Small Fossil Insects Hold Big Clues To The Prehistoric Past

This article was published in advance of DinoFest 2026, which happens at NHMU January 31 and February 1. Prebook your tickets and sign up for exclusive workshops today!

By Olivia Barney 

When you think of paleontology, what comes to mind? Do you think of dinosaur fossils and Ice Age animals? These are popular topics of interest for paleontologists, but they’re far from the only fields of study. Paleoentomology, for example, looks at the fossil record of insects — an important area of study that helps trace the evolution of insects across time. 

Fossil insects look different from the fossils of animals with hard parts. Unlike dinosaurs and their prehistoric relatives, insects lack the teeth and bones that are preserved into fossilized rocks. But in the right set of conditions, their delicate bug bodies can be preserved. 

Fossil Insects Hold Clues to the Past 

Fossilized beetle preserved in tar from the La Brea Tar Pits Jack Rodgers

There are two main ways insects are preserved in the fossil record. The first is through the preservation of the actual insect. Occasionally, like with Ice Age beetle specimens from the La Brea Tar Pits, the insect body is extremely well preserved in three dimensions (as if they’ve simply been frozen within a moment in time). More often, however, insects are flattened into the sediment they’re preserved in, appearing two dimensional (the way a mosquito might look after you’ve squashed it). These flattened insects might seem unremarkable to a casual observer, but to researchers, they’re an important record of the bugs that lived thousands, and even millions, of years ago, with anatomical details finely preserved. 

Petrified wood shows evidence of insect burrowing. Jack Rodgers

The other way an insect can be preserved is through trace fossils. Trace fossils don’t preserve the insect body itself, but rather the evidence of an insect’s presence. For example, a piece of petrified wood might show evidence of burrowing, tracks across mudflats record an insect's movement, and leaves can display evidence of being eaten. These kinds of fossil records can’t tell us exactly what species left the evidence behind, but they can help us narrow down the general group that the insect belonged to. This helps us map out how different groups of insects interacted with their environment and evolved over time. 

You can see both types of insect fossils for yourself during DinoFest at NHMU. During the annual, two-day festival, the Museum’s paleontology collections will be open to the public, and you’ll have the chance to look at real Museum specimens — including fossil insects. As part of the weekend’s events, NHMU will welcome expert paleontologists from around the world for a series of mini lectures and Q&A sessions. One of these speakers, Dr. John Foster, will be presenting on fossil insects from the Jurassic Period (the time of Allosaurus and Diplodocus). His talk will be fascinating because many of the bugs we know today hadn’t yet evolved during the time of Jurassic-aged dinosaurs. 

What Insects Lived With the Dinosaurs? 

During the Jurassic Period, there were no flowering plants; they hadn’t yet evolved. And because the environment featured different plants, it also featured a different mix of insects than what we’re used to seeing in our neighborhoods. During the age of the Allosaurus, you could find a wide variety of beetles, flies, and dragonflies, but you couldn’t find insects like ants, bees, or termites because they hadn’t evolved yet. 

As flowering plants began to appear, new insects (particularly those we refer to as pollinators) started to evolve. Flowering plants provided the ecosystem with new resources, including food and shelter, that allowed different types of bugs to thrive. Dr. Randy Irmis, NHMU’s Curator of Paleontology, described how these new plants allowed organisms to specialize. “You have insects that specialize on feeding on the flowers and their nectar, but then you have carnivorous insects, predatory insects, that specialize on eating those insects that feed on the flowers.” 

Flowering plants first appeared during the Early Cretaceous Period, and for the next 10-20 million years, plant and insect life flourished. New groups of arthropods (the larger group that insects belong to) emerged, and those groups continued to diversify. By the Eocene Period, about 50 million years ago, most of the major groups of insects we know of today are around. 

Buzz on in to This Year’s DinoFest 

As we take flight into 2026’s DinoFest activities, which focus on the hunters large and small that dominated prehistoric skies, don’t forget to examine the winged insects that lived among the dinosaurs. DinoFest: Prehistoric Skies takes place on Saturday, January 31, and Sunday, February 1. You can get a behind-the-scenes look at collections from 10:00am to 4:30 p.m. each day and learn more about fossil insects from Dr. Foster during his Sunday afternoon DinoBite lecture. 

DinoFest is our biggest, most popular event of the year, so we highly recommend prebooking your tickets now to avoid day-of admission lines at the festival. To level up your DinoFest experience even further, consider registering for one of our fun DinoFest Workshops. These workshops are brand new this year, offering you the chance to create claw casts, watercolor landscapes, fossil feathers, or glow-in-the-dark constellations. Since workshop fees include festival admission, which is free for Museum Members and Copper Club, all Members will save 20 percent on workshop registrations. You can also subscribe to one of our email lists to be entered to win an iconic Smilodon skull cast, which will be given away during Sunday’s DinoFest event.