Planet of the Bugs, Evolution and the Rise of Insects

Message 1 of 3 (783510) 05-05-2016 8:03 PM

Shaw gives a synopsis of the history of life and discusses the geological timescale and strata associated with different ages and the fossil organisms found therein.

The emergence of the Arthropods early in the Cambrian and the explosion of their incredible species diversity continues right up until today. He compares the Arthropods and other Invertebrates with Vertebrates and notes that the latter have always been superseded by the Arthropods as far as species numbers and diversity. Our backboned ancestors moved out of the oceans many millions of years after the Arthropods. We have marked the ages in the rocks with a vertebrate-centric bias; The Age of Fishes, the Age of Amphibians, and so on as if their appearance in the fossil record are major events, when actually far more significant events were occurring in the evolution of the Invertebrates in the oceans and on land. Once the Insects appeared they rapidly became a major selective force in the rest of the non-marine biosphere.

I have read many books on the history of life over the years, but I have to say this is one of the best, so far.

Message 2 of 3 (783529) 05-05-2016 10:32 PM

Reply to: Message 1 by Tanypteryx 05-05-2016 8:03 PM

A quick look at the Amazon page for his book reveals it to be a fascinating piece of work, so I'll definitely add this to my books-I-have-to-have-in-my-personal-library list. Thanks for sharing.

Edited by Genomicus, : No reason given.

Message 3 of 3 (783531) 05-05-2016 11:14 PM

Reply to: Message 2 by Genomicus 05-05-2016 10:32 PM

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.