Connected on 2012-11-05 10:30:00 from Pottawatomie, Oklahoma, United States
- Bugscope Team I'm sorry we had our own problems with the correct time.
- Teacher No prolem. We will be ready when you are.
- Bugscope Team okay sample is in the 'scope and pumping down
- Bugscope Team a second ago you could see me putting the sample in
- Bugscope Team I'll put the detector back on CCD so you can see the inside of the vacuum chamber again
- Bugscope Team now you can see the sample inside the microscope vacuum chamber
- Bugscope Team we're waiting for the chamber to reach an adequate vacuum to start the electron gun
- Teacher What type of insect are we looking at first?
- Bugscope Team it will go fairly quickly because the sample has been in a desiccator
- Bugscope Team there's a true bug, mosquito, moth, rolypoly, tobacco hornworm larva (caterpillar), some flies, a beetle
- Bugscope Team when the beam comes up in a sec I will need to do some adjustments
- Bugscope Team you'll be able to watch from there
- Bugscope Team I need to ensure that the electron beam is centered..
- Bugscope Team so the large true bug...
- Teacher Is this the abdomen?
Bugscope Team this is the back of one of the claws
- Bugscope Team tip of the proboscis
- Bugscope Team you can see that this is a leaf mimic
- Bugscope Team please let us know as you have questions
- Bugscope Team Joe is here and can handle questions while I move around the sample stub
- Teacher Can we control this view now?
- Bugscope Team yes if you would like you may control now
- Bugscope Team you can see the compound eye
- Bugscope Team with all of the facets, called ommatidia
- Bugscope Team you have it nicely centered
- Teacher My students are interested in a close up view of the eye.
- Bugscope Team you can bring the mag up now
- Bugscope Team some ants have very simple compound eyes
- Bugscope Team you can see some moth scales on the surface of the eye
- Bugscope Team please let us know whenever you have questions
- Teacher They want to know if each lens sees the same thing or if they get a panoramic view of the world?
- Bugscope Team some moths and wasps (ants are related to wasps and bees) have as many as 17,000 ommatidia per eye
Bugscope Team it is my understanding that the images are processed in the brain into a panoramic view
- Bugscope Team compound eyes give their owner a better peripheral viewing capability, and also -- importantly -- they update constantly quickly so that the insect can detect motion very quickly
- Teacher What is the darker part we see in the eye?
Bugscope Team that is a place where there was some kind of debris before the sample was coated with gold-palladium; the debris came off after coating and left that shadow
- Teacher Explains why flies are hard to catch!
Bugscope Team yes plus they have lots of mechanosensory setae that help them sense the wind from your hand
- Bugscope Team ants have built-in combs on their forearms that help them clean their antennae
- Bugscope Team and this ant would have been cleaner when it was alive
- Bugscope Team it has a cool set of serrated mandibles
- Teacher They are interested in focusing on the mandibles.
- Bugscope Team you can see that one of the antennae is broken completely off
- Bugscope Team they can cut like scissors, like pinking shears
- Bugscope Team leafcutter ants have similar serrated mandibles
- Teacher Are those sensory hairs on the mandibles?
Bugscope Team yes they are
Bugscope Team they most likely help with sense of touch
- Bugscope Team we are often surprised at how hairy insects are, but it makes sense -- they have an exoskeleton and need to have setae that project through it in order to sense their environment
- Teacher What is their function?
Bugscope Team they can help with the sense of touch. It's hard to feel anything through their tough shell. So to help the insect know when it is brushing up against something, or in this case chewing into something, they have these hairs to help
- Bugscope Team having an exoskeleton rather than an endoskeleton like we do is like wearing a suit of armor
- Bugscope Team some of the hairs (setae) are thermosensory, and some are chemosensory
- Bugscope Team some of the spines or bristles are used for proprioception -- for self sensing.
- Bugscope Team you can see another moth scale -- it looks like a small leaf
- Teacher That does make sense due to the fact that they would not have skin receptors like we do.
Bugscope Team yes!
- Teacher We are taking a better look at the antennae
- Bugscope Team ants have a straight, unbending portion of the antenna right after it comes out of the ball and socket joint we see now, whereas wasps have more continually flexible antennae
- Bugscope Team ants -- almost of them we see are female -- get most of their information from other ants, for example, via chemical signals that are most often picked up by the antennae
- Bugscope Team you can see now that this ant also has ocelli -- simple eyes -- on the top of the head
- Teacher Is there a reason why the wasp has a more flexible antennae?
