Archive for the Education Category

CAN YOU SAY OSMETERIUM?

Posted in Butterflies, Defense, Education with tags , , , , , , , on September 16, 2010 by Dr. Art Evans

By Arthur V. Evans

This summer a cadre of dedicated parents and volunteers joined forces at a nearby elementary school to create an outdoor classroom. The Holton Learning Project Garden includes a vegetable and butterfly garden that will introduce Holton Elementary School students, their families, and the residents of Belleview and beyond to the pleasures and benefits of urban gardening.

Compared to the dreary, sterile plantings of exotic trees, shrubs, and groundcovers found throughout much of the neighborhood, the vegetable and nascent butterfly garden has rapidly become a local hot spot for insects and spiders. As such, it provides an excellent site for macro photgraphy. Since August, I have endeavored to photograph as many of its multi-legged denizens as possible as part of an ongoing effort to document the arthropod diversity of my neighborhood in Richmond, Virginia.

While walking through the garden yesterday afternoon, I noticed several clumps of green spikes rising sadly from the straw-covered beds. I soon confirmed my initial suspicions as to the identity of the culprits that laid these once fat bunches of parsley to waste. At the very base of one of the clumps were two brightly banded larvae of the black swallowtail, Papilio polyxenes, polishing off the last few leaves.

When I knelt down to photograph the ravenous caterpillars, I accidentally brushed up against their food plant. Both caterpillars reacted immediately by assuming defensive postures. Bent over backwards, they spit up green fluid and produced a pair of long tentacles (osmeterium), that resembled bright orange horns. Soon my nostrils were filled with a strong, disagreeable odor that is best described as “spicy vomit.”

The osmeterium consists of two soft, finger-like tubes that are everted from inside the body through a slit in the prothorax just behind the head as a result of  increased blood pressure. This defensive gland is found in the caterpillars of swallowtail butterflies and is coated with highly noxious chemical compounds (2-methylbutyric acid and isobutyric acid) that deter predators, especially ants.

© 2010, A.V. Evans

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ALTERNATIVE SPRING BREAK AT THE VCU RICE CENTER

Posted in Education, Environment, Insects, VCU Rice Center, Virginia with tags , , on March 26, 2010 by Dr. Art Evans

By Arthur V. Evans

© 2010, J. Barton

Last week, I met a group of very dedicated and enthusiastic students from the Virginia Commonwealth University and Virginia Wesleyan College at the VCU Rice Center in Charles City County. They had spent the last several days participating in various activities as part of this year’s Alternative Spring Break. Sponsored by the Chesapeake Bay Foundation, Alternative Spring Break provides students with an opportunity to explore and give to their community by providing a week’s worth of environmental and conservation projects, such as planting trees, tending gardens, tidying  up parks and wildlife refuges, and stream cleanups. At the Rice Center, some of the students would have the opportunity to help me with my insect survey.

© 2010, J. Barton

After an impromptu presentation about my survey and some of the methods used to trap insects, my team of volunteers was ready to get started. They grabbed tools and traps and set out for the first trap site. Working like a well-oiled machine and with minimal direction, they quickly established two sets of Malaise, Lindgren, and pit fall traps in less than two hours.

Malaise trap. © 2010, A.V. Evans

What is a Malaise trap you ask? It’s like a tent with its walls on the inside and is specifically designed to capture flying insects, day or night. Upon hitting the internal nylon panels, most insects will eventually work their way up into a collecting container partly filled with alcohol. Malaise traps are usually used to catch flies, bees, and wasps, but other kinds of insects are captured, too. They are typically placed along roads, trails, streams, or forest edges. Up to 1,000 insects a day may be captured in a good site.

Lindgren funnel trap. © 2010, A.V. Evans

Lindgren funnel traps are designed to attract and capture wood-boring beetles and other insects that alight on tree trunks. They consist of a rain and debris guard with a dozen black plastic funnels suspended directly underneath. Attached to the bottom funnel is a specimen receptacle. Each trap is fitted with chemical lures that simulate the odors given off by dead and dying trees. Insects attempting to land on the trap fall down the funnels and into the receptacle at the bottom. Foresters use Lindgren funnel traps to monitor pest insects in stands of managed timber, especially bark beetles.

