At this time of year in Europe, you may have noticed something in the air. Dust-laden winds blowing from the Sahara desert cause “seasonal haze episodes” that can even result in mud rain.

People often think of substances like arsenic or cyanide when asked to name a poison. However those are not the most toxic substances. So what are the actual deadliest poisons on earth?

As night closes in across Kentucky a small chubby spider makes a silk line between two plants. She then moves along her “trapeze wire” and waits. After a while a moth approaches within range, and the spider unleashes a swinging sticky ball, ensnaring the moth and pulling him in to be eaten. The attacker is a bolas spider, and she hunts by releasing an odour that precisely matches the chemical composition of female moth mating pheromones. The male moth is lured in, but instead of getting a mate, he gets eaten.

Imagine dolphins disappearing from the world’s oceans as a result of prolonged climate change and slower evolution. As shocking and unlikely as such an event might be, it happened in the past to a group of marine animals: the ichthyosaurs.