#15: The Success of Insects

Litinsects #15: The Success of Insects

The first insects evolved around 410 million years ago. They have witnessed many global changes and numerous catastrophes that wiped out plenty of other species yet somehow they survived and continue to thrive. With around 1 million named species, insects currently account for around 2/3 of animals worldwide and are found in almost every kind of ecosystem. So what makes insects so successful? Here‘s what it comes down to:

1) An insect’s EXOSKELETON provides protection, support, and prevents desiccation (water loss)

2) Their SMALL SIZE means they can hide easily from predators, they require fewer resources to survive, and they can disperse easily (by themselves or by being carried)

3) FAST GENERATION TIMES means that insects potentially evolve faster due to the accumulation of more mutations per unit of time. This means, insects have many more chances for new species to arise than say an animal that needs years or decades to reproduce, meaning they are well able to adapt to environmental changes

4) METAMORPHOSIS is a huge advantage that has allowed for a separation of lifestyles among different phases of life. To give a very basic example of this: a caterpillar eats very different food than a butterfly, meaning that parents don’t need to compete with their children for food! Pretty handy if you ask me...

5) Many groups have developed defenses to avoid predation. Some species use CAMOUFLAGE to hide in plain sight while others store or produce CHEMICALS or develop MECHANICAL DEFENSES to avoid being eaten

6) And finally, the evolution of FLIGHT has majorly benefitted insects, mainly for the ability to disperse (to find mates, to search for food, to avoid predators, to find a new home when resources are low). Other uses for wings include protection, heat retention, camouflage, visual communication, or courtship displays

Of course these are generalized factors and not every group will utilize every one... But in general these factors have immensely contributed to the success of insects all over the globe.

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