Communication Flashcards
What are some contexts for communication?
Alarm calls
Parent offspring interactions
Competition for mates
Courtship
What is an example of a benefit to a signaller and a cost to a receiver in communication?
Femme Fatale
Fireflies lure in males from other species and eats them
What is an example of a cost to a signaller and a benefit to a receiver in communication?
Female Ormia Flies
Receive and respond to the calls of crickets
What are some types of signals?
Vocal
Visual
Chemical/olfactory
Electric
Tactile
How did female hyenas form a pseudopenis?
In males, embryonic tissue forms a penis if exposed to androgens
Female spotted hyenas exposed to high levels of androgens in utero
So likely due to foetal exposure to male hormones
What do female foetuses exposed to testosterone develop?
Large clitoris
What is cumulative selection, what is an example of this?
Lots of small changes over time, rather than big evolutionary leaps
Female pseudopenis
What are the costs of a pseudopenis in hyenas?
Offspring born through clitoris
10-20% of females die while giving birth
What are the hypothesised benefits for a pseudopenis in hyenas?
High level of male sex hormone allowed killing of siblings and continued survival - evolved pseudopenis as a consequence
High level of male sex hormone made females larger
Also used to signal to other hyenas
Do ground or tree nesting bird species have a higher frequency begging calls?
Ground nesting
High frequency calls travel less far
What are the benefits of chick begging?
Is an honest signal of hunger
A signal that they are worth investing in
What is different about cuckoo chick begging calls?
The begging intensity of one cuckoo chick is similar to that of a whole brood of reed warblers and much greater than a single reed warbler
Means they have more feedings per hour
What are the main predators of Japanese Tits?
Snakes and crows
