Nazareth, Caesarea, Tel Aviv, the Negev and Eilat.

In Egypt, we proceeded to Mount Sinai, Sharm El-Sheikh, and flew to Cairo for the pyramids, Sphinx and Egyptian Museum. A great trip overall.

Collage

Egypt:
• Top left: Red Sea beach, Sharm El-Sheikh
• Top right: The author with the Sphinx and the Great Pyramid of Giza
• Bottom left: Burial jars in Egyptian Museum
• Bottom right: Nile cruise.
Images: Joe Holmes © Canadian Museum of Nature

Israeli Sample Locations
Note:

  • Representative diatoms may be in multiple locations.
  • Nahal means “stream” in Hebrew
  • Size scale: 1 µm = 1 micron = 1 millionth of a metre.
Collage

Nahal David, Ein Gedi Nature Reserve near the Dead Sea.
• First: Navicula radiosa (73 µm × 10 µm)
• Top: Cymatopleura elliptica (80 µm × 45 µm)
• Bottom: Biddulphia sp. (70 µm × 56 µm).
Images: Joe Holmes © Canadian Museum of Nature

Collage

Lake Kinneret south shore with Golan Heights.
• Top: Anomoeoneis sphaerophora (47 µm × 15 µm)
• Second: Navicula crytocephala (20 µm × 5 µm)
• Third: Nitzschia obtusa (57 µm × 4 µm)
• Bottom: Mastogloia smithii (30 µm × 10 µm).
Images: Joe Holmes © Canadian Museum of Nature

Collage

Jordan River, southwest of Lake Kinneret.
• Top: Placoneis clementis (17 µm × 7 µm)
• Middle: Staurosirella pinnata (10 µm × 5 µm)
• Bottom: Aulacoseira granulata (25 µm × 12 µm).
Images: Joe Holmes © Canadian Museum of Nature

Collage

Jordan River Yardenit Baptismal Site. Step drainage ditch diatoms.
• First: Navicula capitatoradiata (31 µm × 7 µm)
• Second: Pinnularia kneuckeri (23 µm × 4 µm)
• Third: Amphora coffeaeformis (27 µm × 4 µm).
Images: Joe Holmes © Canadian Museum of Nature

Collage

The author sampling Mezuda Pool North, Ein Afek Nature Reserve near Acre.
• First: Nitzschia acicularis (80 µm × 7 µm)
• Top: Nitzschia compressa (21 µm × 11 µm)
• Middle: Rhoicosphenia curvata (22 µm × 7 µm)
• Bottom: Cocconeis placentula (50 µm × 30 µm).
Images: Joe Holmes © Canadian Museum of Nature

Collage

Banias Nahal Hermon Nature Reserve, Golan.
• First: Navicula tripunctata (45 µm × 8 µm)
• Top: Achnanthes lanceolata (11 µm × 5 µm)
• Bottom: Amphora pediculus (9 µm × 6 µm).
Images: Joe Holmes © Canadian Museum of Nature

Collage

The author beside a fountain on Mount of the Beatitudes, Galilee. Drainage-trough diatoms.
• First: Navicula recens (25 µm × 6 µm)
• Second: Nitzschia amphibia (27 µm × 4 µm)
• Third: Cymbella silesiaca (32 µm × 9 µm).
Images: Joe Holmes © Canadian Museum of Nature

Egyptian Sample Location
I collected some non-sediment “slime” from the Cairo Egyptian Museum pond that yielded a few diatoms.

Collage

Pond and Egyptian Museum diatoms.
• First: Encyonopsis subminuta (14 µm × 4 µm)
• Second: Achnanthidium minutissimum (15 µm × 4 µm)
• Top: Fragilaria construens (5 µm × 3 µm)
• Bottom: Cyclotella kuetzingiana (11 µm × 11 µm).
Images: Joe Holmes © Canadian Museum of Nature

Conclusion
In recent Canadian samples from Ottawa, Ontario, and Vancouver, British Columbia, I saw diatom species that are similar to many above.

