1. At least seven species of dolphins have been sighted in British waters - the easiest the spot include bottlenose and common dolphins.
2. Studies show that dolphins can see in shades of grey, as well as the blue-green spectrum.
3. Pink river dolphins live in the Bolivian Amazon.
4. Dolphins usually stay in shallow water but are capable of diving down to depths of 260 metres.
5. The dolphin is the only mammal that gives birth to its baby tail first.
6. Each dolphin's dorsal fin is totally unique.
7. A group of dolphins is known as a pod.
8. Bottlenose dolphins have bigger brains than humans (1600 grams versus 1300 grams), and a brain-to-body-weight ratio greater than great apes.
9. Dolphins can communicate with various noises, usually in the form of clicks and whistles.
10. Endangered dolphins like the Maui’s dolphin are on the brink of extinction due to entanglement in fishing gear. All dolphins are threatened by pollution, climate change, and commercial harvest.
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