so I'd be pretty interested if you could share with us some of the major ways insects have shaped the evolution of the non-marine biosphere, based on Shaw's work.
I will have to read further to properly answer based on Shaw's work, but insects were diversifying and munching on plants and their reproductive parts, spores and seeds for many millions of years before vertebrates showed up on land. They were a major selective influence on plants and had shaped the terrestrial environment that vertebrates colonized. They fed on and were in turn fed on by the newcomers.
I think most people are unaware of the implications of species diversity and population densities of insects today but also for the past ~400 million years. There are now around 2 million identified species of insects and conservative estimates are that there are at least 10 million species. That means that we know almost nothing about 80% of insect species. More than half the biomass on the planet is estimated to be insects. Insects eat a large percentage of the food and fiber we grow.
Insects are directly involved with the pollination and reproduction of thousands of species of plants. Insects act as disease vectors of thousands of species of plants and animals. Insects are consumed by thousands of species of other animals as well as insects.
Insects cannot help but play a major role in the evolution of terrestrial life on this planet.
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