Human and Macaque Breast Milk Compared (IMAGE) University of California - Davis Caption Human breast milk contains extra nutritional elements compared to that of rhesus macaque monkeys, UC Davis and Harvard researchers find. This may be because human infants have further to go in development after birth than our close relatives. Credit California National Primate Research Center Usage Restrictions May be used with acknowledgement. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.