Connected on 2013-01-14 09:30:00 from Jefferson Davis, Louisiana, United States
- Bugscope Team sample is pumping down...
- Bugscope Team we are ready to roll..
- Bugscope Team this is a female housefly
- Bugscope Team Good morning, Ms. Matte!
- Bugscope Team Welcome to Bugscope!
- Bugscope Team You have control of the microscope now, as you can see.
- Bugscope Team please let us know whenever you have questions, of course
- Teacher Good morning!
Bugscope Team Good morning!
- Bugscope Team the bright things that are now centered are the bases of the fly's antennae
- Bugscope Team they're bright because they're charged up with electrons
- Teacher Students are not in my classroom just yet. They'll be entering in about 15 minutes. just trying out the controls
- Bugscope Team super cool
- Bugscope Team you should be able to click on any of the presets on the lefthand screen, and the 'scope will drive to that position
- Bugscope Team below the lobes of the antenna bases you can see palps in the fly's mouth area
- Bugscope Team you can also, now, see the detail of the compound eyes -- you can see the ommatidia
- Bugscope Team the sponging mouthparts are covered with dried goo
- Bugscope Team that's why they look like they're dirty -- they are dirty
- Teacher Students say "EWWWW"
Bugscope Team haha yeah it is kind of gross
- Teacher They also want to know that if the antenna have an electrical charge, then could they shock you?
Bugscope Team it is such a small charge... when we vent the microscope it will go away -- it will go to ground
- Bugscope Team you can see that one of this centipede's antennae is broken off
- Bugscope Team now we can see that antenna
- Bugscope Team if the antenna was still in place we would not have been able to see the compound eye
- Bugscope Team the bumpy things we see on the bottom help the centipede lock its prey against its mouth so it can bite
- Bugscope Team now we've moved up, of course, and we see crossed palps (accessory mouthparts) plus the top of one the mandibles, plus of course the compound eye, which has only 20 or so facets, also called ommatidia
- Teacher Students want to know what the little hairs are used for and what are they called?
Bugscope Team they are called setae (pronounced see-tee). they help the centipede feel what is going on around it- kind of like cat whiskers
- Bugscope Team this stinger has a very long shaft, and it is also flexible. since we made the stinger preset, the stinger moved over, and we just found it again.
- Bugscope Team the edges of the stinger are serrated like a steak knife and help the wasp insert it into its prey
- Bugscope Team insects and comparable arthropods like centipedes and spiders do not have skin, and they do not have bones inside them like we do. Instead, they have what is called an exoskelelton -- a skeleton on the outside of the body. That is made of chitin, and it is a shell, like a shrimp shell.
- Bugscope Team 'exoskeleton'
- Bugscope Team because insects have a shell, kind of like if we were wearing armor, they need to have the setae Cate mentioned, and those we see here, to help them sense their environment
- Teacher Students want to know are these setae as well?
Bugscope Team yes they are!
- Bugscope Team setae can be mechanosensory -- to help sense touch and vibration and wind
- Bugscope Team setae can also be chemosensory, meaning that they can be used to smell the air or taste things by touching them
- Bugscope Team and setae can be thermosensory, giving the insect/arthropod the ability to sense hot and cold
- Teacher Can they bite?
Bugscope Team i think when they see us, their first instinct is to scurry away. If we tried to get them to bite us I don't think it would work because their mouthparts are so small
- Teacher What do they eat?
Bugscope Team starch amd sugars, mostly
- Bugscope Team they like the starches that are found in bookbindings, and that is why one reason we see them in houses so often
- Bugscope Team Lepisma saccharina is one of the silverfish genus species names. It tells us that the silverfish likes sugar.
- Bugscope Team with some flies, like this one, we can tell the difference between males and females
- Bugscope Team in many fly species, the eyes of the females are far apart, like in this fly
- Bugscope Team the eyes of male flies are close together, sometimes almost touching
- Bugscope Team this fly has sponging mouthparts
- Bugscope Team when it lands on something it might want to eat, it can taste it using some of its chemosensory setae, like those on its palps, which are accessory mouthparts
- Bugscope Team they vomit out digestive juices and then sponge up the resulting digested liquid
- Bugscope Team here we can see the sponging mouthparts, and we see ridges, beneath the dirt, that have muscles beneath them that allow the mouth to move and to sponge up liquids, as Joe said
- Bugscope Team some flies, like deerflies and horsesflies, have slashing/cutting mouthparts
- Bugscope Team They're probably cleaning their legs so that the chemosensors on them are clean
- Teacher Students want to know why they rub their front legs together after landing on your food?
Bugscope Team I think it is because they want to keep their legs clean. at the ends of the legs are claws, and near the claws are pads called pulvilli -- a single pad is called a pulvillus. the pulvillus has lots of what are called tenent setae on it that allow the fly to stick to vertical surfaces
- Teacher The eyes look like speaker covers!
