Discussion: Does a Spanish moss on a lower branch experience conditions different from that in the canopy?
Why do some insects shelter under bark plates? Is an oak trunk fissure different from the surrounding “plateaus”?
What insects live in the foliage or needles; the trunk; the small branches; the cones (if pine used)? etc. etc.
4. The Forest and the Trees
Question: How does the natural environment change if mapped at different scales?
Framework: I.2.b (l.2.a., many others).
Note: Hey, this reinforces “mapping” and geography skills!
Background Information: A brief discussion of “scale,” using maps available in the classroom.
How To Do It: Then, outside, students choose at least 2 areas of the schoolyard to map (could be a tree-lined border, or a shrubby lot, or a mowed lawn, or the concrete play-yard, or a sidewalk).
Different pairs of students map at different scales, labeling different “patches” at the scale of their map, and compare results. For example, in mowed lawn one pair maps at scale of pilot in airplane flying overhead; one pair maps at scale of entire schoolyard, including all patches in schoolyard; one maps at scale of lawn (borders of map = border of lawn), indicating bare patches, major ant hills, paths, large patches of different kinds of plants (e.g., clover vs. grass); other pair maps at scale of 5 x 5 m quadrat, showing location of ant (hills/mounds, clonal plants, small-scale patches, etc.; one maps at scale of about 1 x 1 meter, showing individual plants (but not grass blades), small ant holes, and all other heterogeneity at that scale; one maps at scale of about l0 cm x 10 cm or less, showing individual grass blades & very fine scale; one maps at scale of ca. 1 x 1 cm, showing all detail in that tiny quadrat; one maps at scale of individual grass blade, showing heterogeneity (e.g., base and tip of blade have very different characteristics & microclimates); etc.
Discussion: Compare results at end, and imagine yourself organism of various sizes, increasingly large or increasingly small.
If the wooded edge of a schoolyard has been chosen, briefly the scales might be: at a distance, just the elongated edge; closer up, distinguish tree canopy from mid-tree from bases; closer up, distinguish individual trunks and map by species; closer up, individual tree in all its complexity; closer up, single branch with all its complexity; closer up, single twig with all its complexity; closer up, single leaf with all its complexity.
5. Microhabitats and Microclimates
Question: How many really different microhabitats can you find, and how do their physical features differ from those of the “general” climate?
Framework: I.2.a (and others).
Background Information: Describe what a “microhabitat” is to students (if they have had previous activities, this should be easy).
How To Do It: Then have a contest to see which team can accumulate the greatest number and the greatest diversity of microclimates. They must list these and note, if possible, what’s special about each. Examples: north and south sides of tree trunks (north is moist and shady, south can be dry and sunny); top & bottom of leaf (top sunny, exposed, warm; bottom sheltered and shady); top & bottom of small plant (“canopy” and understory” of plant); concrete vs. grass vs. unmowed herbage vs. forest edge; under a tree vs. open; in leaf litter vs. open field; under rocks or boards; sand vs. grass; sides of building; under waterspouts; etc. etc.
Discussion: Discuss which are less stressful than general overall climate, which are more.
Discuss which ones are shady and cool, which warm and sunny (might different organisms thus have different preferences?), which are dry, which wet, which are “buffered” from diurnal/seasonal change, which exacerbate such change, etc., and what all of this means to organisms.
6. How Do You Like It?
Question: Are certain organisms associated with certain microhabitats, due to special physical features of those microhabitats?
Note: This should be done immediately following the above.
Framework: I.2.a (I.2.c., I.2.d., I.3c, III.12)
How To Do It: Have different students choose different organisms known to exist on the school grounds, and seek them, describing the physical conditions under which they’re found.
Discussion: End result will be to speculate on why some organisms appear to be restricted to only a few of the schoolyard’s sites. For example, where do you find moss? beetle grubs? fire ants? cone ants? grasses? ferns? ant lions? clover? lichens? fungus?
7. Big Teeth, Little Teeth
Question: Do students and ants perceive a sandwich differently?
Note: A quick and dirty lunchtime activity.
Season: F, S (W during warm spells).
Needed: This requires that students eat lunch outside, in an area where some ants are seen to be scurrying around.
