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The Triassic period started 252 million years ago after the Permian-Triassic extinction event, and in the 50 million years before the next extinction event, huge reptiles evolved and ruled the planet. One particularly fearsome species known as the rauisuchians stretched 9 metres from nose to tail with teeth like steak knives. However, the dinosaurs that existed at the time were much smaller creatures, many not much bigger than a cow. Though they were lacking in stature, some had some unusual features, like Tanystropheus, with a neck twice as long as its body.

We can maintain relationships with only around 150 friends

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Although the number of friends on your Facebook profile might be a long way north of 500, there is a natural upper limit to the number of people you can maintain a stable social relationship with. This is known as Dunbar’s number, and it plays out in many more situations than you might realise. For example, historically it was the average size of English villages, the ideal size for church parishes, and the size of the basic military unit, the company.


There is also a correlation between primate brain size and the size of their social groups. Extrapolate this relationship to the size of a human brain and guess where that leads us? Yes,  around 150 social contacts.

Mount Everest’s summit would be 2 kilometres underwater at the ocean’s deepest spot

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At its deepest point, in an area known as the Challenger Deep, the Mariana trench plunges to a depth of 10,984 metres (36,037 feet) below sea level. This is roughly the same distance below the waves that commercial airliners fly above them, and if Mount Everest were to start at the ocean’s lowest point, at 8849 metres it would still be more than 2000 metres below the surface.

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