Entomology Test 3
What is the world’s most dangerous insect?
What are insects good for? (2 reasons)
Recycling (wheel of life)
Smallest, biggest, fastest?
WTF dong kim?
Insects are __% of all animals and __% of all species.
75, 50
What are their secrets to success? (3)
1. Adaptable Exoskeletons
2. Small Body Size
3. Short Generation time
Give one insect vector disease that affects humans? animals? plants?
Human-West Nile
Animal- Heart worm
Plant- Pierce’s diease
Name two ways the insects affect the environment.
1. Break down organic materials
2. Modify soil
3. Make some areas unlivable
4. Help/injure other elements of the ecosystem
5. Key element of many food webs
Name four characteristics of arthropods.
1. Exoskeleton, must shed to grow
2. Segmented
3. Jointed Appendages
4. Ventral Nerve Chord
5. Open Circulatory System
Lobsters, crabs- NOT INSECTS
What do varroa mites and tracheal mites do?
kill bee colonies
one pair of legs per segment
one pair of large antennae
nearly all predaceous & venomous
Two Pairs of Legs per segment
No venomous bite; noxious chemical release
How can you tell if something is an insect?
3 body regions
3 pairs of legs
compound eyes
wings (usually)
one pair antennae
Order Odonata
Chewing mouthparts
Prolonged beak
Coleoptera: Family Lampyridae
Lightning Bugs, Fireflies
Produce ‘cool’ light
Scorpion Fly (Order Mecoptera)
Head usually prolonged beak
Order: Diptera
One pair on wings on thorax
Important pests and beneficial
Order Siphonaptera (Flea)
Carry plague and parasites
Flea Life Cycle
Adults NEVER leave animal host
Eggs fall from animal, usually in resting area
Larvae usually feed on animal feces
Skippers (Family Hesperiidae)
Stouter (fat) body
Hooked antennae
Caterpillars (Lepidopteran Larvae)
Six true legs attached to thorax
usually six lateral stemmata
Order: Lepidoptera (Family: Danaidae)
Milkweed Butterflies
Monarch- feed on milkweed for protection
Monarch Migration
Spring: mate and fly north
Lay eggs on Milkweed
Summer: several generation
Migrates to Mexico, NONE RETURN
Order trichoptera (caddisfly)
Almost all aquatic as larvae
lives underwater
Order Hymenoptera (ant, bee, wasp)
Four wings, hind smaller
Chewing mouthparts
Females only stinging, work, defense
Many social as well as solitary species
male-full complement of chromosomes, come from unfertilized eggs
only chromosomes from the female parent
come from fertilized eggs
Family Formicidae- the ants
All are social insects
workers, soldiers- all female
Males live just long enough for mating
How are new ant colonies formed?
New queens lose wings and the males die.
Fire ants
bite AND sting
only females can sting
Fire ant control
2 step program
baits twice per year
mound treatments for established colonies
only one queen
Dance to direct food sources
(round/waggle dance)
African Bees- same, but more aggressive
___ stings per pound of body weight is fatal
Insect Integument
made of chitin- sugar polymer for toughness and flexibility
resilin- elastic, can store energy (grasshoppers)
Molting or Ecdysis
only immatures molt
instars-period between molt
Ecdysone-molting hormone
Digestion/Excretion (three sections)
Stomodeum- Ingestion, digestion
Mesenteron- Absorption
Proctodeum- Excretion, regulation
Makes plants/woods harder
Also in insects:
Bacteria- few Beetles
Protozoans-termites, roaches
Relies very heavily on diffusion
O2 enters through openings called spiracles (abdomen and thorax)
does not move O2
open system
blood called- hemolymph
facilitated by dorsal aorta
Central Nervous System
Neuron groups form ganglia
brain and segmental ganglia
Thoratic ganglia
controls legs/wings
Vision, integration of multiple behaviors
antennal inputs
Connects to Stomatogastric sysem; integrates input from other brain lobes
Simple eye parts (vs compound eye)
Ocelli (no images, changes in light)
and stemmata
About 1/2 of all insect species are ___________
What do insects hear with?
Insect Interactions
Mutualism (+/+)
Commensalism (+/0)
Predation/parasitism (+/-)
Competition (-/-)
Beetles are _____&_______ pollinators.
important and early
What three things do attract pollinators?
1. Odors
2. Colors
3. Nectar
Advantages of wind pollination
not dependent on third party
no need to supply ‘reward’
Disadvantages of wind pollination
decreased likelihood of out-crossing
much larger production of pollen needed
plants don’t disperse well
Advantages of insect pollination
Facilitates out-crossing, even if plants are dispersed
Helps plants colonize new habitats more rapidly
reliable dispersal facilitated plant specialization (leads to diversity)
Disadvantages of insect pollination
3rd party involved
plant must produce reward
rich in sugars
amino acids, proteins, and lipids
Nonedible pollinators rewards: Heat (2)
usually involves beetles
flowers metabolize lipids and starches
Nonedible pollinators reward: Insect Mimics (2)
flowers mimic prey (aphids attacked by wasps)
Wasps,sawflies and ants are all decieved by some flowers
Non edible pollinator rewards: Other mimics (2)
Flowers mimic other flowers that offer rewards
smells like a dead animal attracts flies
What are the costs to the pollinator?
Energy and Risks
What are the costs to the plant?
Resources to produce reward, risks of being robbed, attraction of herbivores
Pollination patterns of beetles
usually associaed with dish/bowl flowers
Pollination patterns of Flies
associated with white, smelly flowers; variation
Pollination patterns of Butterflies
long tongue, deep in flower, sweet odors, bright colors, red
(moth flowers-less color, more odor)
___ are the largest group of efficient pollinators
Name two bee adaptations for plant interactions
plumose hairs
diet of nectar and pollen
Name two plant adaptations for bees
colors in bees’ range of cvision
separate petals
Butterfly life cycle
egg (few days)
larva (few weeks)
Pupa (variable)
Adult (a few weeks)
How many described species of insects?
1 million
External phytophagous feeding patterns
consume foliage, fruit, and roots directly
suck plant juices
Mechanical Plant Defenses
spines/thornes- prevents large herbivores, not useful against insects

