Fact: We can only really do two things: contract a muscle or secrete a liquid.
You might think of yourself as a walking, talking marvel of nature but when you break it down humans – just like all animals – are very limited in the ways we can interact with our environment.
Take any activity you can think of and see if it fits into one of these two categories. Muscle contraction is our method of physical movement, but it goes well beyond just fight-or-flight: speech, breathing and our circulation are all entirely driven by muscular contractions. Meanwhile secreting liquids is one of our favourite hobbies: from digestion to reproduction we spend a huge amount of our time producing various secretions of various compositions for various purposes.
It is strange to think that our complex biology boils down to just these two mechanisms of influencing the world around us – but then again, plants are restricted to just secreting liquids and they have dominated the planet for millions of years.
Credit to Jacob Lam – this one is his favourite science gem.
‘Another one of Mr Shaunak’s Little Bites of Science’
Image under Creative Commons license