It’s official: ICR “news” articles are now called Creation Science Updates. Or rather “Update” – they haven’t really mastered this pluralisation thing. The first article of this brave new era is called How Some Insects Can Eat Poisonous Plants, by Brian Thomas.
The chemicals used by milkweeds (including swan plants) and similar as a poison to deter herbivorous insects are known as cardenolides. They work by blocking the sodium pumps in cell membranes, but a handful of organisms are resistant to its effects. The most famous of these is the monarch butterfly, which was already known to have a amino-acid substitution mutation (referred to as “N122H”) in the gene coding for the pump that contributed to the butterfly’s immunity. A new paper in PNAS – Community-wide convergent evolution in insect adaptation to toxic cardenolides by substitutions in the Na,K-ATPase (pdf) – takes a look at the underlying genetics of all 18 insects known to be resistant, along with a number of their relatives. Continue reading