Cognitive Buffer Hypothesis

Cognitive Buffer Hypothesis

1. The main function of a large brain is to buffer individuals against environmental challenges by facilitating a behavioural response

   • Basically = provides flexibility in behaviour when facing changes in the environment =easier learning allowing species to overcome ecological challenges
     • buffer should favour increase survival rates, longer reproductive life compensating for the delayed reproduction associated with growing a large brain
       • large brains store, process and integrate more info about social and physical environment
         • increased liklihood that modification of behaviours or invent new ones in adaptive ways

2. Sol et al, 2005

   • relocated bird species from native range
     • establishment success higher for species with bigger brains relative to body size
       • so brain size is associated with establishment success
         • inferring species with bigger brains are able to invade novel locations better than conterparts
       • supports the hypothesis that large brain function may have evolved to deal with changes in the environment
         • enlarged brains enhance cognitive skills to respond to environmental change

3. Gonzalez-Lagos et al 2010

   • analsed data from 493 mammal species
     • larger brain = longer lifespan = new advantage
       • more oppertunities to adapt allows to live longer, more chances for reproduction = beneficial for species
         • compensation for longer embryonic development needed to generate larger brains
           • larger brains = longer to sexual maturirty = compensated for longer reproductive life
             • hyenas have larger brain than giraffes relative to body size = on av., live longer
               • CBH = larger encephalization = larger life span but equally possible long life favours large brains
                 • thus - possible longer life works on favour of delay of repro cycles allowing progenitors to invest more resources and time in offspring
                   • leads to formation of stable social groups whose members according to SIH deal with more cognitive demands than lone animals and goes hand in hand with large brains