Pit fall traps connected by drift fences of metal flashing capture small crawling animals,

Pit fall traps. © 2010, A.V. Evans

especially insects and other arthropods. At the end of each drift fence is a single pit fall trap consisting of two 16-ounce plastic drink cups nested in one another and sunk so that the tops are flush with the soil surface. The inner cup is partly filled with environmentally “friendly” antifreeze (propylene glycol). Each cup is covered with 1/2” mesh and flashing to keep out both vertebrates and rain.

© 2010, A.V. Evans

Thank you so very much to all the students who joined me on that wonderful day. Not only did you help get the job done, you also inspired me with your camaraderie, energy, and sense of purpose.

© 2010, A.V. Evans

INSECTS BRING OUT THE INNER CHILD

Posted in Beetles, Education, Grasshoppers & crickets, Insects, Musings, Virginia with tags , on March 18, 2010 by Dr. Art Evans

By Arthur V. Evans

Two wars, recession, earthquakes, and the seemingly endless wrangling of politicians—the news has not been very good lately. These combined with the usual everyday stuff makes it all too easy to get bogged down wondering where the world is headed. But occasionally, I am afforded a welcome change of perspective—that of seeing the world once again through the eyes of a child.

The author at the tender age of 14, or thereabouts, enjoying a summer day on a family camping trip somewhere in California's Sierra Nevada.

I was given this fresh viewpoint awhile back at the grand opening at the new Children’s Garden at the Lewis Ginter Botanical Garden in Richmond, Virginia. The garden is a microcosm of landscapes, plant adaptations, and human-plant interactions. A boardwalk accessible to all winds through various mini environments on its way to the Leafy Overlook and Tree House, introducing visitors to coniferous forests, deciduous woodlands, grasslands, and a butterfly meadow.

Also included is an International Village with Lilliputian playhouses depicting different cultures to demonstrate how people around the world use plants for food, materials, and medicine. As the garden matures, it will continue to be a haven for young naturalists and their families to explore plant diversity with its creeping vines, prickly plants, and inviting blooms, both sweet-smelling and otherwise.

It is also a great place for bug watching. That’s where I came in. I was invited to participate in the grand opening of the Children’s Garden as entomologist Dr. Art Evans, “the bug guy.” My task was to engage garden visitors in a series of bug talks and walks. My display was simple, consisting of a collection of local insects and a variety of popular identification guides for the region, as well as copies of my own magazine and newspaper writings on insects and spiders.

Families flocked around the display, amazed at the local insect diversity. Soon I was peppered with all kinds of questions. “Are they real?” “What is this?” “Does it bite?” “What does it do?” “What do they eat?” “Are they really found around here?”

Within just minutes, my world-weariness melted away. I was once again caught up in the excitement of my audience’s infectious enthusiasm for insects. After meeting with dozens of parents and their children, it dawned on me that there are two types people in this world: those that love insects and those that don’t yet know they love insects.

After answering some questions, I briefly introduced myself to the audience, and talked about some of the things that entomologists do in the world. Then we covered some bug basics, like their number of legs (6), body regions (3), and metamorphosis. Also discussed was how insects differ from other kinds of common garden animals such as spiders (8 legs, 2 body regions), worms (no segmented appendages), and slugs (no external skeleton or appendages).

The best part of the day was the bug walk. It was like going on safari. As we searched for tiny game, our goal was not to collect or kill, but to observe and marvel. The weather was overcast and decidedly cooler from the previous day when I had done my reconnoitering for bug hot spots at the garden. Still, there was plenty of insect hubbub about the flowering plants.

Bumblebees, soldier beetles, thread-wasted wasps, and various kinds of butterflies, skippers and moths clambered over the spikes of small yellow flowers as if they knew that fall had arrived and that warm and sunny days were now numbered. Both adults and youngsters peered into the blooms to admire the diversity and activity of this energetic, winged, and multi-legged assemblage. It was a great demonstration of how both plants and insects depend on one another for their very existence.

Nearby, black swallowtail caterpillars nibbled away on a lone fennel plant beneath the dining room window of the Bloemendaal house. We were all being treated to the fact that eating is job one for growing caterpillars of all stripes. Soon, they would all disappear as quickly as they appeared and transform twice more into entirely different creatures with no resemblance whatsoever to their current state.

The shrubs and low hedges were filled with the songs of amorous male crickets and meadow katydids, all scraping their wings together to produce characteristic chirps, clicks, and rasps to attract a mate.  In just a matter of yards we found more species of insects and spiders than could be found of mammals, birds, or reptiles in the entire garden!

