UiPath Platform: The Backend Engine Powering Your Automation - Session 1
Eating: Evolution and eating introduction A2
1. Evolutionary Explanations of
Food Preferences
Do we have an innate preference for certain foods?
How were these preferences adaptive in the EEA?
How do these preferences function now?
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2. Background
• The environment of Evolutionary Adaption (EEA) is
the environment in which a species first evolved
• Humans emerged 2 million years ago on the
African Savannah
• Natural selection favoured traits which allowed
survival in that environment
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3. Evolutionary Explanations of Food
Preferences
• Any current behaviours that appear to be
maladaptive (dysfunctional) can often be
explained as being functional in the past
• Our modern preference for calorific food
can be traced back to our ancestors where
it was adaptive
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4. • Early humans were frugivores and
relied on sweet fruits for their
survival
• Harris (1987) – babies like sweet
tastes
How are innate food preferences
adaptive: Sweet
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5. How are innate food preferences
adaptive: Salty
• In the hot African Savannah salty food
would have been needed to replace salts
lost through sweating
• Denton (1982) – animal research has
shown innate preference for salty food
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6. How are innate food preferences
adaptive: Umami
• Receding forests meant people had to
start eating meat
• Inclusion of meat acted as a
catalyst for brain growth
• Milton (2008) humans would never have
evolved to become active, intelligent
creatures without meat in their diet
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7. How are innate food preferences
adaptive: Sour
• Discouraged people from eating foods
that had gone off
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8. How are innate food preferences
adaptive: Bitter
• Discouraged people from eating
potentially poisonous food
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9. How are innate food preferences
adaptive: Fatty
• Needed in EEA as high levels of energy
needed to survive
• Burnham and Phelan (2000) preference for
fatty foods come from times of food scarcity
when this type of food is full of energy giving
calories
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10. How are innate food preferences
adaptive: Spicy
• Sherman and Hash (2001) – meat dishes
contain far more spices than vegetable
ones
• Spices have antimicrobial properties
• Could explain preferences
for spices in hot countries
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11. Food Neophobia
• Animals tend to avoid food they
have not come across before
• Frost (2006) As a food becomes
more familiar we show a greater
liking of it
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12. Taste Aversion Learning
• Developed as a means of survival
• If we eat food that makes us sick
it would be an advantage to avoid that
food in the future
• Garcia et al (1955) rats made ill through
radiation after eating saccharin developed
an aversion to it
• Explains why food poisoning leads to
inability to eat that food for a long time
(association)
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13. Innate food preferences in the modern
world
• Our food focus is no longer about eating enough
to avoid malnutrition as it was in the past
• Our preference for sweet food can now lead to
a highly calorific diet (chocolate, sugar)
• Our preference for salty food can now lead to a
highly fatty diet (crisps, chips)
•
•
•
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14. Evaluation
• Good explanation of food preferences
– i.e. good explanation of why we like foods
which have very little goodness
• Focus on ultimate rather than proximate
causes
– i.e. evolutionary approach considers
ultimate causes rather than looking at
maladaptiveness (overeating)
– Genome Lag
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15. Evaluation
• Research
– Difficult to falsify
– However, we can study related species who face
similar adaptive problems to our ancestors
– Fossils show the evolution of meat eating
• Suggests evolution has stopped though Wills
(1999) say this is not the case
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16. IDA
• Reductionist
• Determinist
• Cultural Differences
– Infant preferences of sweet food is universal
– However, after infancy there is a broad range of likes
and dislikes
– Evolved factors are modified by experiences made
available by our culture
• Supports Nature-Nurture debate
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