Why are there so few insects in the sea? © iStock

Why are there so few insects in the sea?

There are various theories as to why there aren't many insects in the sea - from an abundance of predators to lack of flowers.

Asked by: Steve Dawes, Birmingham


By the time insects evolved, the sea was already full of fish and predators. Insects’ respiratory systems rely on having air inside all the time, so they can’t dive deep enough to avoid being eaten. Another theory is that their survival depends on flowering plants. And as there are no flowering plants in the sea, there are no insects.


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