Table salt hopper crystal (3.2 Mb image)

The campus is surrounded a row of Norwegian spruce which pollenate heavily in the spring.  It's amazing to watch, but also annoying to people with pollen allergies. The image is pretty dark because it is uncoated and also probably because I the lab monitors set too bright.  (6.7 Mb image)

The pollen disperses in the wind (as opposed to being transported by an insect, etc.).  For this reason, the pollen has two "wings" called sacci to help carry it on the wind.  (1.7 Mb image)

The surface of the body ("corpus") has a knobby texture - maybe to help it catch the wind, too?  (1.9 Mb image)

Dakota Pittinger – nicknamed “Paleo McConaughey” because he has an encyclopedic knowledge of dinosaurs/paleontology and he looks like Matthew McConaughey – obtained a sample of spherules from the K-Pg boundary.  The spherules in this sample rained down on the seafloor (a quiet environment that’s great for preserving them).  The seawater reacted chemically with the glass, though, forming tiny crystals of clay that make these surfaces rough. .
(amazing drawing by Claus Lunau)

Individual spherules appear to have an inner core and outer shell.  I suspect the outer shell is the depth to which seawater altered glass to clays at the time of deposition, and the core was still glass.  That boundary would have been the limit of chemical reaction.
(8.2 Mb image)

The cores pop out, leaving the platy clay shell.  You can see the plates of the clay minerals on that inner surface, too.  The smooth surface on the top left of the shell is where we accidentally smashed the sample when mounting it onto the sample stub.  Isn’t it amazing to think that 1) rock can vaporize into gas, and 2) rock vapor condenses like dew into glass beads that rain down onto the Earth?  It’s an amazing world!
(9.4 Mb image)

Whole diatom - roughly 30 μm long (roughly one thousandth of an inch) surrounded by debris of broken other frustules.  The broken frustules are like microscopic broken glass, which gives diatomaceous earth its pesticide properties – harmless to giant humans, but tough on insects. (9 Mb image) 

These frustules connected with one another with an interlocking join (see middle of whole frustule image).  At this magnification, you can start to see the microporous texture of the surface of the frustule, too, which helps give diatomaceous earth it's absorbent characteristics. (9 Mb image) 

Having a body of transluscent quartz is great for protection and letting light in for photosynthesis, but quartz is waterproof and gasproof, so the diatom needs a way to let CO2 into the frustule and let O2 gas out.  The pores (areolae) have a fine mesh of quartz that prevented even the tiniest of predators from getting into the cell.  Is it any wonder that we use diatomaceous earth for filtering contaminants to make safe, clean drinking water? (9.4 Mb image)

Front end

Low magnification "yearbook portrait" of the ant that give its life for this exploration.  (17 Mb image)

Back end (acidopore?)

Everyone's got one.  This is this particular ant's rear end.  Some ants have stingers, others have acidopores (from which it can spray formic acid).  The claw at the top of the image is one of its six feet. (17.5 Mb image)

My kids have a running joke that whenever a bug gets in the house, or we find a weird piece of metal or dead animal body part or ... almost anything that might be interesting to explore microscopically, they look over at their dad and ask if it's going into the SEM.  Since they're right more than half the time, I can't argue.  This sample was an an I found crawling on our kitchen counter. (16.9 Mb image)

This image of the eye of the ant shows one of our early attempts with the metal sputter coater - a tool we use for depositing an ultrathin layer of gold on the surface. (Please click here to learn more.)  The gold makes the surface electrically conductive and also emits more electrons when hit by the electron beam (giving us a brighter signal).  The dark lines between the facets of the eye are where gold did not deposit well. (7.4 Mb image)

This is a low magnification image of the jaws (mandibles) with an antenna coming out of the "nose hole."   I'm always fascinated by imagery of creatures at this scale because I imagine this being the norm for each species.  We might find this monstrous if we ran into something that looks like this alone on a dark night, but for other individuals of its species, this might be a reassuring face of familiarity and aesthetically-pleasing features.  I suppose we all anthropomorphize sometimes. (20.1 Mb image)

This is still just a medium-magnification image, but life's not always about doing the most extreme thing - it's about doing the thing that's right for the moment.  This is the scale that best shows the feature of interest: the wear that the ant has experienced on its jaws (mandibles) when it's chomped on hard things and "chipped a tooth." (18.4 Mb image)

The tip of one of an ant's antennae looks so much gentler than the sharp claws on its "feet." (7.2 Mb image)

Zooming in on the joint between segments of the antenna, we can see how the hairs attach, and that there are some tiny holes (maybe spiracles for getting oxygen into the exoskeleton?)  If you look at the high resolution image, you'll be able to spot a little dark gray rectangle near the center where we looked at the surface at high magnification for too long, leaving a little "burn mark." (9.4 Mb image)

We can still comfortably zoom in 10 times closer than this, but this scale shows the wavy texture of the surfaces of the shell (exoskelleton) surface and hairs (setae) nicely.  The width of this whole image is about 25 micrometers = one thousandth of an inch (7.2 Mb image)

These images are very dark and it's totally my fault.  I just patted some sticky tape on the fungus surface so spore stuck, blew off the loose excess spores, and put the sample in the SEM.  There is no gold coating, so nothing to brighten the secondary electron signal.  I used a very gentle beam with a much-too-short working distance for the detector (when the sample is too close the electrons can't get to the detector well due to shadowing). I did almost everything wrong - learning is a process. (1.5 Mb image)

My very poor sample preparation and bad sample positioning made these images too dark.  Brightness and contrast can be adjusted in post-production - these are raw - but the point here is to showcase how even poor prep can produce informative imagery.  The Gemini 300 SEM is not 100% fool-proof, but I haven't met a fool yet who couldn't get useful imagers with it. (1.2 Mb image)

The surfaces of each spore are rough.  I suspect that is to better help them be carried by the wind.  Each spore has a single stick, which might be the original structure from which they grew on the sporangium (?), or maybe they are germinating and those are the first hyphae as the spores start their new lives.  As the sign in the lab says, "Dr. Friehauf is not a biologist." (1.1 Mb image)