Connected on 2014-02-04 09:30:00
from Cook, Illinois, United States
- 8:38 am
- Bugscope Teamsample for today's session with St Matthias is pumping down
- 8:44 am
- 8:50 am
- Bugscope Teamnow we're making presets for today's session.
- 8:56 am
- 9:02 am
- 9:09 am
- 9:16 am
- 9:22 am
- Bugscope Teamgood morning!
- Bugscope Teamwelcome to Bugscope!
- TeacherGood morning! We are almost ready here.
- 9:28 am
- 9:34 am
- Bugscope Teamwe are ready to roll
- Bugscope Teamthis is a serious aphid predator
- TeacherWe are ready!
- Bugscope Teamso you have control of the microscope, and we welcome any questions you have about the insects/arthropods or the microscope or anything else
- TeacherThank you! We were just discussing aphids and were curious about the larva's mouth
- Bugscope Teamyou can change the mag, click on a part of the screen to center the image there, change the contrast and brightness, and focus
- Bugscope Teamhere we can see that the ladybug larva has a small mandible visible from here
- Bugscope Teamit also has four palps, two mandilbular and two maxillary, that help it taste and also manipulate its food
- TeacherWhat is a mandible? Is it like teeth?
Bugscope Teamthe mandible is the jaw
- Bugscope Teamin people, the lower jaw is the mandible and the upper jaw, part of the head, is called the maxilla
- Bugscope Teamwith insects the mandibles open side to side, like a gate
- 9:39 am
- Bugscope Teamthe palps have tips with chemosensors that are like tastebuds
- TeacherWhat is the actual size of a larva mandible?
Bugscope Teamwe can estimate by using the scalebar on the lower left of the screen
- Bugscope Teamit is likely about 200 micrometers long, 200 microns
- Bugscope Teama microsm
- Bugscope Teamoops
- TeacherVery cool!
- Bugscope Teama micrometer is a millionth of a meter, or a thousandth of a millimeter
- TeacherNow we are going to look at the larva's legs
- Bugscope Teammicron = micrometer
- Bugscope Teaman easier way for us to think of 200 microns is as a fifth of a millimeter
- Bugscope Teamto us, a larva is a simplified adult
- Bugscope Teamfor example its eyes are not very good, and it has single claws at the tips of its legs, whereas an adult ladybug has compound eyes and articulated claws
- TeacherBesides the wings, does a larva have any different body parts than an adult?
Bugscope TeamI think it has most of the same parts but they are to us more primitive
- 9:45 am
- Bugscope Teamlike the eyes, of which there are maybe 5 per side of the head, called stemmata, are hardly there in a larva
- TeacherVery cool
- TeacherWhat are we looking at on this side of the larva? What is the purpose of this part?
- Bugscope Teamthis is the antenna
- Bugscope Teamin the back we can see two wrinkled stemmata
- Bugscope Teamantennae help the insect sense the environment; often one of the main things they do is help collect chemical scents from the air'
- Teacherwe are going to switch images
Bugscope Teamsuper cool
- TeacherWe are interested in spiders, so we want to see the eye up close
- TeacherCan you describe what we are seeing here?
- Bugscope Teamthis is really interesting because we see the same pattern of folded setae in front of the eye on two sides of the cephalothorax
- TeacherWhat are setae?
- 9:50 am
- Bugscope Teamthe dome is one of the eight spider eyes, and the things that are like very long pine trees are plumose setae, which are vibration sensitive in this case
- Bugscope Teamsetae are the things that look to us like hairs. they are very important because the help insects and comparable arthropopds sense their environment
- Bugscope Teaminsects have an exoskeleton, which is like a shell, or like having armor. the setae stick through the exoskeleton and help with touch, wind, chemical, hot/cold, and other sensing
- TeacherWhat part of the eye is behind the dome?
Bugscope Teamthat is the lens, I guess you could say. spider eyes are often not very good
- TeacherAlso, what kind of spider is this sample?
Bugscope Teamnot sure, but probably a wolf spider
- Bugscope Teamspiders have this interesting function in which if they are bitten by another spider and sense venom entering their body, for example through a leg, they can just let that leg fall off
- Bugscope Teamnormally the plumose setae are standing up
- 9:55 am
- TeacherDo they grow a new one?
Bugscope Teamnot unless they are the kind of spiders that molt, like large tarantulas
- TeacherVery interesting
- Bugscope Teamwe are not very good with identifying spiders beyond the more obvious ones
- Bugscope Teamtarantulas have setae that are called urticating hairs that they can actually fire at something that is bothering them
- Bugscope Teamurticaria means 'itching'
- Bugscope Teambut the urticating hairs can actually get stuck in the surface of your eye
- Bugscope Teamwe can see 7 eyes here; one is obscured at the top of the screen
- TeacherWhat part of the spider is this?
Bugscope Teamthis is the cephalothorx, which is a combination head and thorax
- Bugscope Teamspiders do not have separate heads and thoraxes
- 10:00 am
- Bugscope Teamyour thorax is your chest, or your trunk
- TeacherHow can you tell which parts are the eyes?
Bugscope Teamthey are the round bumps that are kind of in a circle
- Bugscope Teamwe have done this a few times and have practice seeing them
- TeacherAre the lines on the right side the setae again?
