Horned ghost crab, Grand Anse, Praslin Island, Seychelles

Fight for your lefts

It's International Left-Handers Day, so why are we showing this horned ghost crab whose right claw is noticeably larger than its left? Well, while its beefy right pincher is useful for grappling with other crabs, the horned ghost crab uses its left claw for precision work like bringing food to its mouth, as a human southpaw does. (Admittedly, there is no evidence to suggest they use it for writing or playing golf.)

Among humans, lefties are outnumbered 9 to 1 - so simple actions, from typing on keyboards to swiping on dating apps to zipping up a jacket or reaching for the toilet paper, are by design just a little harder for lefties. International Left-Handers Day is observed on 13 August to highlight this imbalance and work toward lefty-inclusive solutions. Call it a lefty rights movement.

If you're a righty, try going through today as if your left hand were dominant - you'll find it's not just lack of practice getting in your way but human design too. And once you've thrown both hands up in frustration, give 10% of your fellow humans a big hand for their everyday resourcefulness.