Being that this is the first official post about bugs, what better way to begin than with the history of insects. Now, I don’t tend to be very long winded when it comes to writing (unless it is my own research) and plus I think there is a greater potential to lose readers when posts go on for days. So I intend to keep posts brief and hopefully provide sources and links to other places so that you can seek out further detail if you are interested.

Most general entomology text books don’t actually touch on paleoentomology, and probably for a good reason–because the presence of insects in the fossil record is not all that great. And we are only recently developing DNA/Genetic code banks for insects and using cladistics to understand the evolutionary relationships that insects have with one another.

There is fossil evidence that suggests that insects first appeared during the Devonian period (some 400 million years ago) and that the first insects resembled our modern day springtails (see here ). I don’t know about you, but for me, it is a really hard thing to fathom the idea of 400 million years ago. Scientists think that plant communities increased during the Late Devonian, which helped prompt different insect trophic (feeding) levels. Since there were so many plants, the first insects were probably plant and detritus feeders. It is not until the end of the Early Carboniferous period that winged insects are found in the fossil record, and the issue of insect flight is still a matter of debate (whether flight is an ancestral or derived trait and what brought about the development of wings for flight). The Triassic period (where all the continents reunited to form Pangea) is thought to be the time where the greatest amount of insect evolution took place. There are several scientists who have made careers out of trying to map out the evolution of insects. One of the most common referenced fossil insects is probably a giant dragonfly (wingspans around 30 inches) that is estimated to be 155 million years old. Why are insects not that big anymore (some of you are probably saying ‘thank God they are not’)? Entomologists think that is has to do with the changes in the atmosphere (mainly oxygen), but that has also been contested. I honestly haven’t done a whole lot of reading into this area, so if you know more info, do chime in. For another little blurb on insects and dinosaurs, see this piece that NOVA has online here.

Insects are broken down into three main groups: bristletails, silverfish, and winged insects. I’ll probably only ever really talk about the winged insects in this blog. The winged insects are broken down further into 3 more groups: (a) the mayflies, (b) the dragonflies and damselflies, and finally (c) everything else, which would be your beetles, flies, butterflies/moths, wasps, bees, etc. What’s funny is that even though this group is the ‘winged insects’, not all of the insects actually fly (i.e., some species of cockroaches, termites, ants, etc) and this is part of the reason why there is still a debate about the evolution of insect flight.

Now some of you may be at the point of wondering what the heck insects are even good for. Trust me, they are good for more than just squashing :). Actually, insects have been intertwined with human culture for a very long time. Here are a couple examples of insects across culture:

1. The Egyptians believed the scarab beetle (dung beetle) was sacred, and we often see them carved into tombs and other ancient artifacts.
2. In ancient Mexico, butterflies, crickets, and fleas were studied by the Aztecs and Mayans. They looked to insects for explanations of life and death.
3. Insects play a role in many different religions, in fact, many insects are mentioned in the Bible and most often symbolize destruction (i.e., maggots, flies, lice, locusts). For more on what role beetles have played in religion, see here.

The relationship of insects and humans is not only symbolic. Many different cultures, even in the present, use insects for a food source. There is actually a whole field dedicated to the study of insects as human food (entomophagy). It’s true what they say, insects are high in protein (as well as calcium, magnesium, iron, and riboflavin). Most of us westerners are repulsed by the thought of eating a bug, but our reasons are not based on any scientific/rational basis. We are raised in a culture that has taught us to fear insects and equate them with a dirty/filthy environment. This is not to say that I opportunistically pop insects in my mouth all day long. I will be the first to admit that while I am enthusiastic about insects, I will stick to the graham cracker cut-outs until I am desperate for a little protein and/or sign up to be on Survivor.

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