Some that I have not seen include

  • Achnanthidium minutissimum
  • Amphora coffeaeformis
  • Cyclotella kuetzingiana
  • Mastogloia smithii
  • Nitzschia acicularis
  • Nitzschia compressa
  • Pinnularia kneucker
  • Biddulphia sp.

It would be worthwhile and interesting to revisit these Middle East countries for more diatom sampling and analysis.

Other articles from Joe Holmes on diatom fieldwork:
“Royal Canadian” Diatoms from the Rideau Hall Pond in Ottawa
Hunting the Urban Diatom in Vancouver, B.C.: Part 1
Hunting the Urban Diatom in Vancouver, B.C.: Part 2
My Irish Diatom Adventure: Part 1
My Irish Diatom Adventure: Part 2

Posted in Fieldwork, Plants and Algae, Research | Tagged , , , , , | Leave a comment

Co-Extinction and the Case of American Chestnut and the Greater Chestnut Weevil (Curculio caryatrypes)

As more and more people inhabit Earth, demanding more and more space and resources from a limited supply of both, the other creatures with which we share the world are going extinct.

People are generally familiar with the plights of the larger and better-known animals, such as mammals and birds, and the reasons that are most commonly at the root of the problem, such as habitat loss and introductions of exotics.

But generally, people are not aware of the large numbers of small, less-conspicuous creatures that are going extinct, if they are not already. In most cases, these smaller creatures are at risk of extinction because of similar threats to their larger distant cousins, but there is one situation where this is not so: co-extinction.

American chestnut (Castanea dentata).

Foliage and immature burrs of American chestnut. Image: Daderot © Public domain

Co-extinction is the loss of a species because the species upon which it depends for survival has vanished.

Co-extinction is poorly understood and there are only a handful of well-documented cases.

Yet, despite this lack of knowledge, the tight associations between the huge numbers of parasites and their hosts, and plant-feeding insect species and the plant species they feed on, may render co-extinction one of the greatest threats to current biodiversity.

Not only does it affect these highly diverse plant-feeding insects and parasites, but the effects of co-extinction are thought likely to cascade down through food webs, resulting in species loss among many unrelated, but successively dependent, organisms.

This is a very serious situation deserving of far more attention than it currently receives.

Two men stand among trees.

Huge American chestnut trees in North Carolina, U.S.A., in 1910. These huge trees have been called the redwoods of the east. Image: Courtesy of the Forest History Society, Durham, NC.

Let’s look at the case of Castanea dentata, the American chestnut. At the turn of the 20th century, Castanea dentata was one of the most important trees in eastern North American forests. Mature trees reached 30 metres in height and over 3 m in diameter; they were colloquially referred to as the redwoods of the east.

However, in 1904 the fungal pathogen Cryphonectria parasitica, or chestnut blight, was introduced to the New York Zoological Park (now the Bronx Zoo) in New York City. The blight quickly spread across the eastern United States and in the course of a few decades, it effectively killed almost all of the chestnut trees in the east.

While new shoots often sprout from the roots remaining after the main trunk has died, blight will continue to infect these new shoots and kill them before they reach any significant size or a mature reproductive state.

A few large trees still survive within the native range, perhaps because of isolation or partial blight resistance, but the reproductive history of these trees is not well known.

Leaves, burrs and nuts arranged on a table.

Some foliage and chestnuts of the American chestnut. Image: Timothy Van Vliet © Timothy Van Vliet (CC BY-SA 3.0)

Like almost all tree species, American chestnut has a number of host-specific insects that feed on it and little, if anything, else. Among these insects are a number of species of moths and at least two species of weevils, the greater and lesser chestnut weevils, Curculio caryatrypes and Curculio sayi, respectively.