This fabulous hands-on experience reminded me once again of why I got into this field in the first place. Sure, insects, spiders and their relatives are everywhere and are endlessly fascinating in their ways, fueling lifetimes of scientific research and popular writing projects. But I have come to understand that my attraction to all things insect is really about my desire to learn as much as possible of the world around me. I truly believe that the desire to learn is a very basic human need; the day we stop learning is the day we start dying.

To see the natural world through the eyes of children, or adults who have not lost their childlike sense of wonder and awe, is truly a gift. For me, it is a clear reminder of my own wonder and excitement that sparked my lifelong interest in insects nearly 50 years ago. I am confident in my knowledge that there are still plenty of insects and spiders out there to see, learn, and do for at least another 50 years.

The author, down and dirty on his knees at Virginia Beach in 2007, searching for false soldier beetles (Oedemeridae) under driftwood.

One of the great things about being a biologist is that we always get to keep a part of our childhood with us while we conduct fieldwork. It is part and parcel of our various job descriptions to wonder how things work as we get down and dirty on our hands and knees to rake through the soil, muck about in the mud, or slosh around in creeks and ponds. Now I ask you, what could be better than that?

© 2010, A.V. Evans

NATURAL HISTORY COLLECTIONS INFORM PAST, PRESENT, FUTURE

Posted in Education, Environment, Musings with tags on May 26, 2009 by Dr. Art Evans

I recently attended a behind-the-scenes tour of the National Museum of Natural History, part of the Smithsonian Institution’s core network of museums. Although I have worked with museum collections for years, I still had that sense that I was in a scene from Citizen Kane or Indiana Jones as I wandered the labyrinth of hallways and dimly lit passages lined floor-to-ceiling with stacks of cabinets and shelves chock full of specimens from around the world.

Yet, it is sobering to note that over the years natural history collections are on hard times as funding and public interests have waxed and waned. Many universities and smaller museums have divested themselves of their collections of pressed, impaled, pickled, stuffed, and skinned specimens of plants and animals. Administrators, policy makers, and the scientists among them are hard pressed to justify the “care and feeding” of collections, preferring instead to direct ever-shrinking resources into other projects that are more likely to attract supplemental funding. However, as support for collecting and collections dwindles, the need for the information they provide continues to increase.

Biodiversity research has long been the primary motivation behind the use of natural history collections. However, the traditional uses of these collections for the purposes of identification, the study of relationships, and evolutionary biology through the examination and comparison of specimens are only part of the story. These very same specimens are now useful tools for tracking changes in populations and habitats over time.

Like “biological filter paper,” natural history specimens can reveal past and present environmental conditions. Chemical analyses of feathers, hair, bone, muscles, blood, stomach contents, and vegetative tissues are now used to trace migratory movements, uncover feeding behaviors, reveal changes in habitats over time, and determine the epidemiology of diseases that affect animals and crops.

For example, analysis of old egg specimens demonstrated the devastating effect DDT had on bird reproduction and ultimately resulted in legislation that banned its use in this country. Similar studies were conducted to trace the increase of harmful mutations after nuclear accidents (remember Chernobyl?), the origin and movement of crop diseases (think Irish potato famine), and the rise of mercury levels in marine animals.

I have always thought of natural history collections like libraries, only the references contained therein are in the form of specimens. Like books, carefully prepared collections provide unique information that links identity, geography, and history. This is the very information that conservationists rely on to inform their decisions regarding the rarity of species and the potential impacts of climate change on those species.

Like a library, the relevance and vitality of natural history collections is maintained through new acquisitions in the form of specimens gathered during ongoing field surveys. Data gleaned from both rare and common species will better inform scientists and policy makers to address the inevitable challenges wrought by shifting populations and habitats. But will we as a society have the foresight and will to support such endeavors?

©2009, A.V. Evans

OUR SEAS OF PLASTIC

Posted in Aquatic, Education, Environment, Musings on March 30, 2009 by Dr. Art Evans

I want to bring to your attention the efforts of a former colleague of mine at the Natural History Museum of Los Angeles County, Dr. Marcus Eriksen. Marcus is a man of many talents: scientist, educator, author, conservationist, and adventurer. As the Director of Research and Education at the Algalita Marine Research Foundation , he is actively involved in the protection of marine watersheds through research, education, and restoration. Marcus and the AMRF team are at the forefront of studying the massive accumulation of plastic debris in our oceans and the impact of this pollution on marine life and the human food supply. Hundreds of millions of tons of bottles, bottle caps, cigarette lighters, bags, food containers, toys and other plastic items are washed through our watersheds and into our oceans each year.