Background Information: The concept of “fine-grained” vs. “coarse-grained” might come in here. To a student, the sandwich is “fine-grained,” i.e., the different components are really quite small relative to mouth size. To an ant, the sandwich is extremely “coarse-grained,” and ants can easily select from among grain types (peanut butter vs. jelly-soaked bread vs. plain bread, for example). Now, just because the environment is coarse-grained for ants doesn’t mean they have to forage selectively—an ant could sample from the sandwich in the exact proportions in which the components occur—but it’s sure easy to forage selectively. Note also that the students don’t have to treat the sandwich as if it’s fine-grained; with some effort, they can selectively forage on one or the other grain type, but this is relatively difficult (I bet the student who eats her/his sandwich whole gets done faster than the fastidious sandwich-dissector). I’ve expressed this all in very complex terminology, but I think it can be translated very easily (my 5-year-old daughter understood the concept). For discussion, think about how a cow and a grasshopper would perceive the schoolyard lawn. A cow would perceive the lawn as a “fine-grained” environment, taking in mouthfuls that might include several kinds of plants at once. The grasshopper would view the same lawn as a coarse mosaic of different kinds of food, and might choose to forage on one particular kind of grain (say, one species of plant). Again, note that the cow could, with some patience, select or avoid individual plants, but that this process takes concentration. Note also that the grasshopper could move from grain to grain randomly, eating each in turn—but at least the small body size of the grasshopper would enable it to choose only a single kind of food plant if such selectivity were of benefit.
How To Do It: First, ask students to think about how they perceive a sandwich: it’s a combination of different foods, just the right size to stuff into the mouth so that all flavors and textures blend together (also easier to eat that way). Hopefully you won’t have any students who dissect the sandwich and eat the components separately, or the whole idea is blown (but see below). Ask each student to donate a small cross-section of sandwich to the ants. Watch the ants arrive at the sandwich, sample it, and then select a portion to carry back to the nest.
Discussion: Do the ants forage selectively from among the sandwich components? Do they treat the sandwich as students do, or is the sandwich “coarse-grained” to them? Can they select from among parts of the sandwich and ignore the less favorite parts?
8. Tree Choice by Mosses
Question: Why do mosses grow on some trees but not on others?
Framework: I.2.a. (I.3.c., many others).
Background Information: Start with brief discussion on mosses, life cycles & requirements (very brief).
How To Do It: Hunt for mosses on trees.
Discussion: Which trees have the most mosses? Which have none? Why? Allow students to speculate and build on each other’s arguments. Are there physical diffences? habitat (and thus physical differences? “flakiness” differences (e.g., pines)?
Hey, could there maybe chemical differences? Do mosses live on strong, resin-scented barks? Do mosses do anything bad to tree, so that some trees have “moss-away” devices, or are “moss-guard” traits simple inadvertent outcomes of other things trees are doing?
9. Chicken Soup, Boots
Question: Do “palm boots” in different microhabitats hold different organisms, and why?
Framework: I.2.a (III.12.b, many others depending on which animals found).
Needed: This requires cabbage palms or other palm with the leaf bases still stuck on the trunk, present on the property.
How To Do It: First, scavenge a palm boot and discover all the things that live there. Then, start examining palm boots in grossly different physical environments, make a careful list of what’s in each, and compare lists.
Discussion: Are there consistent differences between the animal (and plant) lists? Why might this be so? Can different animals (and plants) tolerate heat/light/drought to different degrees? What are all those animals and plants doing in there, anyway? Eating the dead plant matter? Eating one another? Resting? Hiding? Sleeping during the day, getting ready for a heavy night? Just passing through? Using the boot as a “central place” from which to make forays (e.g., ants)?
Note that we’ve compared several palm boots in each of two grossly different kinds of physical situations. Do all boots in one kind of microhabitat have identical species lists? of course not. So, if we were to choose just one palm boot from each physical condition, and we found these had different species lists, could we say that the difference between them was because they were in different microhabitats? Or not? Haven’t you just said that there are chance differences even among different palm boots in the same habitat? Now, this might be bit much, but if presented properly it might begin to get across the very basic idea of “pseudoreplication” and “repeated sampling” and “natural variation.”
10. Paper (Towel) Chase............
Question: How do heat, light, and moisture vary among microhabitats?
Season: F, S (W on bright warm days).
Special Equipment Needed: Outdoor or lab thermometers. I assume that paper towels and water are not special equipment.
Note: Do at your own risk. Haven’t tried it.
How To Do It: Have students wander around checking out different microhabitats with moistened paper towel and thermometer. Carry damp towels in a plastic bag. In each microhabitat, take the temperature (let thermometer equilibrate if possible) and see if the paper towel dries out. I’d suggest that you give thermometer and towel 2 minutes at most; for the towel, at least, just record whether it’s damp, slightly moist, or entirely dry after a 2 minute interval. Also note the “brightness” of a microhabitat on a relative scale (squinty bright, sunny, shady, dark shady). Speculate on the presence or absence of “nutrients” for plants in different sites.
