Vallin et al., 2005 (peacock butterflies and blue tits) Flashcards
The peacock butterfly is a … … mimic when resting, but shifts to … defence when disturbed by performing a repeated sequence of movements exposing 4 major … on the … side of the wings accompanied by a … ….
cryptic leaf, active, eyespots, dorsal, hissing noise
This study tested the effects of these defence mechanisms by presenting butterflies to wild-caught blue tits and experimentally manipulating the butterflies in order to … the different elements of their defence strategy and see relatively how effective and important each element is.
isolate
The six kinds of experimentally manipulated living peacock butterflies were:
- Butterflies with eyes painted over and their controls (paint on another part of the dorsal side of their wing)
- Butterflies with their sound production aborted by removing a small part of their wing and their controls (removing an equally-sized area of the hindwing not used to produce hissing sound)
- Butterflies with eyespots painted over and sound production aborted and their controls
The results showed that … alone, or in combination with …, acted as an effective defence.
eyespots, sound
Only … out of 34 butterflies with intact eyespots was killed, whereas … out of 20 butterflies without eyespots were killed.
1, 13
The killed peacocks were …, indicating that they are not …. Hence, intimidation by bluffing can be an efficient means of defence for edible prey.
eaten, distasteful
Butterflies generally suffer from substantial … …, which has selected for effective …-… defence, especially in …-… species such as the peacock butterfly.
predation pressure, anti-predatory, long-lived
The hissing noise is produced by…
rubbing (structures on) the forewings and hindwing together
A … … prevented the butterflies from escaping by simply flying away
cold temperature
mimics cold spring or summer temperatures
Experiment carried out in …
Sweden
Blue tits raise their young on a pure … diet and therefore possess substantial …-… skills
insect, insect-catching
Before the trials began, mealworms were placed in a small plastic feeding tray at the far end of the log. This was to…
help the birds associate the low with food and encourage them to conduct a thorough search for food in this area of the room
Trials lasted … … (but were terminated earlier if the butterfly was captured and consumed)
30 minutes
Most butterflies … their bodies and … on the log to … the movement of the bird (after flicking their wings open), which may have been to increase the intimidating effect of the display
tilted, rotated, follow
There was no significant difference in … between…
survival, butterflies with or without the ability produce sound
- an no interaction between eyespots and sound could be detected
There was a significantly higher rate of survival in butterflies…
with eyespots compared to those without eyespots
Butterflies with covered eyespots showed more intense …-… behaviour. This appeared to positively correlate with the…
wing-flicking, length of time that blue tits spent within 10cm of the butterfly - may explain butterfly behaviour
The distance to the bird when the butterflies initiated wing-flicking was found to be greater…
at the second interaction between the two than at their first interaction (maybe because butterfly can no longer attempt to remain undetected - butterfly incorporates into its decision-making the possibility that it has not yet been detected)
The … are very effective in protecting the peacocks against … predation.
eyespots, passerine
The study found no indication that the combined effect of sound and eyespots is more effective compared to…
eyespots only
Another study suggested that the sound may have an intimidating effect on …
bats (as they reacted to the sound)
- it is possible that there are other butterfly predators or situations, yet to be investigated, where the combined effect is needed in order to protect the butterfly
Commas, which rely solely on crypsis as anti predator defence…
never shifts its behaviour to more active defence, no matter how closely the predator approaches
- the distance at which a butterfly starts to flick its wings when approached by a bird is associated with the butterfly’s type of antipredator device
This study was unable to find or reject a … effect of the peacock’s sound protection with the eyespot protection.
synergistic
- as eyespots were so effective (only 1 out of 34 attacked)