The adult flies emerge from their galls in late spring.In Manitoba they emerge mid to late May, or even early June.
The adult flies emerge from their galls in late spring.In Manitoba they emerge mid to late May, or even early June.Students write a full lab report describing their results using standard scientific paper formatting.
This laboratory activity is used in labs for an introductory college biology course at a small, liberal arts college.
The lab allows students to address a legitimate scientific question by collecting local organisms in the field, looking at biochemical differences, analyzing numerical data with statistics, and synthesizing their results within the context of previously published papers.
Here's a quick run down of the gall fly biology and some suggestions to help you bring this critter into the class room.
The goldenrod gall fly (Eurosta solidaginis) is a common and widely distributed insect found coast to coast in the central part of North America.
The larva of the Goldenrod Gall Fly () is both common and easy to get.
This insect parasitizes the stems of goldenrod plants causing the plant to produce a large spherical gall on its stem.The larva's chewing and the action of its saliva, which is thought to mimic plant hormones, results in the production of the galls which provide the larva with both food and protection.There they feed and grow, passing through 2 larval stages.Of the many different kinds of goldenrods found in Manitoba, the flies are known to use only two, graceful goldenrod ().The former of these two, graceful goldenrod, is by far the most common host for the gall flies in Manitoba.(They have difficulty righting themselves if they fall on their backs! Adult flies only live about 2 weeks, during which time they mate and the females lay their eggs.They deposit them at the tip of the emerging goldenrod stems, and they are pretty choosy about which goldenrod species they use.Students determine the genotype of each gall fly; students compare the combined class' genotypes for the two groups of gall flies statistically using chi-square analysis.Students read a related scientific paper and discuss it in a subsequent lab session.The Guide's format is designed to be student-friendly, with short summaries of what belongs in each section followed by lengthier FAQ-style information.Students often realize the benefits of using the Lab Report Guide after they receive grades on their drafts of Materials and Methods and Results sections.