Bugscope Teamthose are -- yes! -- setae that are lying down
- Bugscope Teamthe setae help the spider sense vibration, which is very important to it; noise is vibration transmitted through the air
- Bugscope Teamthe things that look like flat blades are scales from insects
- TeacherVery cool
- Bugscope Teaminsects like butterflies, moths, mosquitoes, and silverfish has scales on their wings and bodies, and one purpose of the scales, which are modified setae, is to protect them from spiderwebs
- Bugscope Team'have' scales on their wings and bodies
- Bugscope Teamwhen you rub a butterfly's wings, the stuff like powder that comes off is the scales
- Bugscope Teamthere is a scale lying on some of the spider's setae
- 10:06 am
- TeacherIs this a scale on the spider?
Bugscope Teamyes but it is not from the spider
- TeacherThat is very cool
- Bugscope Teamscales have ridges that make them more rigid, just like Ruffles potato chips
- Bugscope Teamthe ridges also interfere with light, with the wavelengths of light, and thus they can produce color
- Bugscope Teamthat is, they can produce both color from pigment and color from their shape, which is called structural color
- TeacherWhat are the small dots on the ridges?
Bugscope Teamsome of those are dirt, but right on the ridges we are seeing how the scale formed; those dots are part of the structure
- 10:11 am
- Bugscope Teamthis is another scale, on the head of a millipede
- Bugscope Teamsometimes some sort of liquid will get on them and dry and they will look like little numps
- Bugscope Teamwe can see that the scale is pretty small, because the millipede itself is small
- TeacherHow many legs does this millipede have?
- Bugscope Teammilli means 1000, and ped means foot, but that isn't really how many legs they have
- Bugscope Teamit should have four per segment, so we can couny segments and get pretty close to the true number
- Bugscope Teammaybe if it were a really long one from the tropics
- Bugscope Teamso there should be 40 legs among the ten segments we see here
- TeacherYes, we were just counting too!
- Bugscope Teambut the millipede was at least twice as long before it broke
- TeacherThat is a lot of legs!
- Bugscope Teamcentipedes have only one pair of legs per segment
- 10:16 am
- TeacherWhy would an insect need that many legs?
Bugscope Teaminsects have only six legs, so we know this is not an insect; but I think its a necessity of having a very long body
- Bugscope Teamso if you think about a caterpillar, then, with its own long body, and it's an insect so should have only six legs -- we find that they have what are called 'prolegs' that fulfill some of the leg function
- TeacherIt looks like the legs have joints. How many joints do millepede legs have?
Bugscope Teami think there are 6 per leg. You can try to count them by looking where it is bending
- Bugscope Teamthis is something odd we are not sure about
- Bugscope Teamusually, on insects, we find two spiracles per segment -- one on each side
- Bugscope Teamthis looks like a spiracle, but there are two on each side or four on each body segment. so it's good this is not an insect...
- TeacherWhat are spiracles?
Bugscope Teamthey are breathing ports that supply oxygen to the body. they are connected to a trachea that runs through the body
- Bugscope Teamthey dont have noses like we do and they don't breathe in their mouths
- Bugscope Teamrolypolies are similar to millipedes, but they are crustaceans, actually related to crabs and lobsters
- 10:22 am
- TeacherVery cool - we see a lot of roly polies in Chicago
- Bugscope Teamroly polies like dark damp places. You can usually find one under a rock
- Bugscope Teamwe can see that many of the insect and comparable arthropods in the sample today have scales on their bodies
Bugscope Teamit is because when we collect insects we have them in the same place, together, sometimes, so the scales get on everything
- Bugscope Teamthe part that looks like a raspberry is the compound eye of the ant
- TeacherWe also had a question about the neck of an ant - if it is connected like the spider or separated
- Bugscope Teamwe can see that the mandibles are serrated like pinking shears
- Bugscope Teamand there are lots of setae on the mandibles that help the ant sense when she is biting something
- Bugscope Teamit is difficult for us, sometimes to know where the eyes are because the antennae usually take that place on the head -- the place we would expect eyes to be
- 10:27 am
- TeacherVery cool
- Bugscope Teamthe individual facets of the compound eye are called ommatidia
- TeacherCan you tell us more about the antennae?
Bugscope Teamants, for one, have that long nonflexible component of the antenna close to the head, whereas wasps and bees, which are closely related, have antennae that are flexible much closer to the head -- the antennae are fully flexible
- TeacherDoes an ant mandible chew side to side or up & down?
Bugscope Teamside to side
- Bugscope Teamhere we see an antenna that broke off; we were hoping to find more chemosensory setae
- 10:33 am
- Bugscope Teamyou can see how the mandibles cut, side to side, maybe here
- TeacherVery cool. We had a question about the ant's feet if they have sensors too
- Bugscope Teaminsects do not have teeth, but the toothlike elements of the mandibles are hardened, often, with zinc and calcium
- Bugscope Teamthe mandibles open out like a gate
- Bugscope Teamsome insects do indeed have chemosensors on their feet; there are so many species of ants that it is likely we could find some that, like Monarch butterflies, have that capability on the setae on their feet.
- Bugscope Teamthank you for joining us for bugscope
- TeacherWe are out of time here.
Bugscope TeamThank You!
- TeacherThank you very much! We really enjoyed talking with you!
- Bugscope Teamhttps://bugscope.beckman.illinois.edu/members/2013-079 is where you can access your images and chat from today
- Bugscope TeamBye!