Move over, Charles Darwin. According to National University of Ireland pioneering biologist Kevin Kavanagh, because an insect’s immune system - specifically its haematocytes - closely resembles one part of the mammalian immune system - or its neutrophils - using moths, caterpillars or Drosophila (fruit flies) instead of mice and rats just seemed like the next step - and a more humane one - in the evolution of drug research and testing.