According to the International Union for the Conservation of Nature, the reproductive extinction of the American chestnut resulted in the concurrent loss of at least two of these species of moths, Ectodemia castanea and Ectodemia phleophaga, and likely at least five others, some of which were last seen in 1936.

The case of the weevils has not been addressed until now. The lesser chestnut weevil, Curculio sayi, is known to still exist, reproducing in the nuts of other species of Castanea such as introduced Chinese chestnut Castanea mollissima and the native chinkapin Castanea pumila and its southern relatives.

Composite: Two weevils, each with a 2 mm scale bar.

Male (left) and female (right) Curculio caryatrypes. These weevils can be recognized by their large size for the genus Curculio, and by the second segment of the antennal funicle’s (the part beyond the elbow) being obviously longer than the first segment. Females use their much longer snout to excavate small, deep holes in chestnuts into which they lay their eggs. Images: François Génier © Canadian Museum of Nature

However, the most recent study of the taxonomy of the genus Curculio, which brought together thousands of museum specimens of the genus, could find no specimens of Curculio caryatrypes collected any later than 1956. Other efforts at sampling insects living on surviving American chestnut trees have similarly not collected this species.

Spurred by this knowledge (or lack thereof), I recently polled a variety of insect collections throughout the native range of American chestnut to see if they have since added any specimens of this large, distinctive weevil species to their collections.

Sadly, other than two specimens reared in spring 1987 by now-deceased lepidopterist Eugene Munroe and his wife Isobel of Ottawa, Canada (from nuts collected from a large, now-dead American chestnut tree in Prince George County, Maryland, U.S.A.), no other post-1950s specimens have been found.

There are still many reports of weevils in introduced chestnuts and native chinkapins, but where examined, these are all the lesser chestnut weevil, Curculio sayi. Despite some comments in the old agricultural literature to the contrary, it is likely that the greater chestnut weevil was associated only with Castanea dentata. With the demise of that plant, so went the weevil.

Several weevils on a burr.

Male and female Curculio caryatrypes weevils on an American chestnut burr. You can see why the females need such a long rostrum to reach in among the spines to excavate the oviposition hole. Image: © Brooks and Cotton 1929, U.S. Department of Agriculture

It’s not a happy day when we can declare another species as extinct, but today, along with the two species of already red-listed, extinct chestnut moths, I believe that we can now add the greater chestnut weevil (Curculio caryatrypes) to the ever-growing list of extinct organisms.

Perhaps we should now turn our attention to the co-extinction threat being imposed on ash trees and their insect associates by the introduced emerald ash borer (Agrilus planipennis) before that fauna is lost as well.

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Cabinets, Cabinets Everywhere: The Sequel

By Kathlyn Stewart and Michelle Coyne

The story continues of the transfer of some of the National Collections of the Geological Survey of Canada from their home on Booth Street in Ottawa to the research and collection campus of the Canadian Museum of Nature!

An open drawer holding trays of specimens.

Some of the fossil plant type specimens now housed at the museum’s facility. Image: Kathy Stewart © Canadian Museum of Nature

In the previous posting, the first 225 Lane cabinets had just been transported up from the United States to the museum’s Natural Heritage Campus, our research and collections facility in Gatineau, Quebec.

These cabinets will house some of the survey’s huge fossil invertebrate and plant collections. We allocated a space and renamed it the GSC Warehouse. Since that initial shipment, 225 more cabinets have been trucked up, making a total of 450 new cabinets now at our facility.

A plaque on a wall that says, "Comission géologique du Canada / Geological Survey of Canada / A1163".

New name plate for Warehouse 2 at our research and collections facility, which will house the Geological Survey of Canada’s National Plant Type Fossil Collection. Image: Michelle Coyne © Geological Survey of Canada

But these cabinets could not be moved into the warehouse until upgrades there were completed—so, where to put them all? The photo below tells the story: cabinets lining our collection hallways into infinity!

A very long corridor with a double stack of single-door cabinets along one side.

