The Scientific Method: A Reality Check

If you have ever heard someone say “I have a theory about that” they don’t. They’re most likely confusing the word “theory” with “completely unsupported, untested hypothesis”. All kidding aside, the words “theory” and “hypothesis” mean something very specific to a scientist, and the former is actually a much stronger statement than the latter. Since most people are not scientists but sometimes need to judge the value of someone’s statements, it can be useful to have at least a rudimentary understanding of how the scientific process works.

The journey to creating a theory is a long and arduous one and, in fact, one that most scientists will only ever contribute peripherally to. But every journey starts with a first step so that is where we will begin. In addition to the scientific jargon, I have taken the liberty of translating it into everyday vernacu… umm, language (it’s hard to stop using big words when you’ve spent 22 years in school).

Step 8

Write a paper for a peer reviewed journal.
Translation: Spend several months preparing a paper and ensuring that the formatting meets the requirements of the most prestigious journal in your field. Submit. Receive rejection letter. Reformat your paper for a less prestigious journal and submit. Receive scathing peer reviews of your paper. Swear. Reluctantly make suggested changes to the paper while grumbling about it to anyone that will listen. Even more reluctantly conclude that the reviewers’ changes do indeed greatly improve your paper. Submit final version. Send a reprint to your mother.

Although I was intentionally being silly, the fact of the matter is that a research project never goes off without a hitch.   Science is certainly one thing: a learning experience.

Last week I went blitzing-BIOblitzing that is. What, you may ask is a BioBlitz? BioBlitz’s are biological surveys that are periodically held by conservation organizations or universities to identify the species of plants, animals and fungi that inhabit a particular tract of land. In Manitoba, the Nature Conservancy of Canada (NCC) periodically holds BioBlitz’s to identify the species on new properties that it acquires. The BioBlitz that I just participated in was of NCC’s recently acquired Fort Ellice property near the Saskatchewan border, just south of St. Lazare.

Having never been on a BioBlitz before, I wasn’t entirely sure what to expect. It turned out to be two days of hiking along the lovely Assiniboine River Valley, visiting with biologists I hadn’t seen for quite a while and seeing some beautiful rare plants, insects, and birds. It also meant getting covered in ticks and a boot-full of muddy swamp water but those are the normal hazards of field work.

Doing a survey with a large group of botanists made the event much more effective because if one of us didn’t know what a plant species was, someone else did. It was as if we had formed one big, really smart superbotanist! In addition to the plant people, there were also birders, a range manager, ecologists, bug catchers, a mammal expert, a couple of fungus guys, and even an archaeologist. We recorded all of the species we saw, and any plant, lichen, or fungus we couldn’t identify was collected to examine in the lab.

Highlights of the trip included spectacular sand dunes, a babbling brook, a recently hatched Sphinx Moth, mating Tiger Moths, and one of the largest morels I’ve ever seen. Now comes the sad part: waiting for the next BioBlitz so I can do it all over again!

Many people love to garden. But the way you garden can have a negative impact on the environment or a positive one. “Green” gardens are cheaper to maintain as they do not require high inputs of water, fertilizers, pesticides, or fossil fuels, and provide habitat for the many wild plants and animals that share our planet. Here are some tips to increase how “green” your garden is.

• Consider replacing some of the lawn you don’t use with trees, shrubs and/or flowers as they provide better habitat for beneficial insect and birds.
• Correct placement of trees and shrubs can also improve the energy efficiency of your home. Evergreens planted on the north side of your house block cold north winds while deciduous trees on the south side let the sun warm your home in winter but block it in the summer when it’s hot.
• Don’t even try to grow grass in dense shade. Cover with mulch or plant hardy, attractive, native ground covers like Western Canada Violet or Canada Anemone.

• Grow at least some native plants in your yard. Native plants are adapted for the climatic conditions that we get in Manitoba, requiring no fertilizers or supplemental watering when grown in the proper spot. Native plants provide food for many birds and beneficial insects like bees and hoverflies.
• If you like to grow exotic plants, include some that provide food for birds and/or insects. Many horticultural species like hydrangeas, peonies, begonias and fancy “double flowers” are not very attractive to our native pollinators. Exotic plants that do provide food for pollinators include: columbine, delphinium, globe thistle, mint, oregano, Goat’s-beard, and many more.

• Remember to put your yard waste  out for collection along with your recyclables and garbage if you live in Winnipeg.
• For more information on green gardening pick up the “Naturescape Manitoba” book published by the Manitoba Naturalists Society (Nature Manitoba).

Last summer I went to Spruce Woods Provincial Park to determine which insects pollinate the rare Hairy Prairie-clover plant, a species that only occurs in sand dunes. Oddly enough, even though Hairy Prairie-clover is rare, it was being visited more frequently than some of the common plants I have observed. But there was a dark side to all that activity: it was drenched in blood-the blood of innocents! Instead of the cute, fuzzy little bumblebees I had grown accustomed to watching, I encountered big, black and yellow or red wasps and large, colourful wasp-like flies! What were those crazy creatures? When I got my insect identifications back recently, I was shocked to discover that 40% of the species and 67% of the insect visits to Hairy Prairie-clover were by solitary hunting wasps and parasitic flies that prey on other insects.

The Sand Wasp (Bembix pruinosa) was the most frequent flower visitor to Hairy Prairie-clover. Although adult Sand Wasps consume pollen and nectar, the females also capture and paralyze small flies (e.g. Soldier and Horse Flies) to feed to their babies. The Sand Wasp larvae and paralyzed prey are well hidden in underground burrows. A related species of wasp called a “bee-wolf” (Philanthus sp.) was observed capturing and flying away with tiny Andrenid Bees (Perdita perpallida) that were busy pollinating Hairy Prairie-clover.

The Common Thread-waisted Wasp (Ammophila procera) is also a solitary hunting wasp but captures the caterpillars of Noctuid moths called Prominents (Notodontidae) instead of flies. A similar looking species, the Great Black Wasp (Sphex pensylvanicus), captures and paralyzes grasshopper or katydid larvae, and lays an egg on it to act as baby food. The Grasshopper Bee Fly (Systoechus vulgaris) also parasitizes grasshopper eggs. The female Grasshopper Bee Fly shoots her eggs in an area of loose soil suspected to contain grasshopper eggs. The hatched larvae crawl around in the soil until they find a suitable grasshopper host and then they suck it dry!

Similarly, the larvae of large Scoliid Wasps (Trielis octomaculata), are ectoparasites on Scarab Beetle (Scarabaeidae) larvae. The large females hunt down the beetle larvae in the soil, paralyze them and lay an egg on them. Some Scoliid wasps have even been used for the biocontrol of white grubs on sugar cane crops.

And those wasp-like flies? They were Conopid or Thick-headed Flies. The female flies lay their eggs inside bees or wasps. The hatched larva then slowly eats its host until it dies, eventually bursting from the exoskeleton after pupation.

Ironically, even the parasitic wasps are themselves parasitized. The females of the Bee Fly Exoprosopa shoot their eggs into the burrows of solitary hunting wasps, and the hatched larvae develop as external parasitoids. What a fascinating series of biological interactions surrounding just a single plant. Clearly it’s an insect-eat-insect-eat-insect-eat-plant world out there!