Orphaned infant chimpanzees that received attentive, nurturing care from human surrogate mothers were found to be more intellectually advanced than the average human baby when both groups were compared at the age of nine months, according to a new study published in the latest issue of Developmental Psychobiology.When the chimps were nine months old, they took an IQ test normally used to evaluate human infant development. The chimps who had received responsive care aced the test, even surpassing the scores of average human infants tested at the same age.
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