Trichomes-specialized epidermal cells may be straight spikes or hooks (deters feeding, slices insect cuticle)

Chemical Plant Defense
Alkaloids are very common (1/3, of plants have them (caffiene, morphine, nicotine)
What is it called when plants can withstand damage without compromising fitness?
monarch butterflies hold chemical in special tissues or structures where it cannot interfere with metabolism, and make them have bad taste against predators
Most insect species feed only within_________ plant family(s).
one. (10% feed on more than 3)
What ways can insects transmit diseases?
Mechanical-disease agent comes in contavt with feet/mouth/etc. and is simply passed along

Plant- hemiptera, thysanoptera

___% of plant diseases are transmitted by insects.
Characteristics of Parasitoids
attack various hosts, but tend to be species specific
Must find proper sites where hosts occur
Often rely on volatile cues
May use odor, sound, vibration
Charateristics of Parasites
Rare among insects (7 of 34 families)
Kelptoparasites use resources of other species
Cuckoo bee lays eggs in other bee nests
Some flies steal from spiders
Smoe spiders steal from spider
What determines carrying capacity? (biotic factors)
density dependent

competition for food, shelter, mates
natural enemies

What determines carrying capacity? (abiotic factors)
density independent


Source-sink dynamics
colonization of a habitat is affected by 3 key factors
-distance from source
-size of new habitat
-population size in source
Colonization is also affected by the dispersal ability of the organism
high reproduction, low survival
highly mobile
colonize unstable environments
weak competitors
reduced reproduction, high survival
variable mobility
colonize stable environments
strong competitors
Eusociality (3 characteristics)
1. comparitive brood care
2. reproductive division of labor
3. overlapping generations

(predominately hymenoptera and ispotera)

Kin Selection Theory
the more genes you share with someone else, the greater the fitness you gain by working together to promote survival of shared genes
What order is kin selection theory most applicable? why?
hymenoptera; because they are arrhenotokus-females from fertilized eggs and males from unfertilized
Characteristics of Eusocial Life
all social insects have castes that are differntiated functionally and morphologically (workers, soldiers, drones/kings, queens)

chemical communication is critical
trail, alarm, death pheromones

Termite participation
males and females both participate in colony activity
What pesticide is responsible for saving the most human lives?
Pesticide is broad term including what 4 things?
DDT was a modern miracle
inventor won novel prize
nontarget effects,
all domestic use stopped in 1972
Rachel Carson
“sea around us” marine books to promote pesticide regulation
responsible for ensuring that pesticides do not pose ‘unreasonable’ risks to human health or the environment
Detection Limits
just because you can measure it does not make it dangerous. The converse is also true. (1 or more pesticides were found 90% of the time in major streams)
No Observable Effect Limit
Exceeding Aquatic-life Benchmarks
what time of year are most pesticides used?
Endocrine Disruptors
hormones-chemical that control the body
What is happening to all kinds of amphibians?
Are pesticides a Cause for honey bee declination?
USDA says there is no one factor, other possible causes include water quality, diseases, mites, combinations
Pesticide ingredients are on ________.
the label
Signal Words
Danger-extremely dangerous, skin eye irritant
poison- small amt fatal
warning-larger amounts to injure humans
caution-least dangerous
your risk from pesticide depends on the pesticides’__________ and your___________.
toxicity and exposure
Use sites
sites indicated in the label (only use there)
Use rates
do not exceeding labeling rates or frequency is often illegal
Don’ts of pesticides
dont ignore directions
dont allow children access
dont put in food containers
Can enough food be produced organically?
will it be cheap enough for everyone to afford? (population will double in 30-40 years)
FDA estimated that __% of fruits and veggies have no detectable residues
Genetically Modified Organisms- genetic materials are added through means other than traditional plant breeding
How often do people eat them?
every day, nearly all soy, corn and cotton is GMO
NOP rules
95%-100% organic-USDA seal may appear
Why do farmers use pesticides?
Labor substitute
Instant results
Consumer demands
How do you keep plants healthy?
proper soil, moisture, sun, etc.
How can you find out what to do?
Cooperative Extension & learn about planting
How do you avoid pest problems?
be careful when you work (avoid wounding, don’t eat wet plants)
remove plant debris/diseased materials
preserve beneficials
How to help insects?
don’t kill them, use insecticides sparingly and be selective in which ones you use
What are they looking for?
prey, shelter, water, food (nectar, pollen)
Integrated Pest management
Monitoring (looking, traps) think about ecology (why, how) reduce need for pesticides
Common ‘organic’ pesticides
Spinosad- Bull’s eye (beetles, caterpillars, thrips, and flies)

Soaps/oils sprayed on insects

bacillus thuringiensis- caterpillars

B. israelensis- mosquito dunks

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