How many insects have been discovered so far?

The total number of named species is around a million.

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But it's very hard to tell how many species have been counted twice. The differences between some species can be a matter of an extra antenna segment here or longer bristles on an abdomen there. Not only is it easy to make mistakes, it's also difficult to verify old records without going back into the field and reexamining living specimens. This isn't important enough to justify the amount of effort it would require from entomologists. The total number of undiscovered insect species is an even bigger guess. Scientists make extrapolations based on the rate at which new species are reported each year or the number of new species found per hectare of rainforest. Estimates of this total vary from 2 million to 30 million, meaning we have discovered between 3 and 50 per cent of insect species.

WHY DID WE START MEASURING TIME IN SECONDS, MINUTES AND HOURS?

We inherited the tradition of measuring time in units of 12 from the Babylonians, whose numerical system used a base of 60. There are roughly 12 lunar cycles in a year, which may explain why we divide years and days into 12.

WHEN DID PEOPLE START PUTTING SHOELACES ON THEIR SHOES?