Avian intelligence and social cognition Flashcards
Definition: intelligence
–ability to acquire & apply knowledge and skills (OED).
–the ability to adapt to new conditions and to successfully cope with life situations.
–a collection of mental capabilities involving the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly and learn from experience.
-considering past, present and future to solve complex problems
Definition: social cognition
–Understanding & predicting the behaviour of conspecifics (other members of their social group)
( see: Individualised societies, de Waal & Tyak 2003)
–stable groups, long-lived members
–members recognise each other as individuals,
–on-going relationships,
-various social statuses within the group
–learned survival skills & social behaviours.
e.g. in primates, elephants (matriarchal memory), meerkats (learning+teaching), hyenas (matriarchal organisation), wolves (alpha male and female pack leaders)
^all these examples are mammalian – so what about birds?
why are intelligent birds interesting?
*Not mammals
*Theories of intelligence/social cognition in mammals has focused on evolution of mammalian brain esp. Neocortex (particularly in social species) and this neocortex is absent in birds
Birds have different brain architecture
It was thought that bird brain lacked pallial tissue required for memory and social recognition
We now know that there is a lot of pallial tissue present but it is distributed differently in comparison to mammalian brains
(see diagrams in notes)
Birds have different life history constraints compared to mammals
Different constraints on avian brain size
–weight, size for flight
Very different modes of information processing,
eg. preferential use of different eyes for different tasks
As seen in chicken chicks:
–left eye for physical (avian predators),
–right eye for social (imprinting reinforcement)
Candidates for ‘intelligent’ birds
Folklore: eminence of crows (especially ravens) in lore of northern peoples.
Basic natural history observations
Taxonomic groups:
– Order Passeriformes
*Family Corvidae (crows, jays, magpies)
*Family Sturnus (starlings)
–Order Psittaciformes (parrots)
Potential reasons for high intelligence:
*Live in complex environments
*Live in groups with complex, long-lasting social bonds
*Long-lived,
*Complex vocal & behavioural repertoire
*Including vocal mimicry. This demonstrates learning capacity as an adult
e.g. Lyre bird song repertoire used in courtship
Scientific approach for measuring intelligence in mammals
compares total brain volume to body volume
Or perhaps more accurately, ratio of neocortex
*Relative brain volume bigger in ‘intelligent’ mammals
*Neocortex : brainstem ratio higher in ‘intelligent’ mammals
Relative brain volume & forebrain size in birds follows same pattern:
*much higher ratio in corvids
(see diagrams by Emery & Clayton Chl in Rogers & Kaplin)(2004)
Why study corvids and not parrots?
*Focus on corvids because parrots are understudied in wild
(difficult environments: e.g. tree tops in remote tropical forests).
Review of Corvid intelligence by Emery & Clayton, Science 2004
*Corvids are easier to follow (more open environment, near/in urban ares) and easier to breed in captivity
Tool use and manufacture
Does this reflect understanding?
tool use example: new caledonian crow Betty solving a problem
New Caledonian Crow (Corvus moneduloides) tool manufacture behaviour:
–Hook tools from twigs
–Step cut Pandanus leaves:
*standard pattern
*Carried around
*Innovation? (e.g. increasing number of steps)
Modifying tools:
Caledonian crows modify their tools over time in a non-random way to improve function e.g. by adding steps to a leaf tool or whittling down a stick that is too thick
Evidence of reasoning in corvids?
see: http://users.ox.ac.uk/~kgroup/index.html
Corvids use traffic to break open tough nuts, collecting the crushed nuts is then difficult, so they use pedestrian crossings, wait for the lights to change and collect the cracked nut in safety
Corvid ‘mental travels’ in space and time
*episodic memory: ability to travel mentally in time in order to re-experience memories of specific past episodes
*future planning: ability to plan for future needs
*Previously thought to be an ability unique to humans - the so-called mental time-travel hypothesis (Suddendorf & Corballis 1997)
example of mental travels: Clarkes & European nutcrackers
–cache their food, one individual can store upto 30,000 pine seeds in the autumn over a wide area
–Recover up to 6 months later, with much more success than simply ‘re-foraging’
example of mental travels:
Western scrub jay (Aphelocoma californica)
Cache variety of foods of differing perishability
(experiments reviewed in Emery & Clayton, 2004)
*remember where items cached, & what cached & when
*Can distinguish between same food type stored at different time, and will not recover old items (that are too old to be good to eat).
*suggests episodic-like memory: what, where & when.
Social cognition of cache protection and pilfering amongst blue scrub jays
Caches susceptible to pilfering, so social context of caching important:
Birds appear to consider “Did anyone see me hide the stash?”
Cache protection strategies amongst blue scrub jays
–Hiding food behind barriers between potential pilferer (pp) and cache
–Waiting till pp distracted
–Leading pp away
–Making false caches
–If observed, return later, alone, & re-cache food.
is this behaviour based on understanding & simulation of another’s viewpoint, or simply reacting to presence of conspecific by re-caching?
Further experiment with blue scrub jay :
- Allowed to cache in private or observed by conspecific, then recover caches in private
- Experienced pilferers were more likely to re-cache – when observed caching
- Inference is that those birds who had been thieves in the past engage in ‘experience projection’.
–Is this mental attribution? Food for thought
More evidence for mental attribution: Corvids e.g. Ravens
*Ravens (Corvus corax) discriminate between knowledgeable and ignorant competitors
“who saw me hide the stash?”
*Gaze following in ravens
*able to interpret if a gaze is meaningful – only seen in some birds and mammals
