Main

Insects on Princeton’s Campus: A Microanalysis

| Thu, Jan 07, 2016, 4:14 AM



Main
A spider's leg joint, covered in tiny hairs
A spider’s leg joint, covered in tiny hairs

Upon assembling our Foldscope, Patrick and I set off to explore the many microcosms on the Princeton University campus.  Initially looking into the differences in leaf composition, we gathered and photographed a variety of different plant species.  The images below of a pine needle, dried maple leaf and a blade of grass, respectively, though engaging, did not really pique our curiosity as much as we’d hoped.

FullSizeRender-2

FullSizeRender

A blade of grass

In order to try to maximize the Foldscope’s potential, we thought to image insects.

Quick Sidebar: Last winter, living in the Princeton dorms as a sophomore I had a lady bug invasion in my bedroom.  I mean these things were EVERYWHERE.  I woke up with as many as ten on the ceilings alone and many more in the mounted light fixtures. After removing some from my immediate room, I realized that these insects lived in the lights and many dried shells of dead individuals had collected in the lamps.

Instead of trying to catch and image live bugs and knowing the story above, Patrick suggested that we simply look in the indoor dorm lights for ladybugs or other dead insects.

What we found was a carcass of a small spider and the dried shell of a lady bug.  The lady bug shell was no longer the characteristic firetruck red color, but it still exhibited the dark spots that we all admired as little kids.

A lady bug's spot
A lady bug’s spot

The points that we thought really made this image, were both the dark tendrils that trace across the shell’s surface and the darker pigment spots.  These observations raise the questions: How is the shell put together? Scales possibly? Or what purpose do the tendrils serve? Further, are the dark spots involved in the spot’s pigmentation? Or are they simply depressions that show up darker on camera?

Secondly, we looked in depth at the leg of a small house spider as seen at the beginning of this post. Patrick and I were both fascinated by both the very long hairs on the legs but also with the complexity of the leg joints.

A house spider's "hip-like" joint
A house spider’s “hip-like” joint

The dark and light hairs on a house spider's leg
The dark and light hairs on a house spider’s leg

Though the first picture is slightly blurry, you can see the body of the spider in the upper left hand corner, and its leg branching down to the right.  But there seems to be two joint-like structures that connect the limb, one on the topmost part of the leg and one attached to the body itself.  How are these attached? And without any bones, how similar is it to a human hip?

In the second picture, we really wanted to know if color or length determined the spider’s use of each individual hair. Are the long ones used for improving the sense of touch, while the short ones help more with retaining body heat?

Evidently, our knowledge of these small insects is lacking, but the images gleamed from the Foldscope exposed us to a tiny world, which in the past we had never seen nor thought about.

We conducted this project as part of Professor Pringle’s EEB321 class at Princeton University.



Locations



Categories

Type of Sample
microorganisms
Foldscope Lens Magnification
140x

Comments