Remember all those times you were told size doesn’t matter? They lied.

No lies about size, though, when it comes to gorillas beating their chest. It turns out that those percussive sounds of gorillas drumming against their upper chest reveal accurate information about their size. The bigger the gorilla the lower the frequency of the sounds, possibly because bigger gorillas have larger air sacs near their larynx. This means that chest-beating isn’t just a visual display, but what a study calls an “honest signal of competitive ability.” And wouldn’t you know it, the bigger males attract the females, after all.

Gorillas stand up and thump their chests with cupped hands, not fists, which allows for a sound that can be heard up to half a mile way, signaling to females from other troops where the best mating choices lie. Not only that, it also informs other males if and when to choose to get into dominance fights – thus actually preventing aggression, since it makes smaller gorillas think twice. Or whatever the equivalence is in gorilla decision making….

They don’t thump all day; and apparently each one has a signature rhythm that allows them to be identified.And they are not the only ones. Honest acoustic cues to size can be found in the bellows of alligators and the vocalizations of North American Bisons, to name just a few, with those who have longer vocal tracts mating more successfully.

And if you don’t have a voice? No problem! Funnel-web building spiders, for example, use their body weight directly. It determines their web vibrations, so that conspecific receivers can reliably predict a potential opponent’s competitive abilities. Get that net swinging!

And then there are the Indian jumping ants. They are the first species that we know of that can voluntarily shrink their brains up to 25% – all in the service of their ovaries that swell up to five times their earlier size when energy used for the brain is rerouted. They do this when a queen dies, eliciting competition between these emerging pseudo-queens, one of whom takes the prize with the biggest reproductive system. Normally colonies die off when their queen goes. This system makes these specific colonies functionally immortal.

Not only that. If they didn’t make the cut, they can regrow their brains and revert to the previous existence as a worker ant. Oh, as a dear reader recently declared about nature’s tricks: ASTOUNDING!

Now all we need to learn is how to prevent our own involuntary shrinking of brains by any degree…

Here is traditional Rwandan music to end the week. Enjoy the sunshine!

Photographs are of things that are small and beautiful and blissfully silent.