This was bizarre. We had recently bought a trailer, and I took it to Cape Cod for a birding retreat. At one point I went to check on the propane tanks, and noticed that the adjacent motor for raising and lowering the tongue jack was crawling with tiny critters. Looked closer, and found that they were globular springtails, dozens of them! What about this location was such a magnet for them? Were they just drawn to a high point, like hilltopping butterflies? Or were they drawn to some quality of the motor, or maybe the smell of the propane? I also noticed a variety of sizes and colors; I am putting these photos under the heading of the species that appears to match the most distinctly marked individual, one of the two in this photo. Is it safe to assume that the others are different age classes or sex of the same species?