biology zoology blog benno meyer rochow claws

Locked in, Locked up, Locked on…

Something that’s difficult to open

You can lock arms with someone, you can lock on to something or be locked in or even be locked up or locked out. But this essay is about animals that possess locking mechanisms. In the tropical waters of Ascension Island in the South Atlantic Ocean, for example, I once caught a pair of matchbox-sized trigger fish and observed their behaviour in my aquarium on board of the research vessel “Walter Herwig”. These denizens of the tropical seas as well as their cousins, the file fishes, can wedge themselves into rock cracks and coral crevices in such a way that it is virtually impossible to dislodge them by pulling at their tails. —>—>

biology zoology blog benno meyer rochow sand fish

Having a Helping Hand in Making Sand: Fish, Foraminifera, Worms and others

I had a brother in law who was an engineer, controlling and supervising the production of different types of glass, a material that is based on sand, lots of it. For that reason, he often had to make business trips to Yemen, a country that exports high-quality sand. Well, my brother always came back with a smile on his sunburnt face and full of praise for the sand’s quality and the locals’ hospitality and friendliness. But one day he returned with fever, feeling dizzy and weak: he had contracted yellow fever and had to spend several months in the isolation ward a hospital. I was wondering, isn’t there enough sand on our beaches? Couldn’t he have obtained his raw material for the glass production elsewhere without risking to get sick? —>—>