Phase I of this AMRF study, dubbed “Message in a Bottle,” began with a research voyage into the North Pacific Gyre to investigate plastic pollution that has been dubbed the “Great Pacific Garbage Patch.” In Phase II, Marcus and a colleague sailed 2,600 miles from Los Angeles to Hawaii last summer on a raft made from 15,000 plastic bottles to raise awareness of plastic marine debris fouling our oceans.

Phase III begins on Saturday, 4 April when Marcus and his fiance Anna ride their bicycles 2000 miles from Vancouver, British Columbia to Tijuana, Mexico. Along this route they will distribute samples of plastic debris collected from the North Pacific Gyre to legislators, educators, and organizations to raise awareness of plastic debris in our oceans.

The problem is that plastic is designed to last forever, yet we use it regularly to make products that are thrown away. Although recycling is effective for paper, metal, glass, and other materials, it is not the answer for plastics. And as a petroleum product plastic, like our consumption of gasoline, keeps us dependent upon foreign sources of oil.

The “Message in a Bottle” project has encouraged me to rethink how I use plastic products at home and in the workplace. My first small step into this brave new world is to avoid purchasing or using drinks of any kind in plastic bottles, especially water. Then I am going to try to encourage my favorite take-out eateries to start using more eco-friendly to-go containers. A recent trip to the grocery store was sober reminder of just how pervasive plastic is in our culture, but there are lots of creative people out there who are coming up with practical and interesting ways for reusing and recycling these containers.

If we all do our part, and encourage our colleagues, clients, and visitors to do the same, we can make a difference and help to reduce the amount of plastic debris that finds its way into our oceans!

LEAVE NO CHILD INSIDE

Posted in Education, Environment on February 9, 2009 by Dr. Art Evans

The single most important ingredient that ignited my lifelong passion for insects and all natural history was…freedom.

Supportive parents, teachers, librarians, and scientists all fostered my interest in insects and natural history, but it was the freedom to explore and discover nature at my own pace that really made the difference.

As a youngster, I spent many glorious hours on end wandering along trails, hiking up canyons, mucking about in streams, turning over rocks, examining flowers, and peeling back bark.

These early explorations taught me a great deal about the natural world. They also rewarded me with invaluable self-knowledge that continues to serve me well today—that the outdoors is my own personal refuge.

Sadly, unstructured time for most children has become a thing of the past. Recess time outside has been eliminated from many elementary schools. Overburdened with homework, sports, and other structured activities, children today have little time or inclination to just step out outside and ‘be.’

Freedom to explore, to get dirty, and to be ‘human beings’ instead of ‘human doings’ has all but vanished for children. Studies show that their outdoor time is down by 50% when compared to that of their parents and grandparents.

Cheryl Charles, president of the Children and Nature Network, notes that during the past two or three decades, well-intentioned parents have replaced nature with scheduled activities and events. She notes that technology, such as computers, iPods, television, etc., have their place but are consuming a disproportionate amount of their children’s time.

Parents are justifiably worried about the safety of their children, but the Internet has proven to be more dangerous than the outdoors, which is even more reason to encourage children to spend more time in “green space” than with “screen space.”

As human beings, we need the colors and rhythms that only nature can provide. The sights, smells, and sounds of nature provide us with vivid of memories that last a lifetime.

Years from now it is these shared experiences outdoors—not those in front of a television or computer screen—that will help us and our children to recall family and friends long since gone.

The disjunction between children and nature is not only to their detriment, but also to the detriment of nature itself. After all, we only save what we love and we love only what we know.

According to researchers at Cornell University, children who spend time in the wild fishing and camping before the age of 11 are more likely to grow up to be environmentally-minded and committed as adults.

The very notion of “leave no child behind” must begin with the basic concept of “leave no child inside.” The next time you really want to do something for a child, spend time with them outdoors. Just go out into the yard, or visit a city, state, or national park. It will do you both a world of good.

To learn more about movements to reconnect children with nature visit < http://www.cnaturenet.org/> and the National Wildlife Federation’s “Green Hour” program <www.GreenHour.org>.

©2007, A.V. Evans

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