The Evolution of Communication Flashcards
Sensory Exploitation Hypothesis
The evolution of signals that happen to
activate an already-established sensory
system of signal receivers in ways that elicit
responses favorable to the signal sender.
* New forms of communication are created from preexisting ones.
Honest Signal
If a mimic could easily display threats that do not accurately
display their abilities, then natural selection would favor
receivers that ignored the fake signal
* Reduces the value of producing them
* This would favor honest signals that could not be devalued
by deceitful signalers
Deception
Net Benefit Theory
maladaptive response caused by
the sensory mechanism that results in loss of fitness for some individuals under some circumstances but overall results in a gain for most individuals
- overall the mechanism is beneficial for the species
-ex, still respond to mating signal even if possibility of illegitimate signaler
*Illegitimate signaler/receiver
reciever: - predators take advantage of
signals that are provided by their prey
signaler: It is utilizing a generally advantageous signal
Hypothesis vs Prediction in Ethology
Animal Behaviorists use natural selection
to help them construct hypothesis about why a behavior proliferates and then create predictions about how an animal will act if the hypothesis were true
IntRAspecific communication
between same species
IntERspecific communication
between different species
Bats and Whistling Moths
communication arms race:
Bats hunt for moths in the dark using ultrasonic sound via echolocation.
* Moths have come up with ways to hear those sounds and take evasive action when a bat is closing in. or even respond “don’t eat me I taste bad”
Male and female moths can hear ultrasonic sounds from male moths.
Spermataphore
protein capsule made by male containing nutrients, fluids, and sperm. insects, arthropods, mollusks, salamanders, cephalopods, and mites use this.
Provide 2 examples of sensory exploitation
- Cichlid fish: Males use dummy eggs because of a preference for egg spots due to pre-existing bias is for carotenoid-rich– food like shrimps, algae, and, notably, fish eggs indicative
of foraging skills - evolution of a courtship signal in the
water mite: The male’s behavior and its hereditary basis spread because
it effectively activates a preexisting prey-detection mechanism in females
Novel Artificial Signals
Novel experiments can be designed that trigger responses from animals never encountered the stimuli before
Rxn: In all cases, artificial attributes elicited stronger reactions than natural ornaments
(frog sounds, yellow pieces added to platy fish, added feathers to auklets)
why? Maybe due to ancestors, ex spiny lizards painted blue.
Panda Principles
They have a small extra finger for stripping bamboo. The principle of imperfection where things don’t have to be perfect to
exist, they just have to be good enough to maintain the niche
Parthenogenesis
Asexual females reproduce. Ex. Whiptail lizards. And they still display courtship despite not needing to.
Hyenas give 2 hypotheses for pseudo penis using the adaptionist approach
They display to each other as a greeting, and it has drawbacks in childbirth. We don’t know exactly how it happens, it’s not entirely testosterone-related.
Explore Hypothesis:
Aggression: Maybe the hormones that produce a pseudo-penis also facilitate neonatal aggression
Communication: they communicate thru anal glands so maybe a pseudo-penis makes communication easier among both males and females.
Submission: Pseudo-penis helps to maintain social order.
Social- Bonding: After conflict some
individuals initiate a greeting ceremony to reconcile their differences with previous opponents
Control Over Reproduction: No forced copulation
European Toad
Honest signal threat display. Croaks when touched by a male trying to steal mate.
Honest Signal: Give 3 examples
- Barking Gecko
- Collard Lizard, mouth opening
firefly femme fatale
Illegitimate signaler
Novel environmental theory
the current environment is so
different from that in which the behavior evolved that
there is insufficient time for an advantageous mutation
- no time to fix the problem
elbow orchid
Tricks wasps with sexual deception to get pollinated. Illegitamite signaler.
Crickets no longer chirp in Kaui
due to a parasitoid fly. Illegitimate receiver
Communication
n is defined as the transfer of information
between two or more organisms
*Signaler and receiver
