Biodiversity Research and Education

In the image above there are at least four species of lichens all clustered closely on the bark of an elm tree close to my lab on the campus green. There’s a lot to love about lichens, especially for naturalists who are intrigued by the nature of diversity. Lichen forms are surprisingly diverse, sharing common core features but an extraordinary array of colors, patterns and habits.

The lichens above include the bright  orange-green sunburst lichen at center (Xanthoria parietina), a white powdery rim lichen in the genus Lecanora at the lower right, a chartreuse and turquoise comma lichen spread across the top of the photo, and a gray-green lacy rosette lichen (Physcia) tucked in above the sunburst.

One of the other features of lichens that makes them an attractive focus of observation and study is that many are available to be photographed and cataloged even on the coldest days of mid-winter when a majority of other species are absent, dormant, or leafless.

Here’s a lichen that is comfortable on stone or concrete substrates as well as tree bark – it is so closely matched in color to the cement it is all too easy to miss it completely until someone points it out.

In many environments, lichens can be found on an amazing array of surfaces – take a closer look and you will find a world of intricacy and detail that escapes our gaze most of the time.

Halictus rubicundus, the orange-legged furrow bee on spearmint flowers outside the public library in Middlebury, Vermont.

I’m struck by the remarkable diversity of bees right in the middle of the extraordinary array of diverse other living things – beetles, flowering plants, fungi. At the same time, I’ve noticed from listening and watching conversations that the broad public sense of ‘bee’ is generally held mostly by the cosmopolitan honeybees and the sense of a hive or colony, or a vague idea of bees, wasps and hornets, again with a sense of colonies and nests and lots of stinging. Bumblebees are part of most peoples’ awareness too – their larger size and relatively slow flower-to-flower foraging behavior makes them relatively  easy to observe. The surprise comes when you decide to really park yourself in the middle of a broad patch of different blooming wildflowers – coneflowers and mountain mint and St. John’s wort and roses, wild carrot and asters, milkweed and chicory – then if you really watch closely you begin to see more of who is working the different blossoms.

Two flavid cuckoo bumblebees, Bombus flavidus, in Glacier National Park, Flathead County, Montana, July 2021.

It doesn’t take long to recognize that in addition to the honeybees and bumblebees, there will be five, six, seven or more different kinds of other bees, and bee-like flowerflies too. These “other” bees, many of which are our native bees (part of the ‘apifauna’) are often smaller than honeybees or bumblebees, sometimes quite tiny. In many cases they fly in and out faster or move more rapidly from one patch of flower to another, and they typically require a little more patience and a sharp eye to get a really good look.

A brilliantly green Halicitid sweat bee in the genus Agapostemon on the grounds of London Grove Friends Meeting, Chester Co., PA, May 31, 2021

In the meadows and gardens I’ve been watching this summer, in both the east and the west, one of the families I’ve been enjoying is the Megachilidae – the leafcutter bees, resin bees and carder bees. It is said that this family may hold up to 20% of all named bee species. These bees are solitary bees that do not work from hives or social groups. At the same time, they are also very effective pollinators for many plants and some have been used intentionally for that purpose. The leafcutter bees, in the genus Megachile, are so named for their very noticeable behavior of cutting circular patches of leaf from the margin of chosen plants to use in the construction of a nest that is sometimes compared to a cigar in shape and proportions. They also collect pollen as a food source to provision brood cells in the leaf-skin nest, so that the eggs they lay will hatch to a ready and nutritious supply of larval sustenance. 

The Broad handed leafcutter bee, Megachile latimanus, on chicory flower, Addison County, Vermont, August 2021

I was surprised to find among bees I observed that there are several species that are not native at all but are introduced, either accidentally or intentionally, and a few of these have become well established, perhaps posing some competitive stress to our native Megachilid species. We often think about introduced or even invasive weeds, and other more obvious pest insects (thinking spotted lanternfly for example), but I had not yet known about these non-native, solitary Megachilid bees that are complicating the ecological relationships among native insect and plant species. 

Anthidium manicatum, the European wool carder bee, guarding territory and chasing other bees away in a native plant pollinator garden, Wynnewood PA. We do have native “wool carder” bees too – this isn’t one of them!

Native Megachilid bees can be supported with nesting sites or nesting boxes (see below), and like many other insects, they benefit from a diverse habitat with different pollen and nectar sources that flower across a long blooming season. Watch for their distinctive shape and abdomen next time you see a patch of flowers being worked by honeybees. 

