McGill researchers attempt to control organism size, double the size of ants

A team of scientists at McGill’s evolutionary and developmental biology lab have doubled the size of experimental ants, achieving a huge step in defining the role of genetics and the environment on the size of an organism. The researchers, led by Dr. Ehab Abouheif, published a paper in Nature Communications detailing their findings. These findings are huge in the discipline of epigenetics, the study of why and how genetically identical organisms might still display different traits.

Their research allowed them to zero in on a single gene, EGFR (epidermal growth factor receptor), that can be methylated, a chemical process where a methyl group is added into a compound in place of a hydrogen atom. The methyl ‘coating’ ended up accounting for 70% of ant size differences, depending on the degree of methylation. This is also slightly different from genetic modification, as the genome of the organisms is not altered, removed, or replaced.

Previously thought to be a highly complex task dependent on a mixture of many different genes and environmental factors, size manipulation turned out to be relatively easier than expected. In fact, the scientists were able to grow ants that fell along a continuum of sizes, ranging from 1.6 millimetres long (‘minors’) to 2.5 mm (‘majors’), nearly double the size of your average run-of-the-mill ant. The methylation of the gene can be influenced by many factors, including the types of food consumed, showing the environmental effects on size.

With these findings, further research can be conducted for other traits, and even potentially human applications. Major and minor type ants differ in more than just size – they also tend to adopt different roles in the colonies. The gene could therefore have an effect on behaviour, which is the subject of future tests. It’s also possible to extend the work to find links to other traits, such as weight, strength, skin colour, and intelligence. A further connection to food could have applications on human health and wellness.

Maybe not as impressive as Ant-Man, but possibly more realistic.