Hundreds of cabinets stored along the main corridors in the museum’s research and collection facility in Gatineau, Quebec. Image: Kathy Stewart © Canadian Museum of Nature

Upgrades to the GSC Warehouse—under the able supervision of the museum’s Martin Leclerc and Pascale Sénéchal—included compactor shelving, security, environmental controls and a fresh coat of paint to ensure the best conservation conditions.

A large room with tracks in the floor and metal frames for moving platforms on the tracks.

Compactor shelving to hold the collections being installed in the GSC Warehouse. Image: Michelle Coyne © Geological Survey of Canada

Meanwhile during the upgrades, the first of the GSC’s National Collections arrived from Booth Street. Two smaller but highly valued GSC collections, the National Meteorite and Tektite Collection, and the National Plant Type Fossil Collection, plus a Quaternary shell collection, were packed and trucked to our facility in late 2015 and early 2016.

Their moves were, in part, a pilot project to test packing methods, conservation needs and moving methods in preparation for future moves.

Meteorites! The Geological Survey’s collection of rock or iron fragments from outer space has attracted much public and scientific attention throughout its history. This collection had an auspicious beginning in 1855 when Sir W.E. Logan acquired the 167.8 kg Madoc Meteorite, the first recognized meteorite in Canada.

A meteorite specimen on a rock pedestal.

The main mass of the Madoc Meteorite, acquired by W.E. Logan. Image: Michelle Coyne © Geological Survey of Canada

Very soon after its discovery, the Madoc Meteorite became internationally known, going on display at the 1855 Universal Exposition in Paris, France.

The meteorite will remain in Logan Hall at the survey’s offices on Booth Street during the celebrations of their 175th anniversary in 2017. It will then move to our facility in Gatineau.

Since its early days, the Geological Survey’s meteorite collection has grown enormously. It now includes more than 3000 samples from 1035 distinct meteorites found in 87 countries.

The collection includes 52 Canadian meteorites, with recent acquisitions from Buzzard Coulee, Saskatchewan, and Tagish Lake near Atlin, British Columbia, by former curator R. Herd, Ph.D.

Tektites—debris caused by meteorite impact—are also in the collection.

A man inserts a drawer into a cabinet.

Carleton University student and survey volunteer Ian Beitz places a tray of meteorite samples in new cabinets. Image: Michelle Coyne © Geological Survey of Canada

The National Plant Type Fossil Collection also made the trip from Booth Street to Gatineau. These specimens were unpacked by staff and volunteers from the Geological Survey and stored in 22 cabinets in our Palaeobiology Collection until they can be moved to the GSC Warehouse. As with all the museum’s collections, they are accessible to scientists and the public.

The National Plant Type Fossil Collection represents fossil species that have been named, illustrated and published in the scientific literature. Walter A. Bell (1889–1969), was with the Geological Survey of Canada from his student days in 1920 to his retirement in 1954 as palaeobotanist and eventually director. In 1962, he published the first comprehensive catalogue of types and figured specimens of fossil mega- and micro-plants in the survey’s collections.

Two women pose with a row of single-door cabinets.

Michelle Coyne, a curator with the Geological Survey, and Alexandria Gaucher-Loksts, a survey volunteer, with the newly arrived National Plant Type Fossil Collection. Image: Kathy Stewart © Canadian Museum of Nature

The survey’s National Plant Type Fossil Collection will be a welcome addition to the museum’s fossil collection, in that many plant specimens were recovered from several of the same sites as vertebrate fossils in the museum’s collection. The plant fossils will provide information about the environment of the vertebrates.

Now, over a year since the last article, much has been accomplished, but much still needs to be done. The online databases and reference database for the Geological Survey’s collections need to be updated—an ongoing process. And much preparation is still needed for the “BIG” move to the museum’s campus of the rest of the survey’s mineral and fossil invertebrate collections. We expect to be filling those 450 cabinets later this year.

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