Among the diverse and colorful mushrooms I photographed last summer,  one that most stood out to me was a bottle green Russula growing in a grass trail immediately next to a hardwood forest. Of course I wanted to know what it was, but in exploring possible identities, I soon learned that the genus is complex and a group of mushrooms known previously as Russula virescens (a European species) probably contained quite a number of distinct and unpublished species waiting to be disentangled. This week, I thought I would return to the locale of my previous green mushroom sighting to see if I might get lucky enough to see it again. It seemed like a long shot, but indeed at almost the very same location on the trail, and (mostly) spared by a recent pass of the lawnmower, were five or six fruiting specimens. Now I can’t be entirely certain this is the same fungus, and it was much more of a gray green than last year’s spinach green, but I think it probably is the same.

Identifying mushrooms definitively is not always simple, owing both to the variety of form within a species and the similarities between species, but the effort is helped by studying the spores. The first and simplest piece of data comes from a spore print, a collection on paper of spores that rain down from an undisturbed mushroom cap left in a quiet place for several hours to deposit a layer of spores that often shows the pattern of gills – the color of the spore print is sometimes a quick telltale identifier, but is always useful information. The spore print of my green Russulas was a distinct buttercream yellow, as you can see below. (It also deposited two white worm-like fly larvae who had been feeding in the cap). I checked to see if the spores fluoresced under UV light – some Russula spores and spore prints fluoresce brightly and after handling them, your hands will light up under a blacklight too! They did not fluoresce unders shortwave or longwave UV.

Finally, studying the spores themselves under a microscope is valuable, and ultimately, a DNA sequence provides one of the most distinguishing pieces of evidence for the identity of the fungus. Here the shape and the surface of the spores themselves can be seen at about 400x magnification:

So what is it? I don’t know! In fact, I have a feeling that perhaps nobody knows! It might be Russula subgraminicolor, a species well documented in Texas. It seems unlikely to be Russula parvovirescens, a species first described in 2006 that does occur in Pennsylvania. But it just as well might be a mushroom without a name, a fungus waiting to be more fully known and mapped. This time, I carefully saved a small piece of gills for drying preservation for DNA possibilities.

Osage orange trees (Maclura pomifera) are impressive in many different ways; they likely arose some 25 to 30 million years ago, a branch from a South American mulberry family lineage that appears also to have given rise to the modern Maclura brasiliensis. The species is a survivor of the last glacial age, pushed into a narrow pocket of the Red River region of Arkansas, a geographic range that might have seen its diminishment and ultimate extinction were it not to be adopted by humans as incredibly useful for a number of purposes. The large aromatic, sticky green fruits were once eaten (and seeds dispersed) by extinct mammoths and ground sloths.

Osage orange fruits and foliage fallen from a 20th century hedgerow

Without these natural dispersers, the trees diminished range would have probably shrunk to nothing. But the wood of the tree was prized for bow wood by the Wazhazhe (Osage) people in the Missouri – Arkansas region. European settlers found the tree to be a valuable hedgerow species as it formed dense thorny thickets of wood that was readily coppiced. The abundant sprouts produced from a cut stump made excellent post wood and a high density firewood. The wood is one of the most decay resistant wood of any deciduous species, and it was also a choice wood for wagon wheels.  In the 1930s, osage orange planting was part of a concerted effort to create shelterbelts during the great drought years in an effort to provide windbreaks and reduce soil erosion. Today, you will often find osage orange trees not singly but in long lines, remnants of field edges and hedgerows that are often long gone.

This osage orange in Queen Anne’s County Maryland shows a beautiful example of the orange color of the wood under the bark, also visible on exposed roots. The nearby trunk of a recently cut osage orange tells a 20th century history and climatology. The tree appears to have been planted (among a great many trees in a long line) on what is today the Ferry Point Trail on Wye Island in about 1930. In years that followed the tree grew through nearly a century of cyclical wet and dry periods, including several intense drought periods. The growth rings below correspond well in places to Maryland climatological data that documents exceptionally dry years in 1965-66, 1976-77, and 2001-02. The banding pattern is made by the difference in xylem vessels laid down as earlywood (spering wood – light) and latewood (summer wood – dark). The chemistry of the darker colored sapwood of osage orange is complex, and contains significant quantities of an analog of resveratrol called tetrahydroxystilbene, a multi-ring organic phenol with notable biological activity that is suspected to be at least partly responsible for the wood’s antifungal rot resistance.