Try sampling, for example, the surface of exposed sand versus 20 cm above same. Compare the surface of exposed sand to versus grassy lawn. Try a spot next to the part of the air conditioner that sits outside a building (Feel all that hot air? What does it do to paper towels and thermometers? To plants?) Check out a spot right next to a building versus one meter away from it. Compare a spot near the ground level; in the shade vs. full sun; under a tree canopy or wooded edge; a spot shaded by foliage vs. a sunfleck; and so forth.
Discussion: Discuss the “problems” and benefits encountered by an organism in each (e.g., a leaf in shade experiences higher moisture and less overheating but less sunlight than leaf in sun—they will discuss what a leaf does—etc.; a spider in full sunlight might encounter a greater density of potential prey than one in shade, but also a worse microclimate).
11. Diurnal Change in Microclimates
Question: How do the physical stresses change over the day?
Season: as above.
How To Do It: Same as above, but on a sunny day pick a particular microhabitat (e.g., grassy lawn) and sample three times: at beginning of school, at lunchtime, and at end of school day.
Discussion: Are there any changes? Graph. How might these affect, or be used by, an organism living there? If an organism preferred one set of conditions but not others, what could it do if it were a plant? a small invertebrate? a large invertebrate or small vertebrate? etc.
12. Fire and Ice
Question: How do the physical stresses change over the year?
Season: A (by necessity!).
How To Do It: Same as #11, but sample at same time of a sunny day “typical” for that season every week throughout the school year. Graph results and discuss.
Discussion: How might these changes in heat, light, and moisture affect, or be taken advantage of by, an organism living there? What can an organism that prefers one set of conditions over another do? if it is a plant? a small invertebrate? a large invertebrate? a small vertebrate? etc.
13. On The Level
Question: Do different kinds of web-building spiders occur at different heights in the vegetation, and why?
Season: F (late S).
Framework: I.2.b. (I.3.c.ii, II.5.a., II.8.a).
Needed: A woodsy or at least shrubby edge; a meter (yard) stick or other measuring device.
Background Information: Start with brief talk about spiders and spiderwebs. Note that there are many, many web builders, building webs that vary widely in shape, size, orientation, strength, etc. See Handbook pages 55-58, also the Golden Guide to Spiders and Their Kin.
How To Do It: Then go to site and look very carefully for webs from the ground up. It’ll be ideal if each web tallied has a spider in it, but if webs are abandoned (perhaps by the spider fleeing the onslaught of student researchers) at least they can be recognized as belonging to one or another kind. You don’t need to give official names to different spiders/webs, just make up names for them, but keep these consistent.
Measure the height of each web from the ground. Make a qualitative note of the kind of vegetation at that height (grasses and herbs, weeds, shrubs, tree branches) and the orientation of the web (vertical, horizontal) as well as the size and strength of the web (flimsy film, delicate web, very strong and huge web, etc.) and any carcasses found in it. Graph web height vs. web type.
Discussion: Discuss the observed results. Why might flimsy horizontal “sheet webs” be mostly near ground? stout robust webs with large inter strand distances up high, between branches? Etc. Do spiders spin webs at different heights “to avoid competition,” or just because the vegetation has a different structure at different heights (look at your qualitative notes on the vegetation type at that height)? Do spiders at different heights catch different prey? Etc.
14. The Right Angle
Question: Do different spiders orient their webs differently, and why?
Season: Fall (late Spring).
Framework: I-3-ii (I-2-A, II-5-A).
Needed: Does not require a woodsy edge, just a weed thicket or border or some unmowed area likely to have a diversity of spiders; a meter (yard) stick or other measuring device.
Notes: Very similar to #13, but might suffice as a separate activity.
How To Do It: Again, look for webs of different species, and note which ones are horizontal, which vertical, which in between; note other characteristics of webs such as inter strand distance, vegetational support, etc. For vertical or nearly vertical webs, note whether oriented parallel or perpendicular to edge of vegetation stand.
Discussion: Should be obvious—why are webs oriented the way they are? Does that particular orientation increase prey capture for that particular web type? Do differently oriented webs capture different kinds of prey (in particular, does a sheet web capture large active fliers or tiny passive drifters/droppers, as opposed to a vertical orb web)? What’s the flight direction of insect prey nearing a vegetation edge? Etc.
