MARB 403 Lab 9
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Intelligence and Cognition
by Bernd Würsig
Are dolphins smart?
- Intellience: the mental capabilities of a human or non-human species by solving problems
- Cognition: pre-planning before you do something, using past experiences to shape behavior
Measuring dolphin intelligence is harder
- Can't use manipulative skills
- Can't compare different species
- There is another way: The absolute method
The Absolute Method
Attempt to find out how an animal thinks about things
Thinking: mental manipulation of the internal representation of the external world
- Communication is best window into an animal's mind
- Complex communication = more intelligence ?
Is bigger brain always better? Not necessarily.
Brain is responsible for
- motor, bodily functions, and sensory reception
- more stuff to control (i.e. bigger body) positively influences brain size
Encephalization Quotient
Ratio of brain mass observed to the brain mass predicted from an allometric equation of brain-mass-to-body-mass ratio of mammals as a whole
- 1 = average
- Sperm whales have 0.02% EQ
- Bottlenose dolphins' brains are 1% body mass
- Rival that of humans and great apes
Dolphins and pinnipeds can do a lot of tricks, but this is operant conditioning of what they do in the wild.
Sign language
- Dolphins understand grammar (rebutted?)
- deuterolearning / meta-thinking / creativity
Behavioral Complexity in Nature
Very social Sophisticated ways of communication
Baleen whales
- very vocal
- not as social (only when mating)
- some aggressive (humpback) or passive (right)
Cooperation in feeding for some
- echelon
- bubble-netting
Toothed Whales
Highly social except for few exceptions
Dolphin vs. Dolphin intelligence
- Hector and Harbor porpoise (small groups with close communication)
- Pantropical spotted and striped (large herds with fewer individual signature whistles, aware of each other, strategy in male alliances)
Matriarchal Lines (Culture)
- Sperm whales, pilot whales (long care from mothers)
- Resident Killer whales (socially "closed" pods, dialects, mate outside pod but don't leave, transient orcas beach themselves for hunting)
- Bottlenose dolphins (signature whistles, Galveston dolphins learned to feed from nets without getting caught)
Play
- All young animals play
- Only a few adults play (survival or pure enjoyment
- [VIDEO] Hawaiian bottlenose dolphins sliding down humpbak whale rostrum
"Smart" is a relative term: all mentioned animals share knowledge in order to survive
Cetaceans have Complex Brains for Complex Cognition
Lori Marino, et al.
Cetacean brain evolution:
- Social forces
- Complex society (communication, collaboration, competition)
- Self-recognition, recognition of other individuals
- Complex echolocation
Manger's rebuttal:
- Oceans cooled, requiring more heat-producing cells
- no evidence of complex cognition ?
Cetaceans evolved from artiodactyls about 55 MYA Brain size increased, body size (for most odontocetes) decreased
Initial brain hypothesis: Neocortex once thought very primitive
- Actually has regional parcellation comparable to that of terrestrial mammals
Cognitive functions associated with same regions as in primates
- Same parts, just rearranged in different locations
- Supported by spindle cells (convergent with primates!)
3 types of glial types:
- Oligodendrocytes
- Astrocytes
- ???
More glial cells could actually mean a more complex brain!
Cognition and Behavior in Lab
- declarative
- understanding symbolic representation
- procedural
- how things wor kand how to manipulate them
- social
- interacting with others
- self
- knowing own image, body parts, etc
Cognition
- Dolphins can learn associations
- Mimicry
- Only other mammal that can do vocal mimicry
- understand significance of human pointing gestures and head gazes
- Metacognition: knowing what you know
- Mirror test: aware of own behavior
Cognition and Behavior in Wild
- Live in large, complex groups
- Cultural learning of dialects, foraging sites & strategies
- known in bottlenose dolphins, humpback whales, killer whales, and sperm whales
- Social complexity and culture depend on complex communication system
Dolphins produce several types of sounds
- sequential order of whistle production is important feature important part
Conclusion
Lots of evidence that cetacean brains underwent elaborate reorganization and evolution in response to intelligence and cognition (not cooling)
Resulted in Expansion of neocortex
Exhibit some of most sophisticated cognitive abilites