Osage orange trunk with narrow growth rings marked in years corresponding to dry/ drought seasons as indicated in black type

Maryland climate data dating back to 1895 with drought periods indicated by orange spikes above baseline and wet years with blue-green spikes below baseline. Note great drought of 1930 and especially dry periods around 1965 and 2002.

A chance encounter near Emory Pass in southwestern New Mexico in 2017 started a journey of three years to uncover a lost species of day flying moth.

The landscape along Highway 152 near Emory Pass in Sierra County, New Mexico.

It wasn’t really lost to itself – the moth has been flying in the hills of Colorado, Texas, Arizona and New Mexico for centuries. But it had lost its unique identity. In 1882, on one of the earliest entomological expeditions to the frontier regions of New Mexico, one of the first professors of the University of Kansas (F.H. Snow) set up a field camp in the Gallinas River valley near Montezuma NM. Among the many insects Snow collected and brought back for study was a black and white moth that was soon recognized and named as a new species. A British entomologist praised Professor Snow and named the new species Alypiodes flavilinguis, the specific name referencing the bright golden-colored tongue of the strikingly marked moth. By 1901, the name and the species were dropped as Snow’s New Mexico species was believed to be just an extension of a previously named moth described from Mexico, Alypiodes bimaculata. With only adult moths to study, that choice seemed logical and appropriate at the time. In the last two years, a group of dedicated and curious students in our lab pursuing DNA sequencing work uncovered clear indications that Snow’s A. flavilinguis was not at all the same as A. bimaculata, and parallel studies of southwestern caterpillars by Dave Wagner at University of Connecticut offered another important line of confirming evidence. It’s a great story – after 100 years of being overlooked, a new journal article that is forthcoming will restore the species status of a moth first named in 1882. It’s not hard to see why it was overlooked – in the images below, the New Mexican Alypiodes flavilinguis is above while the very similar looking Alypiodes bimaculata is below. Differences between the adults are subtle and at first appearance would seem to fall well within the range of variability often found in a single species.

Alypiodes flavilinguis from Grant Co.,NM

Alypiodes bimaculata from Cochise Co., Arizona

Few things are as satisfying to a naturalist as walking through native habitats and observing, learning in the field about what lives where, what makes up the living fabric of the landscape. In unfamiliar locations, I often photograph interesting plants, insects or fungus then use the photographs later to study and identify the different species.

Here for example (pics just below) in northern New Mexico was a striking member of the Aster family, with gummy yellow disk flowers and almost no ray flowers at all. A scan of potential New Mexico wildflowers led to the possibility of a Grindelia species, and the SEInet map helped to narrow it to Grindelia nuda or Grindelia squarrosa (red dots on the map below represent collected and verified herbarium specimens of Grindelia species).

Further reading showed that some botanists consider these two plants, Grindelia nuda and Grindelia squarrosa to be one species, so I’m comfortable for the purposes of my own thinking to consider it “curlycup gumweed” or Grindelia squarossa.

Numerous references reveal the plant to be an important traditional medicinal species among the Blackfoot, Cheyenne, Cree, Dakota, Paiute and Shoshone healers. What little is known of its chemistry indicates it is complex, containing a wide array of terpenoids, flavonoids and sterols, some of which may be unique to the genus. At least one diterpene has been shown to have potent antifungal activity and other compounds are antibiotic.

Grindelia plants were photographed near the Cañon de Ojo Sabina, below, northwest of Montezuma.

At higher elevations northwest of Santa Fe, I passed a patch of what was clearly goldenrod, but a wand-like, purple-stemmed species I don’t know from eastern fields and meadows. A little work on high altitude Solidago species of the west clearly identified this as Solidago muiltiradiata, the alpine goldenrod or Rocky Mountain goldenrod.

Back home in the East, this ‘goldenrod’ from the Franklin Parker Preserve in the New Jersey Pinelands turned out to be a Euthamia species, not a Solidago at all. Named ‘slender goldentop,’ Euthamia caroliniana was formerly classified as a goldenrod in the genus Solidago but both morphological differences and DNA data supported the creation of a distinct and separate sister genus.

I visited the same stream bank on the Willimantic River that I photographed in October just a couple years ago. Change is the one constant in most landscapes, and I was struck by how different the same place looked. There was the obvious  increase in streamflow after many days of spring rains, making it impossible for me to walk out on rocks beyond the river’s edge as I had in October. And a birch tree had fallen into the stream just below the spot where I had stood, its long, white trunk extending almost to the middle of the river. Just a little further downstream, I could make out what could be the new construction of beavers (they are found on the river) or just a pile-up from a seasonal flood as a dam of stacked branches and logs that undoubtedly was changing the watercourse in important ways. You can see it if you look back into the photo.

