1. A Bug’s Life

2. Entomology Study of insects Most successful and preponderant taxon
Most diverse of taxon
Specially beetles: weevils
Ants have largest biomass on globe

3. Arthropods Phylum Arthropoda = jointed feet
Insects, spiders, scorpions, sun spiders, ticks, mites, trilobites
Sea spiders, crabs, shrimp, lobsters, amphipods, isopods, millipedes, centipedes

4. Arthropods

5. Characteristics Exoskeleton Open circulatory system
Chitin
Open circulatory system
Heart, ostia, dorsal blood vessel
Double ganglionated ventral nerve cord

6. Insects Beetles Flies Moths, butterflies Fleas Lice Thrips Springtails
Silverfish, firebrats
Mayflies
Dragonflies, damselflies
Earwigs
Crickets, hoppers, katydids
Roaches
True bugs
Bed bugs
Beetles
Dung, carrion, etc.
Flies
Moths, butterflies
Fleas
Lice
Thrips

7. Relation to ecology
How do insects communicate?
CHEMICALS

8. Chemicals 2 types Pheromones: same species
Releasers: elicit immediate response
Primers: modify physiological state
Caste designation in termites
Allomones: different species

9. Scheme Scheme similar to symbioses Sender/receiver +/+ → synomones
+/- → allomones
-/+ → kairomones
-/- → antimones

10. Synomones (+/+) : Allomones
Flower odors
Sweet smell
Foul smell

11. Synomones (+/+) : Pheromones
Sex
Practically every insect
Aggregation
Aposematics
Anti-aggregation
Bark beetles
Trail
ants
Alarm
Ants
Aphids
Social wasps, bees

12. Defense Allomones (+/-)
TONS of arthropods
Released from glands
Hymenopterans
Roaches
Dung beetles
Aquatic insects
True bugs
Cosmopepla bimaculata
Triatoma spp.

13. Defense Allomones (+/-)
Stick insects of North Am.
Bombardier beetle
Termites
Caterpillars
osmeteria
Vinegaroon
Millipedes
Anti-aphrodisiac pheromone
Gnats, mussies
Anti-oviposition pheromone
Leave “scent” → don’t oviposit
Egg mimic on plants

14. Defense Allomones (+/-)
Sequestration
Caterpillars, moths, butterflies
True bugs
Beetles
Reflex-bleeding
Spanish fly

16. Allomones : Kairomones (-/+)
Release of aphid alarm pheromone
Human sweat → female mussies
Leaf “scent” → oviposition/feeding
Tritrophic Level Interactions
Caterpillar → Leaf→ Parasitoid wasp
Sound cues!
Crickets chirp → Parasitoid flies