Bugscope Team haha Yes they do!
- Teacher Also, is the eye distant the only way to tell from first glance male/female?
Bugscope Team some male flies have more feathery antennae, whereas females have simpler antennae
Bugscope Team some also have distinct external genital features that are different between the sexes
- Teacher What are the black specs on their eyes?
Bugscope Team if you take the magnification up you can probably see what those specs are
- Bugscope Team sometimes it is just dirt, and sometimes it is pollen; sometimes we see scales from moths or butterflies or silverfish on the surfaces of the eyes
- Teacher So are they shedding/
Bugscope Team could be!
- Bugscope Team they look like little flakes of something, don't they?
- Teacher Looks like fur on the edge of the eye
Bugscope Team the microsetae form what looks like fur. that is called the vestiture, kind of the 'dressing' of the head
- Bugscope Team this moved as well from the time we made the preset
- Bugscope Team it is a small spider that was for some reason on the centipede's body
- Teacher What are we looking at?
Bugscope Team the thing pretty much in the middle is a spider -- you can see where a lot of legs are missing
- Bugscope Team the larger thing with the armored-looking segments is the lower body of a centipede
- Bugscope Team this is cool
- Bugscope Team we can see the beetle's mouthparts quite well here
- Bugscope Team the jagged curve in the middle, top, is the division between the mandibles, which open left and right like a gate
- Teacher Explain the mouth parts please
Bugscope Team there are 2 sets of palps- a pair of short ones sticking out and a pair of ones that are curving around. The palps help the beetle taste or move around food
- Bugscope Team so palps are accessory limbs, like small extra legs that help the insect feed
- Bugscope Team the tips of the palps often have little nubs on them that function like tastebuds on your tongue
- Teacher What are the beak looking parts?
Bugscope Team those are the mandibles - the jaws. they are closed together right now
- Bugscope Team so they are very much like the halves of a beak, but they open left and right instead of up and down
- Bugscope Team they are made of chitin, and often they are hardened with minerals like zinc or calcium
- Teacher What species of beetle is this?
Bugscope Team we are not sure about this. Joe thinks it might be a rove beetle, but it is hard for us to tell
- Bugscope Team the things we are looking at now are moth scales
- Bugscope Team I am sitting at the microscope -- the SEM
- Bugscope Team scanning electron microscope
- Bugscope Team so sometimes I 'help' with driving
- Bugscope Team moths, butterflies, silverfish, mosquitoes, and few other insects have scales
- Bugscope Team they are actually setae, modified into a fan shape
- Teacher Why do they have these scales between their eyes? What is the purpose?
Bugscope Team one thing scales do is help the insect escape from spider webs
Bugscope Team the area between the eyes are the palps, and other moth parts, so it's most likely that the scales are there to protect the structures.
- Bugscope Team they come off very easily -- they are the 'powder' that comes off a butterfly's wings when we rub them
- Bugscope Team they provide color, in two forms, and they likely help the insect regulate its temperature as well, plus on the wings they seem to function sort of like feathers do on a bird
- Bugscope Team ew but cool Joe
- Bugscope Team scales form the colors we see on butterfly wings. some of the color comes from pigment, and some comes from the shape and size of the tiny ridges that form the shape of the scales
- Teacher Why do moths eat our clothing?
Bugscope Team wools is just another dead animal skin/hairs, and that's what the clothes moths are eating
Bugscope Team clothes that are made from cotton, silk and synthetic fibers won't have this problem
- Teacher So they eat other animals?
Bugscope Team yeah, i guess you can say that. They're an important part of nutrient recycling in nature, but they just happen to be considered as pests for humans since we use furs and wools for clothing
- Bugscope Team insects and similar arthropods, as well as large animals, are opportunists, and if there is something they can eat, some animal will be doing that
- Bugscope Team true story.
- Teacher One class is ending, and another beginning. Will be done for a few minutes while classes switch
- Bugscope Team ok
- Bugscope Team ok thanks for letting us know
- Bugscope Team hello!
- Bugscope Team Cool! Welcome to Bugscope!
- Bugscope Team this is a beetle we have not been able to identify
- Bugscope Team here is a wasp
- Bugscope Team really interesting mandibles
- Bugscope Team they don't quite join together
- Teacher *the
- Bugscope Team a lot of insects only live for a month or two
- Teacher Do they setae die like our hair?
Bugscope Team once an insect loses its setae, they generally do not grow back -- if the insect is an adult
- Bugscope Team now we see the compound eyes
- Bugscope Team this wasp has a super long stinger that is also, as they often are, an ovipositor
- Bugscope Team most wasps and bees and ants you see are females
- Teacher Can you tell male/female by the distance of the eyes on wasps as well?
Bugscope Team that trick does not work with ants, wasps, and bees, which are all related.
