The world’s population is continuing to grow; we could have as many as 11.2 billion people by 2100 ( https://en.wikipedia.org/wiki/Projections_of_population_growth ).  If that projection comes true, how will we feed everyone?

One solution may be to eat insects.  That’s not as far-fetched as it sounds.  This is what early mammals ate, and this ability has been carried forward to us.  According to a new genome analysis of 107 mammal species, published May 16, 2018, in the journal Science Advances, we have inherited a gene for a special enzyme that would allow us to digest these six-legged bugs.

Study author Christopher Emerling  at University of California, Berkeley, said:

One of the coolest things is, if you look at humans, at Fido your dog, Whiskers your cat, your horse, your cow; pick any animal, generally speaking, they have remnants in their genomes of a time when mammals were small, probably insectivorous and running around when dinosaurs were still roaming Earth.

It is a signature in your genome that says, once upon a time you were not the dominant group of organisms on Earth. By looking at our genomes, we are looking at this ancestral past and a lifestyle that we don’t even live with anymore.

The researchers in this study looked at genes for enzymes called chitinases, which break down insects’ hard, outer shells.  Their target group was mammals that have placentas.  This is the largest group, and allows for longer development in the womb.  They found five different chitinase enzyme genes.  Not surprisingly, the greater the percentage of insects in an animal’s diet, the more genes for chitinase were found.  Humans have one functioning chitinase gene; some people today do include insects in their diets.  But we actually have remnants of three other chitinase genes in our genome, though none of them function.

So just perhaps, eating insects could be the salvation of our species.

The complete article, “What we inherited from bug-eating mammal ancestors” by Eleanor Imster, can be found at  http://earthsky.org/earth/insect-eating-human-ancestor-genes? .  The photo came from that article.