Microfossils are important to paleontology in a number of ways. They facilitate in dating other fossils, help put together a portrait of an ancient environment, and even have importance in the oil and mining industries. And since they are usually found in huge clusters within sedimentary rocks, microfossils are by far the most abundant of biological, fossilized remains.
What are Microfossils?
In general, microfossils are the miniscule remains of protists, fungi, bacteria, plants, and animals. This seems like a very diverse grouping, and it really is. Microfossils are not grouped together according to their relationships to one another, but are categorized as such only because of their tiny size. They are generally no larger than four millimeters.
For instance, not only are traditionally small and sometimes microscopic life forms considered in this subsection of paleontology, but so are tiny bones of the larger creatures. This makes for a very assorted field of study, but it remains since its first recognition as a field in 1883 as a very significant one.
Types of Microfossils
Protists and prokaryotes (organisms lacking cell nuclei, among other things) are the oldest, and the most multitudinous of the microfossil subgroup. Protists and prokaryotes, mostly single-celled remains, were the only living organisms on Earth for most of life’s history, so their numbers are understandable. These organisms greatly assist in the studies of early evolution.
Ostracods, shrimp-like crustaceans, are the most advanced forms of full-organism microfossils studied. They are bean shaped, and their shells are calcitic, so they fossilize well. When one of these crustaceans dies, their bodies decompose, leaving their calcium-rich shells behind.
The rest of the field of study is comprised of small fossilized remains of animals, plants, and various types of fungi. The fossilized fungi are often found within larger plant fossils, but are generally abundant and often ignored by paleontologists because of their relationship with plants. As for animals, all creatures with bones or calcium-rich skeletons have heartily contributed to the study of microfossils.
How are Microfossils Useful?
The most immediately significant use of microfossils is their ability to assist in age-dating the rocks in which they are found. And since they are so abundant - found in many types of sedimentary rocks – they are particularly useful.
Not only can they date their fossilized environment, but microfossils can also tell paleontologists a great deal about the types of environments in which they once lived. For instance, most of the single-celled microfossils found once lived in water, and their fossils can be great indicators of water depth. Some types of ostracods, which are often marine creatures, can give some hints of salinity.
Microfossils have played a big part in the current climate change studies as scientists struggle to record ancient temperatures in order to compare. Once again because of their abundance, they offer a good indicator of climate change over a specified period of time, depending on the fossils collected.
As immediately interesting as dinosaurs, giant prehistoric birds, terrifying monster sharks, and other prehistoric fossils can be, it is really the small packages that have really made waves in paleontology.
Microfossil research promises to continue to tell us more than we ever dreamed we could know about Earth’s history. For an extensive listing of microfossils, be sure to visit UC Berkley’s helpful catalog.
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