- Bugscope Team but as Cate says, almost all of the ones we see are females. Anything with a stinger is a female.
- Bugscope Team here we see the serrated edges of the stinger that help it cut into the body of its prey
- Teacher What do wasps eat?
Bugscope Team they eat a variety of things: some like sugar, or nectar from flowers
Bugscope Team yellow jackets are important predators of insects, and they also will eat most things, meats, fruits, whatever.
- Bugscope Team wasps with super long ovipositors/stingers like this often attack caterpillars, and the long stingers allow them to stick past the 'fur'
- Teacher What are stingers made of?
Bugscope Team they are made of hardened chitin like the mandibles; chitin is what the exoskeleton
Bugscope Team the stinger is actually a modified ovipositor, no longer used for egg laying, but rather associated with releasing poison instead.
- Bugscope Team 'what the exoskeleton is made of' I meant to say earlier
- Bugscope Team hey this is cool
- Bugscope Team there is a tiny flying spaghetti monster on the surface of the silverfish's exoskeleton
- Bugscope Team it seems to be a kind of plant that flies through the air
- Bugscope Team silverfish are covered with scales that give them that silver appearance
- Bugscope Team the scales are loose, as in butterflies, moths, and mosquitoes, and they get stuck to spiderwebs and allow the insect a better opportunity to escape
- Bugscope Team this is the housefly
- Bugscope Team the top branched portion of the antennae is called the aristate antenna
- Bugscope Team the bottom portion of the antenna is lobed
- Teacher How many eyes do they have?
Bugscope Team they have two compound eyes with perhaps a few thousand ommatidia, and they have three simple eyes on the top of the head, called ocelli
- Bugscope Team some large wasps have as many as 17,000 ommatidia per compound eye
- Bugscope Team these are the fly's sponging mouthparts
- Teacher how did it get its name?
Bugscope Team they are called silverfish because of their color, silvery grey or blue, and because they have a sort of fish-like movement
- Bugscope Team there is a lot of dried liquid on the mouthparts, and it is hard to see the spongy portions, but you can see the ridges in some places
- Bugscope Team Now we see one of the compound eyes, and the furry part to the left (we cannot see it just now) is called the vestiture
- Bugscope Team the individual facets of the compound eye -- the lenses -- are called ommatidia
- Bugscope Team having compound eyes gives insects, often, better peripheral vision because of the dome shape
- Bugscope Team this is something we have never seen before, and we are not sure just what it is
- Bugscope Team also, compound eyes have an advantage over eyes like ours in that they are much more sensitive to changes in the visual field, meaning that they register motion much more quickly
Bugscope Team however the resolution of the image is a lot lower.
- Bugscope Team this is the mouth of the centipede
- Teacher Explain the parts of the mouth please
- Bugscope Team the tooth-like elements help hold the prey so the centipede can pierce it with its mandibles
- Bugscope Team just above those are the mandibles, pointy and closing side to side
- Bugscope Team the mandibles are kind of more like fangs here and they are curving into the mouth opening
- Bugscope Team and above those are two palps
- Bugscope Team centipedes inject venom into their prey to kill/immobilize them
- Teacher can they bite us?
Bugscope Team they can, and especially the large ones in the Tropics
- Bugscope Team they are venomous, but as Scott (as SEM) said, the ones in the tropics are the dangerous ones to humans
- Bugscope Team this is a rove beetle
- Bugscope Team mostly what we see here are mouthparts, again
- Bugscope Team with the 2 sets of palps it has, it kind of looks like there is an insect trying to climb out of its mouth
- Bugscope Team ants often look like that as well
- Bugscope Team rove beetles are mostly predators of other insects
- Bugscope Team the black stuff looks like some liquid is dried all over it
- Teacher What are the black holes all over its body?
Bugscope Team if we look at them up close I think we will see that they are small particles, or as Cate says, dried liquid
- Bugscope Team they appear black because they are kind of oily, and the blackness is where they are absorbing and not emitting electrons
- Bugscope Team the specimens we are looking at today are in the vacuum chamber of the scanning electron microscope (SEM), and the images come to us as electrons are scanned across the surfaces of the insects/arthropods
- Teacher Why do they have a cracked appearance?
Bugscope Team the cracks are in the surface of the cuticle, or chitin -- what the exoskeleton is called; the cracks show us how the cuticle formed
- Bugscope Team the exoskeleton is made of a protein similar to what our fingernails are made of
- Bugscope Team we see those cracks in part because some of the oily goo on the surface has run into them and highlighted them
- Bugscope Team it gives us an idea of how the protein formed into tiny interlocked segments and became the exoskeleton
- Bugscope Team thank you!
- Teacher Our class period is ending. Thank you so much for taking time out of your day to answer our questions!
Bugscope Team Thank you, Ms. Matte!
- Bugscope Team Thank you for connecting with us today!
- Bugscope Team Thank you! See you next year!