15. The Right Place
Question: Are spiders in some habitats more successful in capturing prey than their colleagues in other habitats?
Framework: I-2-A. (I-2-B, I-3-C-ii, II 5-A, many others).
Needed: A common orb weaver that occurs in two or more habitats in school grounds (e.g., field vs. forest edge, or forest edge vs. forest interior). Good bets: orchard spider (Leucage venusta), garden spider (Argiope aurantia).
Background Information: Handbook pages 55-58. Note that some species (e.g., garden spider) allow carcasses to accumulate in webs for at least a day, often longer, whereas others (e.g., orchard spider) snip out carcasses as soon as they’re finished with them. Thus, spider success can be assessed either by counting corpses in webs, as in the first case, or by counting the percentage of webs that have any prey or carcasses at all, as in the second case. In any event, stick to a single kind of spider.
How To Do It: Simply examine webs in two habitats, and compare hunting success.
Discussion: What are some possible reasons for differences in success (are webs in one habitat easier to see, hence avoid, than webs in another? is wind stronger in one habitat than another, hence either making webs easier to see as they sway or the opposite, blowing prey insects into them despite efforts to escape? are there simply more prey in some habitats than others?).
Extension: If you really wanted to get carried away, you could (re )introduce the concept (but not necessarily the name) of statistical inference, noting that you really need a large sample of webs before you can distinguish a “true” difference.
16. History Rings
Question: How is the history of your campus or backyard reflected in the pine trees in it or nearby?
Season: All year.
Framework: I-2-E. (III-14)
Notes: This will work in some, but not all, settings.
Background Information: (See Handbook entry on pages 17-19).
Longleaf pine (Pinus palustris): The site probably used to be a sandhill (high pine/ turkey oak, the premier building site in Florida. Any longleafs remaining are relicts of a vanished community consisting of a scattered overstory of longleaf pines, scrubby turkey oaks (Quercus laevigata) and other small oaks, seedlings or saplings of longleaf pines in various stages, and a sparse but very diverse herb understory. Fire swept through every year or two, as litter accumulated, and burned off above ground parts of everything but thick-barked pines and palmettos. These habitats were first logged, in mid 19th century, then exploited heavily for agriculture and building. If a longleaf persists, examine it for “catfacing,” sign of turpentiners in early part of this century.
Slash pine (Pinus elliottii): Probably a former pine plantation, put in where either sandhill or hammock once existed. A tipoff for a former pine plantation is if the pine trees seem to be in rows! Some newer schools may have been built in the former chief habitat of slash pine, flatwoods, but before this is possible, the standing water must be drained off the land somehow.
Spruce pine (Pinus glabra): Used to be a mesic hammock.
Loblolly pine (Pinus taeda): Possibly formerly a farm or cattle pasture.
Sand pine (Pinus clausa): Used to be scrub, one of Florida’s most interesting habitats, but now endangered by development.
How To Do It: Students look for pine trees, identify them, and use what they know about the pine’s ecology to interpret the history. Also, as noted above, certain traits of longleaf and slash pines can give additional information.
17. History in Junk and Debris
Question: Is your backyard’s past history revealed in human artifacts?
Season: All year.
Notes: See field guide entry on Artifacts.
How To Do It: Students search the campus for all sorts of human artifacts at least a year old. Interpret history in terms of these. These could range from Indian artifacts (chert chips can be found in the vast majority of schoolyards, on campuses, and even in some backyards) to old walls, nails, fences, charcoal, etc.
18. A Fruit for All Seasons
Question: How do densities, diversities, colors, sizes, and other traits of fleshy fruits change with the seasons, and why?
Season: All year (necessary).
Framework: I-2-D (II-6-A).
Needed: Woodsy or shrubby edge, data table paper, pencil and eraser. Flagging tape might help.
Notes: This activity requires a brief 5 or 10 minute period at least every two weeks.
How To Do It: Beginning with the first week in Fall, class establishes a “transect” along a woodsy or shrubby (shrubsy??) edge of campus (so, this won’t work at all schools). You might want to mark your transect with flagging tape. Along the transect, note the locations of fruiting shrubs. Identify them, or at least give them names that will be kept standardized. Look at fruit color; squish the fruit and see how many seeds it has inside. Measure fruit diameter.
So, for each session you will have a record of how many (and which) species are in fruit, the number of individuals of each, and the total number of fruits in each. You’ll also have, for each species, information on color, pulpiness, wetness vs. styrofoam like character, number of seeds, and fruit diameter.