Jellyfish are a highly diverse group of aquatic animals. Their diameters range from 1 mm to over 1 m. Most have long tentacles, in some cases reaching more than 10 m in length. They come in a wide array of shapes and sizes. Some are bioluminescent; others are …
Holidaymakers concerned about fresh volcanic eruptions causing flight-disrupting ash clouds across Northern Europe might be reassured by a study setting out the first reliable estimates of their frequency.