So far in our educational posts we’ve looked at what fossils are and how they form. But not all fossils are bones, shells, or teeth - some of the most interesting ones are trace fossils.
A trace fossil isn’t the creature itself, but the marks it left behind. Think of them as the footprints, doodles, or even toilet breaks of ancient life, preserved in stone. They give us behavior, not just anatomy.
Here are some of the main types:
Footprints – from single steps to whole track ways, showing how dinosaurs walked, ran, and sometimes moved in groups.
Trails - Like footprints, but typically from smaller critters, like trilobites, crawling and scurrying around through soft muds and other sediment.
Burrows – tunnels dug by worms, crustaceans, and other critters digging down through ancient sea floors. These tunnels then fill in with sediment which hardens to preserve the structure.
Feeding marks – scratches, bite marks, etc, left on shells and bones, which help us understand the diets and feeding habits of ancient animals.
Coprolite – yup, fossil poop. Surprisingly useful for figuring out diets!
Trace fossils are a big deal because they give us insights bones can’t. A skeleton can tell us what an animal looked like, but a footprint can tell us how fast it ran, how it carried its weight, and sometimes even how it interacted with others.
Isn't it funny that sometimes, the most ordinary things an animal did millions of years ago can be the most extraordinary to us today.
Fun fact: Melanosomes, which are microscopic pigment 'traces' preserved in fossils, can classed as a type of trace fossil. By comparing their shapes to those in modern animals, scientists and paleontologists can actually make educated predictions about the colours of extinct creatures. It's how we can be pretty confident that dinosaurs had colourful feather plumage, and so likely evolved wings as a way of attraction, and accidentally discovered a way to fly!