Bugscope Team the wasp needs to be able to fold its antennae to get into the hive, if it has a hive, and also likely for better streamlining when it flies
- Bugscope Team this is an uncommon ant with its very sophisicated compound eyes and ocelli as well
- Bugscope Team it seems like most insects with ocelli are flying insects
- Bugscope Team the background we see now is silver paint we used to help the ant stick to the stub
- Bugscope Team I am at the 'scope and can move it fairly quickly to what we are talking about.
- Bugscope Team you can see that the ant has three ocelli
- Teacher The simple eye is on the top of the head. Is there a reason for that? You often see them near the compound eye.
Bugscope Team it's at the top of the head where it can detect light. There are usually 3 and are usually on flying insects only. They are called ocelli and help with navigation by reading the direction of the sun
- Bugscope Team the cephalotes ants have them on the tops of their heads as well, so they can detect predators that might be entering the tunnels they are guarding with their big wide heads
- Teacher A student wants to know if the lines we see on the surface of the head are unique to a species. Kind of like a fingerprint?
Bugscope Team they may indeed differ in some ways between species
- Bugscope Team they can be different between species. Some will be more pronounced or more wrinkly. Other species may have more hair.
- Bugscope Team because they are so fine and most entomologists do not use electron microscopes, the characteristics they use generally use for species keys will likely use other features
- Teacher Would they be different between individuals or between genders?
Bugscope Team they can be different between different castes of ants, likem soldiers, workers, etc.
- Teacher Can we view the mosquito now?
Bugscope Team here it is
- Bugscope Team we can tell from the antennae that this is a female. females are the ones that bite.
- Teacher They are very interested in the mouthpart.
- Bugscope Team we can see the exterior of the proboscis coming up toward us, bottom right
- Teacher What do male antennaes look like?
Bugscope Team they're fancy, complex
- Bugscope Team they have cutting mouthparts that are like steak knives. Another mouthpart will inject an anticoagulant into the cut to keep the blood from clotting. Then she will quickly fill up on her blood meal
- Bugscope Team the cutting mouthparts form a fascicle that has four cutting blades, a siphon tube with two chambers in it, and another piece
- Bugscope Team here there is a lot of juju right at the tip of the proboscis
- Bugscope Team the fascicle is inside this
- Teacher What is the function of the scales on the proboscis?
Bugscope Team with insects that have scales, one primary function is to keep them from getting caught in spider webs
- Teacher Do those hooks grasp the skin?
Bugscope Team they are likely, some of them, chemosensory/thermosensory
- Bugscope Team some may be CO2 detecting
- Bugscope Team moths, butterflies, silverfish, mosquitoes, and few other insects have scales
- Bugscope Team the proboscis is a sheath that is slit down one side so that the fascicle can come out
- Bugscope Team yes they do!
- Teacher They look like ruffles!
Bugscope Team yes they do!
- Teacher They suddenly got very hungry! I have a strange class! :)
- Bugscope Team the ridges make the scales more rigid, but not for picking up dip without breaking\
- Bugscope Team need some dip to go with those ruffles
- Teacher Can we go back to the head and antennae.
Bugscope Team now we see one of the eyes, with all of the rounded ommatidia, and we also see the base of the antenna, called a pedicel
- Bugscope Team plus the antenna is coming up toward us; its more utilitarian, not as pretty as those of a male
- Teacher Are those scales above the antennae?
Bugscope Team yes! here we can see them better
- Bugscope Team scales are modified setae themselves
- Teacher We are almost out of time. Can we see the caterpiller?
- Bugscope Team there we go!
- Bugscope Team Caterpillars have a lot of simple eyes and no compound eyes
- Teacher Does it have limited peripheral view?
Bugscope Team most likely yes since the eyes don't wrap around the head like most compound eyes do
- Teacher This has been a great experience! Thank you so much!
- Teacher The appendages look like they are meant to grasp branches.
Bugscope Team yeah they are perfect for that. Their hind likes are really just a bunch of hooks, so they are great for hooking into the leaves and branches/twigs. They help keep them rooted
- Bugscope Team Thank you for all your great questions!
- Bugscope Team I hope you and your class had a great experience
- Teacher We did. We all learned something new!
- Bugscope Team that is great to hear