Spring slowly arriving at Friends’ Central – the seasonal moths return

Male Paleacrita vernata moth, resting with wings folded in the early morning hours on brick mortar under a light on the rear wall of the FCC, 28 February 2018

The end of winter and the coming of spring in Pennsylvania is marked by many seasonal indicators – flowers on the willow branches as catkins open up along the Phragmites marsh, loud calls from perching red-winged blackbirds, and of course the appearance of the males of the spring cankerworm moth, Paleacrita vernata. These Geometrid moths often end up on the brick walls under the lights of our science building. It’s easy to know the moths on the wall are males since the corresponding females of the species are both wingless and flightless. After climbing up a tree trunk from the soil, they mate with a male and lay eggs on a small branch. Soon the caterpillars will be feeding on newly emerged foliage.

Spread male specimen of Paleacrita vernata. Females are wingless and flightless.

Feeding larva of Paleacrita vernata, found in oak catkins from trees near the baseball field, May 2007.

Willimantic River, northeastern Connecticut, mid-October

As students and scientists, we can always be on the forefront of knowing, discovering, seeing and understanding what is happening in the world and then recognizing what we can do to promote diversity, protect fragile ecosystems, preserve critical habitat, restore degraded lands, clean up streams and rivers, reduce hazardous emissions to air and water, minimize waste. Our actions matter. Nothing is small. Anything and everything we do can and does make a difference. Planting a tree, reducing our own consumption, protecting a piece of habitat. It all matters. (See this video – the power and responsibility of the individual…) We can also take our lead from other scientists, advocates, and researchers who are working hard to shine a light on complex processes. There are dozens or even hundreds of non-profit organizations dedicated to making a meaningful difference on our planet. These groups are local, national, international and global.  We can partner with these organizations or use them as inspiration to start our own initiatives. There’s never been a more important moment to use our energy, lift our voices, and participate fully in a collective effort on behalf of all the natural resources that support life.

Organizations to explore, support and learn from:

The Nature Conservancy – nature.org

Conservation International – conservation.org

The National Audubon Society – audubon.org

Wetlands International – wetlands.org

International Union for the Conservation of Nature – iucn.org

Global Biodiversity Information Facility – gbif.org

How is climate change linked to biodiversity and conservation biology – read more here: http://blog.nature.org/science/category/climate-change/

The evolution of diversity is a process that requires enormous periods of time, lengths of time that are difficult for our human minds to feel or understand. Three million years, for example, is a fairly brief interval in the evolutionary history of invertebrates, but it would represent many hundreds of thousands of human generations. In fact, our human ancestors of three million years ago would be hardly recognizable to us as sisters and brothers (at least they don’t look much like my sister or brother – you may wish to consult photos of your own relatives for verification of this). Our ancient Australopithecine cousins, posing by some rugged meal or a few rocks in natural history museum displays or painted in color plates in a popular magazine article, hardly look like our neighbors or our great-grandparents. Yet we all seem fascinated by some recognition of our earlier selves there. We have come a long way in physical and cultural changes since that era, but the time passed is still exceedingly small in the grander scheme of life on earth. Real diversity requires substantial time to accumulate genetic differences, to segregate reproducing populations, to allow favored forms in new or different conditions to increase their numbers in the gene pool. The creativity within that process is nothing short of breathtaking, and it was largely this sense of unfathomable wonder that attracted me to natural history in the first place. How is it really possible, I wondered, that these magnificent lilies, the incredible sacred ibis, the delightful morel fungus could emerge as life entities on this remarkable planet. Of course the more I learned and understood about the physical mechanisms of the evolution, the more profound and wonderful the creative mystery became in my mind. I don’t mean mystery in the sense that I could not comprehend the processes that had taken place to bring us here. The wonder was that they do take place, and in a way that is so exquisitely intricate as to be a kind of molecular symphony, played out in energy and time. And that is still how I see our precious biodiversity today, a symphonic accomplishment of complexity working to bring pattern out of chaos at a level that is almost incomprehensibly rich at every level. Seen in this light, even a single green moth, flying erratically on a warm summer breeze through an oak forest some moonless summer night, even this moth has everything to teach us about spirit and self. Even there in the humble moth or the oak leaf, we can discover our own true nature.