Invertebrate Pheromones Flashcards
Define pheromones
Chemicals used for communication (within a species?)
‘pherein’ Greek = to carry or to transfer
‘hormon’ Greek = to excite
Provide a list of important names mentioned in class related to influential pheromone studies
Jean-Henri Fabre
Karl von Frisch
Adolph Butenandt
Karlson + Luscher
Who was Jean-Henri Fabre and what did he do?
an entomologist in the 1800-1900s who studied: PINE PROCESSIONARY MOTHS/CATERPILLARS
he observed that these caterpillars walk in procession and asked how they knew how to do that and where to go? thought chemicals and mechano-sensation must be involved
Who was Karl von Frisch and what did he do?
an ethologist who first studied EUROPEAN MINNOWS (and later bees)
he removed the fins of minnows and returned them to the tank and observed that other minnows would dart away
he determined that the injured fish released an ALARM pheromone when returned to warn the other fish - he called it ‘Schneckstopp’
What was the pheromone von Frisch first discovered? who was the sender, receiver, and what was the response?
he called it ‘Schneckstopp’ - an alarm pheromone
sender: injured minnow
receiver: other minnows
response: caused other minnows to scatter from the injured fish
Who was Adolph Butenandt? what did he do?
He won the Nobel Prize for chemistry in 1939 for isolating and determining the structure of the sex hormone and ATTRACTANT pheromone in SILKWORM MOTHS - it was the first real study on pheromone communication
called the pheromone: BOMBYKOL
he did a bioassay of the glands and separated out the components based on chemical properties and tested each fraction to determine which caused the attraction response in males
What is Bombykol? who is the sender, receiver, and what is the response?
the ATTRACTANT pheromone named by Butenandt
Sender: female silkworm moths
receiver: male silkworm moths
response: attraction
How do the male silkworm moths receive the female’s Bombykol pheromone?
they have high sensitivity in their hair antennae (with many sensilla pl.) which increases the surface area for increased reception
it causes the males to walk toward the females fluttering their wings (flight would cause the pheromone to move too quickly passed their antennae)
Define semiochemicals and give an example of one
“Semeion” = Greek for ‘sign’
chemicals that are used for communication or to elicit a response
ex. hormones that work within an individual
Define allelochemicals
chemicals that communicate between heterospecific organisms (different species)
Define hormones
chemicals to communicate within an individual
What did Karlson & Luscher do?
they coined the term ‘pheromone’ for communication within a species (intraspecific)
What are the major pheromone categories in invertebrates?
- alarm
- attractant
- aggregation
- hatching
- territory marking
- trail marking
What are the 6 general characteristics of pheromones?
- old
- ubiquitous
- organic molecules
- required in low concentration
- specificity
- diversity
What are the 5 functional (not universal) characteristics of pheromones?
- volatility
- stability
- persistence
- duality
- derived from existing chemicals
