Pests, Plagues & Politics Lecture 13 Insect Communication: Light and Sound Shows

Key Points: Insect Communication: Light and Sound Shows Bioluminescence – Which orders use it? – How do they use it? Sound Communication – Which order is best known for “singing” – Functions of acoustic behavior – Mechanisms for sound production – Temporal separation

Communication with LIGHT Fireflies & Glow-worms Misnomer – neither Fire, nor are they Flies (well, sometimes they are) Coleoptera (Beetles) – families Lampyridae Phengodidae Utilize bioluminescence for sexual communication.

Communication with LIGHT Bioluminescence – Nearly 100% of a firefy’s light is given off as light – Compare this to an incandescent light bulb, which gives off 10% light and 90% heat The chemical reaction: – Understanding this chemistry led to the making of glowsticks!

Fireflies Wonderful scientific names such as: – Photuris “tail light” (photos = light - ouron = tail) – Photinus “a little tail light” (diminutive form)

Fireflies Courtship Signals – Flash patterns are species specific – Normally females (on the ground) signaling for flying males. – Females frequently wingless or even “larviform” as adults. Female Photinus bromleyi The Mating Game

Fireflies Synchronous-Aggregate Synchronous-AggregateFlashers – S.E. Asia

Glow-Worms Some are beetles - some are flies – ergo, the confusion of common names.

Glow-Worm (a fly) Glow-Worm (a fly) Arachnocampa luminosa - A fungus gnat from New Zealand

Glow-Worms Larvae create sticky mucous strings and light them up with their glowing tails to lure and trap other insects!

Glow-worm (a beetle) Phengodes sp. larva, Maryland

Frequently asked question Why are there no fireflies in Oregon?? ARE ANSWER: There ARE fireflies in Oregon! Zarhipis integripennisPterotus obscuripennis

Oregon Glow-worms Two beetle species in two different families Two beetle species in two different families – Zarhipis integripennis (Phengodidae) a predator of millipedes light from each body segment – Pterotus obscuripennis (Lampyridae) a predator of snails light from terminal body segment – Bioluminescence from embryo-larva- larviform adult females (males do not “glow”)

Communication with Sound “ A great many insect species produce sound by means of special structures, but only a few, such as crickets, grasshoppers & cicadas, are heard by most people” – Borror & DeLong The ORTHOPTERA – others: Coleoptera, Hymenoptera, Isoptera, Homoptera & Lepidoptera

Functions of Acoustic Behavior REPRODUCTION – primarily for mate attraction &/or territorial display (much like birds) REPELLENCY – Passalid beetles; hissing cockroach, et alia DEFENSE ALARMS – termites, et alia

Functions of Acoustic Behavior FOOD GATHERING – Phonotaxis by parasitoids & predators – Female flies of the genus Ormia must find a specific cricket host on which to deposit their parasitic maggots. To reproduce, female flies must perform the same task as female crickets - to find a singing male cricket. – has led to the “ development ” of smart, silent, satellite male crickets.

Mechanisms for sound production STRIDULATION – the rubbing of one body part against another grasshoppers, beetles, ad infinitum THE most common insect musical “ instrument ” VIBRATION – of special membranes known as TYMBALS cicadas, some leafhoppers, some moths – of wings or thorax. incidental sounds from many, many species.

Chirp Chirp! Only the males chirp – There are special songs for courtship, fighting and sounding an alarm Sense sound using tympani (hearing organs) in their front legs Want to know the temp.? – Chirps/15 sec

Mechanisms for sound production STRIKING against a substrate – alarm calls of damp wood termites EJECTION of air – death head moth, hissing cockroach

The most noted “ singers ” The Orthopterans – grasshoppers - crickets - katydids – Stridulation is the primary mechanism – Two Song Types “ Calling ” songs by males for females “ Fighting ” songs by males for territorial defense

Temporal Song Separation Night Singers – nearly all katydids Day Singers – most grasshoppers Day &/or Night Singers – most crickets

Chorus Singers Cone-headed grasshoppers & tree crickets – More than two individuals singing simultaneously, with their sound pulses synchronized or alternating.

Cone headed grasshopper Neoconocephalus retusus

Tropical House Cricket Gryllodes sigillatis

Southern Wood Cricket Gryllus fultoni

Pine Tree Cricket Oecanthus pini

Two spotted tree cricket Neoxabea bipunctata

Hubbell ’ s Ground Cricket Pictonemobius hubbelli

Tidewater meadow cricket Conocephalus nigropleuroides

Slender Meadow Katydid Conocephalus fasciatus

Long-spurred Meadow Katydid Orchelimum silvaticum

Common Meadow Katydid Orchelimum vulgare

Palmetto Conehead Belocephalus sabalis

Key Points: Insect Communication: Light and Sound Shows Bioluminescence – Which orders use it? – How do they use it? Sound Communication – Which order is best known for “singing” – Functions of acoustic behavior – Mechanisms for sound production – Temporal separation

Cicadas en masse, Princeton, 2004